Measuring impacts of land development an initial approach

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MEASURING
IMPACTS OF

LAND DEVELOPMEMT
An Initial Approach

Philip S. Schaenman
Thomas Muller

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169.7 <
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THE-URBAN INSTITUTE
1974

PROPERTY OF THE
UNITED STATES GOVERMENT
NATIONAL OCEANIC AND
ATMOSPHERIC ADIMINISTRATION

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MEASURING
IMPACTS OF
LAND
DEVELOPMENT

An Initial Approach

Philip S."Schaenman
Thomas Muller

DEPARTMENT OF COMMERCE NOAA
COASTAL SERVICES CENTER
2234 SOUTH HOBSON AVENUE
CHARLESTON , SC 29405-2413

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of the U.S. Department of Housing and Urban Development under the
provisions of Section 701(b) of the Housing Act of 1954, as amended,
to The Urban Institute. The fiindings and conclusions presented in this
report do not represent official policy of the Department of Housing
and Urban Development or The Urban Institute.

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FOREWORD

In many communities, poor land use decisions have given development and urban growth a
bad name and a bad press. They have saddled many communities with unfortunate conditions
which may take years to correct, if they can be corrected at all. It is not enough to decry the situ-
ation. A large body of opinion in both the private and the public sectors already agrees that
"something should be done." Within the varied and, in many cases, restrictive legal, economic,
and political framework in which land use policy must operate, there is an urgent need to devise
better tools that can help local governments and others involved in the development process
arrive at better land use decisions.
This report represents the early stages of one such tool or mechanism-a system for assessing
the effects of land development proposals. No pretense is made that this system is yet a finished
product, nor is it intended to encompass all the elements of sound land use planning and manage-
ment. It is a rough beginning in one critical area. Its publication at this stage is intended to encour-
age elected officials, planners, developers, researchers and concerned citizens who are involved in
land use matters to test at least parts of the system and to join in its further refinement.
The systerft presented here involves a comprehensive set of impact measures, and in the end
still requires judgments of the findings. Unfortunately, there is no single litmus test or magic for-
mula that yields a yes or no answer for all land use proposals. It is in the nature of land develop-
ments that almost every aspect of community life may be affected. One cannot assure sound land
policy without considering the health of local business, employment opportunities, housing supply,
local government services, transportation, crime, clean air and water, and all the other matters
embraced in the set of impact measures. And even with the best impact estimates, officials must
still weigh the likely outcomes of development in light of community goals. In the continuing work
on this project, suggestions will be welcomed for ways to improve each aspect of the system to
assure that the data collection techniques and analytic approaches for each measure are concise, to
the point, reliable, economical, and practical for lo, cal governments.
An advisory group of elected officials, government planners, representatives of citizen's asso-
ciations, and technical experts is helping to guide the overall work of,this project. In addition,
officials at the Department of Housing and Urban Development have contributed ideas to the proj-
ect, and local government personnel are assisting generously in the continuing work on impact
measures.
The Land Use Center was established by The Urban Institute in 1973 to focus on research,
education, and technical assistance to various levels of government in the areas of land use and ur-
ban growth. The Center, under the direction of Worth Bateman, has several other studies under
way describing the state of the art in impact measurement and analyzing the experience of
selected state and local governments with it. These and other reports-concerned with land use
governance, taxation, citizen participation, and regulatory policy-will be issued as the research
is completed.

Washington, D.C. WILLIAM GORHAM, President
November, 1974 The Urban Institute

ift

CONTENTS

Page

Foreword . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii

Acknowledgments ................................................. vii

Advisory Group . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ix

SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . I

Use of Impact Measures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Data Collection and Presentation ..................................... 2
General Issues for Land Use Decision Making .............................. 3

INTRODUCTION .................................................. 5

Current Evaluation Shortcomings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Audience for this Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Managing a Large Set of Measures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Terms and Emphases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Are We Jumping the Gun? . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Organization of the Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

PART 1. DEVELOPING AND USING A SET OF IMPACT MEASURES

1. SUGGESTED IMPACT MEASURES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Starting Point-Community Objectives .................................. 13
Measures to Match Objectives ....................................... 13
Selecting Measures for Evaluating Particular Developments ... ................. 14
Type of development ......................................... 14
Local conditions and priorities ................................... 14
What is being displaced? ....................................... 16
Interrelationships and tradeoffs ................. ................. 16
Costs .................................................. 16
Maintaining Public Services: Capacity Measures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Il. HOW IMPACT MEASURES CAN ASSIST LOCAL DECISION MAKERS . . . . . . . . . . . . . . 19

Evaluating Proposed Developments .................................... 19
Complementary to existing codes ............................... ... 19
What developments to analyze ................................... 19
Range of development options to consider . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Initial screening . . . . . . . . . . I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
When quantification is weak . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Weighing the measurement results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Clientele groups and spillovers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Who should undertake evaluations? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Evaluating Past Developments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Evaluating Comprehensive and Neighborhood Plans .............................. 22

Page

III. PUTTING THE MEASURES IN PERSPECTIVE ............................ 25

Relating Impacts to the Community and Region at Large ....................... 25
Collective effects of development .................................. 25
Spillover effects ............................................ 26
Secondary impacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Institutional, Procedural, and Political Issues . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Precedents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Political problems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Information overload and aura of precision . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Delays and costs in decision making . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

IV. CLIENTELE GROUPS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

Groupings by: Physical Proximity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Business Relationships . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Political Jurisdictions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Socioeconomic and Demographic Characteristics . . . . . . . . . . . . . . . . . . . 32
Other Interest Groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
The Long-Term Public Interest . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

V. DATA PRESENTATION FORMATS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Impact Measurement Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Public Facility Capacity Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

PART 2. IMPACT MEASURES-ANALYSIS AND DATA COLLECTION APPROACHES
(for detailed contents of Part 2, see pages 41-42.)

1. Economy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
11. Natural Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Ill. Aesthetics and Cultural Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
IV. Public and Private Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
V. Housing and Social Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

Appendix: Other Impact Measures Considered . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

EXHIBITS

I . Measures for Evaluating the Impacts of Land Development . . . . . . . . . . . . . . . . . . . . 10-11
2. Community Objectives for Regulating Land Development . . . . . . . . . . . . . . . . . . . . . . . 15
3. Clientele Groups Potentially Affected by Development . . . . . . . . . . . . . . . . . . . . . . . . . 30
4. Illustrative Display of Impact Measure Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
5. Capacity of Public Facilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
6. A Format for Pr 'esenting the Effect of Development on Risks from Natural Disasters . . . . . . . . 67
7. Other Impact Measures Considered . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

ACKNOWLEDGMENTS

The research supporting this work was sponsored by the Office of Policy Develop-
ment and Research of the U.S. Department of Housing and Urban Development. The
suggestions and encouragement of Wyndham Clarke, Director, Division of Community
Planning, Development, and Conservation, and his deputy, James Hoben, have been
greatly appreciated.
James Kalish and David Talbott, as consultants to The Urban Institute, and Dale
Keyes, Kathy Christensen, and Grace Dawson of the Institute staff made important con-
tributions to this report. Additional research assistance was provided by Nancy Tuck,
Kathleen Hudak, and Peter Nelson. Walter Rybeck of The Urban Institute edited the
overall report and contributed substantively to the content.
The study was initiated under the direction of Harry P. Hatry, Director of the State
and Local Government Project of The Urban Institute. A second phase to further develop
the proposed procedures is being continued under Worth Bateman, Director of The Urban
Institute's Land Use Center.
The authors are grateful to Donald Fisk, Louis Blair, Michael Flax, John Hall,
Damian Kulash, Frank deLeeuw, Henry Peskin, and Ralph Smith, all of The Urban Insti-
tute, for their useful critiques, and to Judy Fair and other members of the Institute's
library staff for their help in support of the research.
Special thanks are also given to many individuals who critiqued an early working
draft of this study and provided many valuable suggestions: Thomas Ragonetti, Cornell
University; Jeffrey Luke, Planning Department, Scottsdale, Arizona; Professor Joseph Heikoff,
State University of New York, Albany; Professor Rae Zimmerman, New York University;
Norman Emerson, Office of the Mayor, and Nancy Minter and Hethie Parmesono, City
Planning Department, Los Angeles, California; Sanford Getreu, former Planning Director,
San Jose, California; Albert Gollin, Bureau of Social Science Research, Washington, D.C.;
Robert Witherspoon and Sumner Myers, Institute of Public Administration; and Allen
Schectel and Janice Levin, State Regional Planning Department, New Jersey.
The authors, of course, assume full responsibility for the present report.

P.S.S.
T.M.

Vil

ADVISORY GROUP

The Advisory Group is assisting in the continuing efforts to improve the system described in this report for
measuring the impacts of land development. As persons involved in the development process, they are
providing a users' perspective to the work-that is, helping to assure that the suggested measurement
procedures are practical and useful. This initial report, however, is the sole responsibility of the authors at
The Urban Institute.

TIMOTHY A. BARROW / Mayor, Phoenix, Arizona ROBERT H. PASLAY / Planning Director, Planning Commission,
Nashville, Tennessee
KURT W. BAUER / Executive Director, Southeast Wisconsin
Regional Planning Commission, Waukesha, Wisconsin RICHARD A. PERSICO / Executive Director, Adirondack Park
Agency, Ray Brook, New York
FRANK H. DEAL / Deputy Director for Research, American
Society of Planning Officials, Chicago, Illinois JAMES R. REID / Director, Office of Comprehensive Planning,
Fairfax County, Virginia
MELVIN L. BERGHEIM / Councilman, Alexandria, Virginia
E. JACK SCHOOP / Chief Planner, California Coastal Zone Conser-
JOSEPH F. CATANIA / Chairman, Board of Commissioners, Bucks vation Commission, San Francisco, California
County, Doylestown, Pennsylvania
DUANE L. SEARLES / Special Counsel on Growth and Environ-
RICHARD F. COUNTS / Zoning Administrator, Planning ment, National Association of Home Builders, Washington, D.C.
Department, Phoenix, Arizona
PHILIP A. STEDFAST / Planning Director, Department of City
CARL D. GOSLINE / Director of General Planning, East Central Planning, Norfolk, Virginia
Florida Regional Planning Council, Winter Park, Florida
DAVID L. TALBOTT / Director of Planning, Falls Church, Virginia
BERNARD D. GROSS / Glover Park Citizens Association, and
New Communities Program, HUD, Washington, D.C. RICHARD E. TUSTIAN / Director of Planning, Maryland National
Capital Parks and Planning Commission, Silver Spring; Maryland
HARRY P. HATRY / Director, State and Local Government
Research Program, The Urban Institute, Washington, D.C. F. ROSS VOGELGESANG / Director, Division of Planning and
Zoning, Indianapolis, Indiana
TED KOLDERIE / Executive Director, Otizens League, Min- THORNTON K. WARE / Planning Director, Rensselaer County,
neapolis, Minnesota Troy, New York
JACK LINVILLE, JR. / Assistant Executive Director, American In- JOSEPH S. WHOLEY / Chairman, Arlington County Board, Arling-
stitute of Planners, Washington, D.C. ton, Virginia, and Director, P@ogram Evaluation Studies, The Ur-
ban Institute, Washington, D.C.
ALAN H. MAGAZINE / Supervisor, Fairfax County Board, Fairfax,
Virginia, and Project Director, Contract Research Center, Inter- FRANKLIN C. WOOD / Executive Director, Bucks County Planning
national City Management Association, Washington, D.C. Commission, Doylestown, Pennsylvania

SUMMARY

Local governments today face no more pressing issues than those surrounding land
developments and rezonings within their jurisdictions. Is growth overruning the capacity
of local facilities? Will new development pay its way or be a drain on present taxpayers?
Intentionally or otherwise, are somesegments of the population excluded from the bene-
fits of new growth or made to bear disproportionate burdens of growth? For environ-
mental or other reasons, should development be limited? Are local housing and employ-
ment needs being met?
The questions run on and on-and most of them are as tough to answer as they are
important.
Elected local officials and planning commissions responsible for guiding or accomo-
dating to urban change try to grapple with such questions but are severely handicapped by
their limited time, staff, and money. Officials usually have to estimate the impacts of
each development on an ad hoc basis, one at a time. The resultant evaluations often are
not systematic or comprehensive. Estimates of intermediate outcomes are sometimes not
translated into the likely end results for particular citizen groups and for the community
as a whole. The evaluation dialogue among officials, developers, and citizens may raise
vital concems-"urban sprawl," "character of the neighborhood," "pollution," and so
forth-but typically these are not adequately defined.
This report summarizes an initial attempt to outline an approach intended to help alle-
viate some of these problems. It sets forth measures and procedures for assessing the impact
of land developments on economic, environmental, aesthetic, public and private service,
housing, and social concerns. These measures and procedures are intended primarily to
assist local decision makers and their staffs in confronting land use decisions in a more
systematic way and with an emphasis on how citizens are affected. They also speak to the
interests of concerned citizens and citizen groups by portraying potential impacts in a more
understandable and open fashion.
The report concentrates on ways to develop comprehensive data on the expected im-
pacts of development. This is viewed as only one of the vital elements in land use decision
making. Other aspects, recognized as exceedingly important but only briefly mentioned
here, include the overall planning process, administrative mechanisms needed to implement
the use of impact measures, and the ways that communities- through the political system,
citizen involvement, and the like-make the ultimate tradeoffs between alternative land
use proposals.
Further development of the measures and data collection procedures are currently
under way in cooperation with two local governments, and with the help of an advisory
group of planners and elected officials from a wide variety of jurisdictions. Readers of
this publication may participate in this effort to advance the state of the art of impact
evaluation methods by considering this report a trial proposal to which their responses
-queries, arguments, examples, and clarifications-will be most appreciated.
The use of impact measures will help clarify the likely advantages and disadvantages
of a development, enabling officials and administrators to act more confidently to accept
a proposal, to negotiate maximal positive aspects, to identify problems that require local
policy changes, and to reject proposals when projections appear detrimental. In short, they
should help communities better manage the course of future growth.
Some of the tentative recommendations emerging from the study to date follow.

USE OF IMPACT MEASURES

1. Local officials in each community should weigh each new development-
residential, commercial, industrial, and public-against a check list of major considerations
or impact measures. Each community should develop its own check list based on local
objectives. The measures should emphasize end impacts on citizens whenever possible.
A suggested comprehensive list of impact measures that could be used as a starting point
for various types of developments, and for evaluating existing as well as proposed
developments is presented in Exhibit 1. The larger the development or the greater its
potential impact, the more carefully each aspect of the check list needs to be considered.
For most developments only a few measures are likely to be of sufficient importance to
warrant detailed data collection. Systematic use of the check list approach for each devel-
opment should help improve the consistency and comprehensiveness of evaluations, even
if some of the measures can only be estimated crudely.
2. Local officials can use most of the same list of measures for evaluating groups
of developments and alternative comprehensive or sector plans. Some measures are actually
easier and likely to be more meaningful to consider for groups of developments or for
overall growth than for individual small developments. This is especially so for the eco-
nomic and some of the natural environment impacts.
3. Land use impacts on specific clientele groups should be considered in addition
to those for the community as a whole. Various segments of the population, such as busi-
nessmen, residents of the neighborhood being redeveloped, or low-income families may be
affected in quite different ways by the proposal. Some may be helped, some may be hurt,
and others not affected significantly. Among the clientele groups to consider are those
given in Exhibit 3.
4. ne impact of selected past developments should be evaluated regularly. These
evaluations will test the.accuracy of impacts that were estimated-be fore those develop-
ments occurred-by both the local government and by the developer. The accumulated
case histories will serve as a basis for improving future impact assessments for various types
of developments. They may also aid in holding developers to their commitments.

DATA COLLECTION AND PRESENTATION

5. Data collection procedures relating to each measure on the check list should be
specified and used consistently. Part 2 of this report, while recognizing that the state of
the art for many measures is rudimentary, offers a tentative description of such procedures.
Some give fairly reliable results. At the other extreme are procedures still in the pretest-
ing stage whose feasibility and practicality are uncertain.
6. Procedures of different levels of detail should be developed for each measure to
correspond to needs for both quick reviews and careful analyses. Clearly, all develop-
ments cannot be evaluated in the same detail when large numbers of proposals are being
presented to public bodies for decisions.
7. The degree of uncertainty,for each estimated impact should be explicitly stated.
For many land use decisions, highly precise estimates are not needed. However, the con-
fidence in the estimate should be brought to the attention- of policy makers and the public.
In some instances it will be useful to give the range of possible impacts in addition to the
"best" or "most likely" estimates.
8. Impact measures should be displayed for decision makers in a readily understand-
able, nontechnical format. Highlights should be presented in a few charts that summarize

2 Measuring Impacts of Land Development

impacts on various clientele groups and show the cumulative effects on groups of proposed
developments. The degree to which the development fits in with the hierarchy of plans for
the area, both in general and with respect to specifics, should also be indicated. Merely pre-
senting vast quantities of technical data is not likely to improve decision making; the findings
need to be distilled and translated.

GENERAL ISSUES FOR LAND USE DECISION MAKING

9. The collective impact of communitywide development activity should be con-
sidered in assessing any individual development. The cumulative effects of all currently
planned land use changes that have a reasonable chance of taking place-and not merely
the isolated effects of each single development, which may appear quite insignificant-should
be considered. The legal mechanisms surrounding land use decisions, however, are geared to
separate actions on single developments rather than to policies affecting series and sets of
proposals, so it will not be easy to maintain or act on the cumulative perspective.
10. Spillover effects- the impact of land use decisions on neighboring jurisdictions-
should be evaluated. The political realities in areas where activities of adjacent communi-
ties are uncoordinated and highly competitive may make this goal difficult to achieve. If
sheer altruism and concern for the larger public good will not generate action in this direc-
tion, perhaps self-interest will-that is, showing concern for neighbors may be a means of
persuading them to reciprocate and give attention to spillover effects from their decisions.
Because many localities have been indifferent to regional impacts, a movement is already
underway to shift land use authority to regional and state governments; this movement is
bound to gain momentum to the extent local governments continue to abdicate responsi-
bility in this matter.
11. Precedents requi .re sped.al attention. Even when the immediate impact of a land
use decision may be small, its long-term effects may be magnified if it involves new legal
or policy directions. For example, allowing a small development in a previously protected
woodland may' have little immediate environmental, aesthetic, or recreational impact, but
the pattern of enc'roachment could set off a chain of development with major effects..
12. Alternative land uses and alternative sites-and not only those being proposed at
a particular time-should be considered in the evaluation. A community has a wide range
of needs which may include low-income housing, moderate-income housing, employment,
shopping, open space, and public facilities. Evaluations must consider the impacts of al-
ternative ways that these needs may be met if the proposed development is not approved.
Although the proposed development may have some negative impacts, they may not be as
bad as some of the alternatives. Further development or deterioration of the site that may
take place without any approval by the local government also should be considered, and
not just the conditions that currently exist on the proposed development site.
13. The checklist approach of impact measures is not offered as a substitute for
comprehensive analysis and reform of land use practices. The approach described here is
presented as a practical aid for local officials who do not have the luxury of waiting years
or decades for ultimate, ideal solutions in deciding the development issues on their daily
agendas, but who must decide on land use proposals one at a time. A growing number of
observers believe that fundamental changes in land use theories, strategies, and policies
are needed, based on detailed analyses of the operation of the real estate market, the
influence of government programs and taxes on development patterns, and the labyrinth
of present land use controls. Use of the measures in this report, while not aimed at that
level of policy reconstruction, nevertheless may contribute to it by focusing public atten-
tion on issues in ways that suggest corrective actions.

Surnmary 3

INTRODUCTION

With local governments and the general public increasingly concerned about changes
in land use, and especially those involving higher intensity of use, the inadequacy of pres-
ent tools for evaluating the impact of such changes has become apparent. A number of
guidelines have evolved over the years- comprehensive plans, zoning ordinances, building codes,
housing codes, subdivision regulations, and, more recently, state and federal requirements
for environmental impact evaluations. These all have their strengths and uses, but they
do not add up to a system that is sufficiently comprehensive in scope and specific in detail
for gauging the effects of new developments. Officials and citizens alike are distressed at
the mass of data but lack of useful information available to decision making.
It has become evident that improved techniques are needed for estimating the spe-
cific impacts of development on a community's economy, natural environment, public
and private services, appearance, housing, and social conditions. This report suggests a set
of measures and procedures that local governments may use for this purpose. It also of-
fers a framework and a methodology for a community to arrive at its own set of evalua-
tion criteria.
The report focuses primarily on ways to improve the evaluation of individual pro-
posed d evelopments- which, like it or not, is the most prevalent type of land use decision
facing local and regional government officials. Many of the suggested measures also apply to
evaluating cumulative effects of groups of proposed developments, and to evaluating alter-
native growth plans. For some measures, effects of individual developments are likely to
be insignificant if viewed in isolation from other developments.
The same measures also may be applied to existing developments. Retrospective
evaluations, although rarely undertaken by localities today, are strongly recommended for
several reasons. They may identify consequences of earlier land use decisions that were
not foreseen at all or that were incorrectly estimated at the time they were made, and
thus throw light on how to make more reliable projections under similar situations in the
future. Studies of past developments also may identify conditions that require corrective
action by the developer or community.
This report does not deal more than incidentally with the way comprehensive planning
determines and updates a hierarchy of local plans against which development should be
evaluated. There is little discussion here about administrative mechanisms for implementing
the impact-measures set forth. And the report does not dwell in detail on how value judg-
ments and tradeoffs about land uses are reached through the political process or meetings
between officials, citizens, and developers. The importance of all these matters is recognized
and they are being considered in the continuation of this study.

CURRENT EVALUATION SHORTCOMINGS
Planners and others have called attention to many limitations and inadequacies of
current efforts to evaluate proposed development. To note some ofthese briefly under-
scores the necessity for a new approach and indicates the kinds of gaps which must be
bridged. Current evaluations are often characterized by the following features:
0 A systematic, comprehensive approach toward identifying relevant criteria is
often missing. Important social and economic considerations are often -omit-
ted altogether from the evaluation.

0 There tends to be too much concern with technical criteria whose relationship
to citizen or community well-being is unclear. Examp .les include floor area ratios

(FAR's), building setbacks, and persons per acre. One commentator on this sit-
uation has written that it is often assumed there is a series of links between con-
trols and certain community goals when no such chain exists.' For instance,,
more restrictive FAR's will not necessarily reduce traffic congestion or a sense
of crowding, nor assure privacy.

� The evaluation dialogue among planning officials, developers, and citizens is
filled with generalities and with terms that are not well-defined, such as "urban
sprawl," "character of the neighborhood," and "neighborhood stability."

� The evaluation criteria actually being used by the decision makers often are not
openly stated and discussed. This may result from an attempt to avoid contro-
versy, or simply because they have not had the time or staff to develop and
document such criteria.

The measures and procedures offered in this report are intended to help alleviate the
shortcomings just cited by providing a way to describe impacts on the citizens more ex-
plicitly, systematically, comprehensively, and in reasonably nontechnical terms. Any set
of practical measures, however, is obviously unlikely to be satisfactory on all these scores.
Nevertheless, there seems to be enough room for improvement within the resource limits of
most governments to warrant the effort.

AUDIENCE FOR THIS REPORT

The proposed measures and data collection methodology were devised primarily for
municipal and county officials and their staffs who are involved in land use matters. It
seems likely, however, that much the same approach would be useful to regional planning
commissions, councils of governments, and state governments.
The emphasis on making the measures and procedures understandable also should
give citizens more opportunity to participate constructively in land use matters.

MANAGING A LARGE SET OF MEASURES

When faced with a rather large list of impact measures- forty-eigh t in all, as set forth
in this report-local officials are likely to be concerned at first that this approach may be
unwieldy and too expensive. It need not be.
It should be readily apparent that for any particular development, many of the im-
pact measures will not apply. This is because the full list of measures is intended to apply
to many types of development- commercial and residential, urban and suburban, large
and small, existing and proposed. Measures that are not relevant to a particular develop-
ment clearly may be bypassed. For most evaluations, the weeding out process will quickly
lead to a relatively small subset of pertinent measures. Even among the latter, it is likely
that only a few measures will assume major importance.
The proposed measurement procedures would indeed be impractical unless selectivity
is exercised in both the choice of measures and the depth of analysis. In general, the
more comprehensive and detailed analyses will be reserved for large developments,
precedent-setting developments, and for sets of smaller developments whose cumulative
effects appear to be significant.
As will be seen.in the detailed discussion, two levels of data collection are discussed
for some measures-one level for a brief, rough cut at estimating impacts (obviously the

1. Jacob B. Ukeles, The Consequences of Municipal Zoning Washington, D.C., Urban Land Institute, 1964.

6 Measuring Impacts of Land Development

more economical approach), and a second level where the community interest requires
and justifies more thorough analysis. Most evaluations would use the simpler form, partly
because of time, skill, and money constraints, but also because incremental impacts from
individual developments are not likely to be substantial enough to justify voluminous data
gathering and analysis.

TERMS AND EMPHASES

Land development. As used in this report, land development refers to a significant
change in the kind or intensity of use of a site. This includes, but is not limited to, land
use changes that require rezoning.'
Scale. The scale of development to be evaluated may range from a single highrise
structure to the reshaping of a major portion of a community.
Private-public. This report is oriented to development initiated by the private sector,
although the measures presented here generally may be applied to the public sector as
well. In the latter case, additional measures would be needed to determine the needs for
constructing such facilities as hospitals and fire stations, and to more fully reflect their
likely impact on service quality.
Clientele groups. The suggested measures are intended to reflect the concerns of
citizens. All citizens, however, are not affected in the same way, or in the same degree,
by particular developments. Therefore, besides looking at impacts on the community as
a whole, it is advisable to estimate explicitly the impacts on different population segments.
Unless this is done, the most articulate and aggressive groups may wield disproportionate
influence to the detriment, of others who have an equally legitimate stake in the com-
munity's future.

ARE WE JUMPING THE GUN?

The authors recognize-and underscore the fact-that much of the work reported
here is tentative and exploratory. It reflects only the initial phase of an ongoing study under
HUD sponsorship to investigate ways to improve the methodology for evaluating land
development. One school of thought is to withhold such material from public view until
more definitive statements can be made.
.However, because of the great interest in the subject today, it was decided to publish
an initial report in the hope that the proposed measures and data collection procedures
might provide a useful starting point for individual governments and stimulate them to
improve their own evaluation methods. Second, it is believed that subjecting the work at
this point to widespread review will be one important way of testing and advancing this
approach in the shortest possible time.

ORGANIZATION OF THE REPORT

The suggested measures and how they are formulated are presented in Chapter I of
Part 1. Chapter 11 discusses the role of the measures-that is, how they may be used by
local decision makers. Chapter III focuses on key methodological issues that have not
been totally resolved but that should be kept in mind when applying the measures. Chap-
ter IV indicates how the measures may be used to consider explicitly the impact of

2. A more detailed definition of land development is given in the proposed "Model Land Development Code,"
American Law Institute, 1970, pp. 8-11. (Unlike our definition, it excludes changes that can be made vAthin exist-
ing zoning.)

Introduction 7

development on different population segments or clientele groups. Chapter V suggests
some ways of presenting or displaying the findings from the impact measures.
Part 2 deals with the more technical details of applying the proposed measures. It
discusses the rationale, limitations, and alternative forms for each measure and outlines
procedures for data collection in each instance.

8 Measuring Impacts of Land Development

PART 1: DEVELOPING AND
USINGASETOF
IMPACT
MEASURES

EXHIBIT I

MEASURES FOR EVALUATING THE IMPACTS OF LAND DEVELOPMENTS

Impact Area' Measure
1. Local Econom proves or lessens the overall
@y
Public Fiscal Balance I . Net change in government neighborhood attractive-
fiscal flow (revenues less ness, pleasantness, and
4
operating expenditures and uniqueness.
annualized capital expendi- Landmarks 16. Rarity and perceived impor-
tures). tance of cultural, historic,
or scientific landmarks to be
Employment 2. Number of new long-term lost or made inaccessible.
and short-term jobs pro-
vided. IV. Public and ftivateSerpices
3. Change in numbers and per- Drinking Water 17. Change in rate of water
cent employed, unem- shortage incidents.
ployed, and underem- 18. Change in indexes of drink-
ployed. ing water quality and safety.
Wealth 4. Change in land values. Hospital Care 19. Change in number of citi-
11. Natural Environment2 zens who are beyond x
minutes travel time from a
Air 5. Change in level of air hospital emergency room
pollutants and number of (using such time as the
people at risk or bothered community considers rea-
by air pollution. sonable).
Water 6. Change in level of water 20. Change in average number
pollutants, change in toler- of days of waiting time for
able types of use, and hospital admittance for elec-
number of persons affected, tive surgery.
for each body of water.
Crime Control 21. Change in rate of crimes in
Noise 7. Change in noise and vibra- existing community or new
tion levels, and number of development (or expert rat-
people bothered by exces- ing of change in hazard).
sive noise and vibration.
Greenery and 8. Amount and percent change 22. Change in percent of people
Open Space in greenery and open space. feeling a lack of security
Wildlife and 9. Number and types of endan- from crime.
Vegetation gered or rare species that Fire Protection 23. Change in fire incidence
will be threatened. rates.
10. Change in abundance and 24. Change in rating of fire
diversity of wildlife and spread and rescue hazards.
vegetation in the develop- S
ment and community. Recreation 25. Change in the number of
people within-or beyond-a
Scarce Resource 11. Change in frequency, dura- reasonable distance (x miles
Consumption tion, and magnitude of or y minutes) from recrea-
shortages of critically scarce tional facilities, by type of
resources., and the number facility.
of persons affected. 26. Change in usage as a percent
Natural Disasters 12. Change in number of people of capacity; waiting times;
and value of property en- number of people turned
dangered by flooding, earth- away; facility space per
quakes, landslides. mud- resident; and citizen percep-
slides. and other natural tions of crowdedness at
disasters. recreational facilities.
Ill. Aesthetics and Cultural YalueS3 27. Change in perceived pleas-
Views 13. Number of people whose antness of recreational ex-
views are blocked, degraded, perience. 8
or improved. Education 6 28. Change in number of stu-
Attractiveness 14. Visual attractiveness of the dents within x minutes walk
development as rated by or y minutes ride from
citizens and "experts." school, by type of school.
15. Percent of citizens who 29. Number and percent of
think the development im- students having to switch
10

schools or busing status are substandard, and change
(from walking to busing or in number and percent of
vice versa). people living in such units.
30. C hange in crowdedness 40. Change in number and per-
"breakpoints" (such as need cent of housing units by
for added shifts) or indi- type (price or rent range,
cators (such as student- zoning category, owner-
teacher ratios); student, occupied and rental, etc.)
teacher, and parent percep- relative to demand or to
tions of crowdedness and number of families in vari-
pleasantness of schooling. ous income classes in the
Local Transportation 7 31. Change in vehicular travel community.
times between selected ori- People Displaced 41. Number of residents. or
gins and destinations. workers. displaced by devel-
opment-and by whether
32. Change in duration and they are satisfied with
severity of congestion. having to move.
33. Change in likelihood of Population Mix 42. Change in the population
finding a satisfactory park- distribution by age, income,
ing space within x distance religion, racial or ethnic
from destination or resi- group, occupational class.,
dent. and household type.
34. Change in numbers and Crowdedness 43. Change in percent of people
percent of residents with who perceive their neighbor-
access to public transit with- hood as too crowded.8
in x feet of their residences;
and numbers and percent of Sociability- 44. Change in frequency of
employees who can get Friendliness visits to friends among peo-
within x distance of work ple in the existing neighbor-
location by public transit. hood, and frequency of
35. Change in the rate of traffic visits between people in the
accidents (or expert rating existing neighborhood and
of change in hazard pre- the new development.
sented). 45. Change in percent of people
36. Number and percent of perceiving the neighborhood
citizens perceiving a change as friendly. 8
in neighborhood traffic haz-
ard; and change in pedestri- Privacy 46. Number and percent of
an usage of streets, side- people with change in "visu-
walks 18 and other outdoor al" or "auditory" privacy.
space.
47. Number and percent of
people perceiving a loss of
Shopping 37. Change in number of stores privacy. 8
and services, by type, avail-
able within x distance of y Overall Contentment 48. Change in percent of people
people. with Neighborhood who perceive their com-
munity as a good place to
38. Change in the percent of live.8
people generally satisfied
with local shopping condi- Fairness to All The above measures should
tions (access, variety, Groups be considered with respect
crowdedness).' to specific clientele groups
V. Housing and Social Conditions or population segments that
are affected to reflect the
Housing Adequacy 39. Change in number and per- quality of fairness in new
cent of housing units that developments.

NOTES:
1. These impact areas correspond to community objectives for regulating land development (see Exhibit 2).
2. In some situations, a measure of the change in the microclimate near a development should be added to the list.
3. Measures 5 through 10 also reflect aspects of aesthetics. See text for discussion of overlapping of objectives and interrelation of measures.
4. Some may find a new development physically attractive (Measure 14), but prefer the current appearance of the neighborhood for its
"character," image, relation to personal identity, and so forth.
S. Changes in the use of informal recreational facilities such as streets, sidewalks, and open space should be included.
6. No satisfactory measure of development impacts on the quality of education received has been found.
7. Impacts of land use changes on accessibility by foot are reflected in part in measures for recreation (25), schools (28), and shopping (37).
8. Measures dealing with citizen perceptions are much harder to estimate quantitatively for proposed developments than for past
developments. However, bounds or ranges may be estimated in some situations, and in all they should be considered at least qualitatively.

1. SUGGESTED IMPACT MEASURES

To assess systematically the future con- Generally, all objectives will not be advanced
sequences of proposed land development, each simultaneously by any single land development. As
local government should have its own set of impact some objectives are being furthered, others may be
measures. The measures should be practical to affected adversely. This is one of the reasons that
implement and understandable to nontechnicians. the basic list of objectives should be as broad as
The set of measures should be as short as possible possible.
yet comprehensive. Some communities may wish Realistically, the majority of people in a com-
to prepare their set of measures "from scratch," munity at any given time tend to be most inter-
based on their own local objectives. Others may ested in only a few of their obj ectives- usually
prefer to use the list suggested in this report as a those about which problems or opportunities are
starting point, which they would review and being publicized and discussed. These few ob-
modify to suit thier local purposes and values. In jectives are naturally accorded highest priority at
either case, it is necessary to,understand not only the time. But if the system employed by planning
what impact measures are, but how they are officials requires reference to a comprehensive set
formulated. of community goals, this should help guarantee
that none of the other objectives will be com-
STARTING POINT-COMMUNITY OBJECTIVES pletely ignored even though they may have low
One logical way of arriving at a set of meas- priority for a certain period.
ures is to start with a list of major community MEASURES TO MATCH OBJECTIVES
objectives. The goals should be expressed as ends,
not means, as targets, not strategies for reaching Once the objectives are determined and listed,
them. they can be used as a starting point for defining
Exhibit 2 presents an illustrative set of com- appropriate impact measures. An essential feature
munity objectives. The titles include the broad of the impact measures is that they assist in evalu-
areas of communitywide concern that are or could ating the likely outcomes of proposed develop-
be affected by patterns of growth and change. The ments in terms of each community objective.
statements accompanying each area of concern For example, maintaining the local govern-
attempt to encapsule enlightened views of what ment's fiscal solvency would be agreed upon in any
should be achieved. In sum, they represent what community as a legitimate objective. An obvious
those who frame the objectives consider to be the measure for testing progress toward this objective
ideal community. is the estimated net fiscal change that will come

about as a result of proposed developments. More balance between comprehensiveness and practical-
specifically, this measure requires that, for any ity. Therefore, the measures suggested do not cover
particular development, officials should estimate every minute aspect of each community objective.
the difference between the additional local reve- Emphasis has been placed, rather, on important
nues which the new land use will generate and the aspects most likely to be affected by development.
public expenditures which it will require, as com-
pared with the costs and revenues associated with SELECTING MEASURES FOR
the current land use. EVALUATING PARTICULAR DEVELOPMENTS
Similarly, if a community objective is to For each development case under review, all
maintain the present quality of local transporta- measures should be quickly reviewed.to detern-dne
tion, then measures might be chosen that will note whether they are appropriate. For few develop-
changes in travel time, parking availability, and the ments, however, will all measures need to be used.
accessibility of public transit. More detailed and comprehensive analyses
Exhibit I on pages 10 and I I shows the will in general be more appropriate for develop-
measures that have been identified for assessing the ments that are very large, for those that represent
impacts of developments with respect to the com- new departures in local growth patterns, for devel-
munity objectives previously outlined. Some ob- opments which could set important precedents,
jectives require more than one associated measure and for those which otherwise seem likely to have
for an adequate assessment, and some measures are powerful short-range or long-range effects. Groups
relevant to more than one objective.' of developments likewise will tend to merit use of
Local governments considering use of this list more measures and greater detail.
of measures might also scan the Appendix for
"other measures" which, although judged less For smaller developments, some simpler alter-
practical by the authors, may appear more suitable native forms of the measures are discussed in Part 2
for their own local circumstances. of this report. Many of the measures in Exhibit 1,
The measures delineated in Exhibit I can be nevertheless, can be used to evaluate smaller devel-
utilized for evaluating sets of objectives other than opments as well. Even when it is not appropriate to
those listed in Exhibit 2. For example, consider calculate everything quantitatively, some judg-
objectives cited in numerous rezoning cases: "pres- ments may be reached.
ervation of the character of the neighborhood" During the initial screening, the appropriate
and "retention of present life styles." While these subset of measures to use, and the level of analy 'sis
objectives are rarely well-defined, the context of needed for each, will vary from case to case.
their use in suburban communities indicates that Factors to consider in arriving at these subsets
they frequently refer to such things as retaining the include the following:
natural setting, avoiding crowdedness, maintaining
a feeling of security, maintaining the present socio- Type of Development
economic mix, and preventing traffic congestion. Some of the measures apply more to residen-
To assess the impact of new development from this tial than to commercial developments. Some apply
perspective, the following measures in Exhibit I more to suburban than urban development.
could be used: 7-8, 21-22, 25-27, 31-36, and
44-48. Likewise, those concerned- with "main-
tenance of a safe and stable neighborhood" might Local Conditions and Priorities
refer to Measures 21-24 and 41-42. At the time land use decisions are being
In defining and selecting an entire set of reached, local conditions will determine many of
measures, the attempt should be made to strike a the measures that require detailed consideration.
For example, measures of housing supply relative
1. Measures sometimes apply to more than one objective when to housing needs that would be crucial in times of
factors affecting the objectives overlap, as in the case of the
objectives regarding aesthetics and preserving the natural environ- housing shortages could be only briefly considered
ment. and checked off when there is an adequate supply

14 Developing and Using the Measures

EXHIBIT 2

COMMUNITY OBJECTIVES FOR REGULATING"LAND DEVELOPMENT'

1. Local Economy:

To keep the local government fiscally solvent without excessive taxes; to maintain a high level of stable employment
and to reduce unemployment and under-employment in the community; to maintain prosperity; and to enable citizens
in the community to achieve levels of personal income and wealth consistent with a decent standard of living (14).

11. Natural Environment:

To minimize pollution, protect wildlife and ecologically important features, preserve the natural environment, and
conserve scarce resources (5-12).

III. Aesthetic and Cultural Values:

To protect and improve the physical and cultural attractiveness of the community (5-10, 13-16).

IV. Public and Private Services:

* Health and Safety. To minimize illness, injury, death rates, and property loss or damage (5-7, 17-24, 35-36, 39).

o Recreation. To provide a variety of accessible and enjoyable recreational facilities and programs in the
community (6, 8, 25-27).

* Education. To provide quality education at all levels for all people in the community; to provide as diverse
educational experiences as the community requires; and to assure the convenience and pleasantness of attending
school (16, 28-30).

9 Local Ransportation. To provide access to an adequate choice of community services, facilities, and
employment in a safe, quick, and convenient manner; and to move goods efficiently (31-36).

Shopping. To promote the adequacy, variety, convenience and pleasantness of shopping for people
in the community (37-38).

V. Housing and Social Conditions:
� Housing. To increase the opportunity for all citizens to obtain satisfactory housing at prices they
can afford (39-40, 46-48).

� Social Concerns and Community Morale. To promote friendliness, psychological well-being, and good
community morale while protecting individual's privacy and ability to regulate their interpersonal contacts
(41-48).
� Fairness to All Groups. To apply each objective with equity to all within the community (1 -48, reported
by clientele group).

NOTES: 1. This set of objectives is illustrative. Each community should determine goals consistent with the desires and values of its citizens.
2. The numbers in parentheses following each objective correspond to the impact measures in Exhibit I which help describe
whether a development will contribute to the objective.
I The order of the objectives implies no ranking of priorities.

of satisfactory housing available for most income study, and may help ensure self-consistency among
levels. Similarly, a oommunity with abundant parks different parts of the evaluation. Similarly, when
and open space easily accessible to all population looking at other measures- changes in open space,
centers would not need to emphasize recreation housing, neighborhood appearance, and so forth-it
measures that would have high priority in cities is important to report all potential tradeoffs as ex-
with minimal outdoor recreation opportunities. plicitly as possible.
However, even when conditions are obviously satis-
factory, it might be good practice to note this in Costs
the summaries to let local decision makers know
the issue was considered and judged to be no In practice, the available resources-money,
problem. This will tend to reinforce an awareness time, skills, and tools-often dictate the level of
of, and a reliance on, the comprehensive approach analysis as much as the factors cited above. Costs
and help assure that unexpected problems will not will vary widely depending on the size of the sub-
be overlooked in these areas at some future date. set of measures used, the level of accuracy desired,
the availability of suitable methodologies and data,
What Is Being Displaced? the number of clientele groups for which distinct
impacts need to be charted, the experience of the
In assessing development impacts, although analytic staff, and the backlog of previous analyses
there is a natural tendency to pay most attention that can provide useful comparisons. The expendi-
to the proposed new use, the current land uses. that tures for evaluations also should be in line with the
would be displaced also need to be considered in size and importance of the developments to the
weighing the consequences. In the case of down- community. Identification of the costs and skills
town commercial buildings that will replace run- needed for varying levels of analysis is on the
down housing, for example, the proposal should be agenda of research tasks in the continuation of this
assessed not only in terms of what would be con- study.
structed but also in terms of the number and price
range of housing units demolished to make way for MAINTAINING PUBLIC SERVICES:
the development. Otherwise, the impact on the CAPACITY MEASURES
total housing stock of the neighborhood and city A prime concern of officials is that new devel-
might not be evident. opment will not so deplete the treasury or overload
Interrelationships and Tradeoffs the capacity of current facilities as to cause local
services to deteriorate. To reflect these concerns,
The measures of impacts are often strongly we have suggested measures of both public fiscal
related so it is important to consider them as a set. balance and quality of services. In the course of
A change in one measure may affect others. developing estimates for these measures, it is
Factors that at first may seem unimportant thus usually necessary to consider how the capacities of
should not be too hastily discarded. various public facilities will vary over time as a
To illustrate, consider that for many new result of development.
developments there is a tradeoff between govern- Capacity measures do not indicate direct
ment expenditures and the quality of public impacts on citizens so it is preferable to translate
services. The tradeoff often varies with time. For them into those terms-such as the likely incidence
example, certain facilities may be pushed to of water shortages based on the capacity of water
capacity by a new development before adequate supply networks. But when this is too difficult or
relief can be afforded. Often, quality is allowed to time consuming, the capacity data will serve as a
slip in the interim. It is therefore necessary to dis- useful surrogate. Even when the translation can be
cuss both the government expenditures and the made, it might still be useful to provide data on
quality of services, and how they will vary over capacities because they are operationally meaning-
time. Explicitly reporting both the fiscal balance ful, provide another easily understood perspective
and quality of services will help clarify the assump- on the impact of development, and will help
tions about service levels that went into the fiscal provide reasonableness checks and insights into the

16 Developing and Using the Measures

estimations made for the main list of measures. Capacities would be assessed for each facility likely
Also, the capacity measures should be quite useful to be impacted by the new land use, such as par-
in assessing cumulative impacts of groups of ticular schools or particular sewage plants. Where
proposed developments. specific facilities to be used by the development
Capacity measures should be stated in terms cannot be pinpointed, as is the case for facilities
of (1) the percentage of existing capacity utilized such as hospitals and sometimes parks, capacity
before the development, (2) the percentage of would be assessed for groups of facilities. Where
capacity to be utilized after development, and (3) private utilities are likely to be affected by new
the expected time until new capacity can be added development, the same kind of capacity measures
to relieve any present or anticipated overload.' may be applied. Examples and further discussion
of how capacity measures may be presented are
2. The decision to add new capital facilities is sometimes given in Chapter V.
beyond the direct control of local government, as is the case in most
California jurisdictions where special districts for fire or parks, for passed such hurdles and almost sure to be built, and facilities which
example, are common. In addition, voter approval may be required. are more speculative. The latter should be listed as likely to be
Thus distinction should be made between facilities already having available no.earlier than some specified date.

Suggested Impact Measures 17

11. HOW IMPACT MEASURES CAN
ASSIST LOCAL DECISION MAKERS

The ultimate test of any set of impact more fairly and constructively monitor public
measures is whether it can be used by mayors, city action on land use matters if some of the mystery
and county managers, city councils, county com- is removed from the evaluation process.
missions, planners and planning boards, zoning
boards, and other decision makers to arrive at Complementary to Existing Codes
better land use decisions for their communities.
The impact measures suggested in this report
are intended to complement, not to replace, the
EVALUATING PROPOSED DEVELOPMENTS
use of applicable local, state, and federal codes that
The measures should be useful to officials by help ensure the physical safety and sanitary condi-
providing them with the means for evaluat- tions of new building in most jurisdictions. These
ing what is seldom emphasized-the end results of codes include zoning, building codes, subdivision
development proposals from their constituents' regulations, health and sanitary codes, and fire and
perspective. Regular use of a set of measures for safety codes. Problems in safety and sanitation
evaluation has the potential advantage over present often arise through no fault of the codes but due
approaches of being more comprehensive, of pro- to their inadequate enforcement. The measures
viding more quantitative information about key provided in this report (Exhibit 1) do not duplicate
issues, of achieving more consistency by reference these safety and sanitation considerations on the
to the same framework and language, and of more assumption that local codes will usually suffice in
clearly identifying who gains and who loses.- these areas.
The measures thus provide a systematic basis for
helping public officials decide whether to accept or What Developments to Analyze
reject development proposals, to require
modifications, or 'to choose among alternative Governments usually will wish to use the
proposals that are competing for the same measures to assess only significant developments
resources. (not trivial items such as single homes or backyard
Local officials are also well served by making additions) and ones over which they have a
the measures widely known throughout the com- reasonable degree of control. The most common
munity. Developers and architects, armed with situations of this sort involve proposed develop-
knowledge of the evaluation criteria, are more ments requiring zoning changes- rezoning, zoning
likely to draw proposals that take account of basic variances, and special exceptions-as in the case of
community objectives. Concerned citizens also can shopping centers and standard subdivisions.

Planned Unit Developments (PUDs), which at- broader range of potential uses to which the site
tempt to accommodate higher population densities may be put if the rezoning is granted.
on parts of a site in order to provide more variety Another dimension to consider is the impact
of open space and community amenities on other of a proposed plan as compared with the impact if
sections of the site, appear especially well suited to it is rejected. Presumably each development is
impact evaluations. This is because they are usually intended to meet some demand. If not built, pres-
defined in more detail than other developments at sures are created to use existing facilities more
the stage when rezoning is requested, making the intensely or to develop elsewhere. This can lead to
analysis easier and more meaningful, and also increased housing prices, changes in migration
because the local government typically may patterns and so forth. Rejection of a proposed
exercise more control over the specifics of PUD development also does not preclude changes in use
plans. of the existing site that do not require government
Impact analysis may be particularly useful in approval. Thus the range of potential uses that are
situations in which local government officials are credible within the existing zoning should be
authorized to award incentives or bonuses in ex- considered.
change for features deemed to be in the public While the complexities and high costs would
interest. In commercial areas, for instance, builders limit the feasibility of carrying out comparisons of
might be permitted to add one or two floors above all such alternatives in detail, modest efforts in
the usual height limits in return for providing these directions will counteract the unrealistic
amenities for pedestrians. notion that the alternative to a proposed land use
Even if no regulatory tools are applicable, and is zero change in the community, or that the
no -hazard is created by the development, a local proposed development will not change consider-
government may still find it advantageous to ably before it is constructed.
evaluate a proposed development. The findings
from such impact studies may be presented to the Initial Screening
developer directly as a device for encouraging self The advisability of a quick review of each
regulation or they may be announced publicly to proposed development against the entire check list
,bring community pressures to bear. of measures, referred to in the previous chapter,
For example, local officials might evaluate bears underscoring again. Local officials should
developments that seem likely to alter the com- conduct an initial screening of development
munity's revenue status and the pattern of de- proposals to deten-nine whether they meet various
mands for services plus those developments that codes and conform to community plans. If flagrant
may set other. precedents regardless of which conflicts are found, no further examination is
specific controls can be applied. needed.
Range of Development Options to Consider If a proposal passes this kind of test, a second
screening of the impact measures will indicate areas
In some situations, more than one develop- -that raise the most serious questions and that
ment option for a particular site or several sites require detailed data gathering and analysis.
may be evaluated simultaneously. The impact
evaluation must consider not just the potential When Quantification Is Weak
changes from the existing baseline, but also the
merits of the various options relative to each other. Does the measurement system fall apart and
In some jurisdictions, developers have con- become useless in those cases when quantification
siderable latitude to make major changes in their is difficult or impossible? Not at all. Admittedly,
plans as originally proposed and approved, so long there will be many instances when intensive data
as these fall within a range of uses permitted within collection for certain measures is not feasible.
the new zoning category. An evaluation of future Nevertheless, the specific consideration of each
impacts in such communities should consider not item on the checklist, even if it is only assessed
only the proposed development, but also the qualtitatively, is likely to improve evaluations. For

20 Developing and Using the Measures

instance, simply to raise issues of aesthetics, they have some way of keeping track of how dif-
privacy, or use of streets for informal recreation, ferent groups in their community are in fact
even if the anticipated changes cannot be cal- treated. For this purpose as well as several others,
culated with much precision, is more likely to set the measures should be used to assess impacts of
in motion the desired public and private improve- development in terms, not only of the city or
ments than if the matters were completely ignored county as a whole, but also for distinct segments of
during the approval stages. the population. This is considered of such current
importance that a separate chapter-Chapter IV-is
Weighing the Measurement Results devoted to an elaboration of this point.
The system of impact measures proposed in Spillovers-the impacts of development and
this report is not a mechanistic approach; rather, it land use decisions that affect neighboring jurisdic-
relies in the final analysis onjudgments. The impact tions or other parts of the metropolitan area-may
measures cannot be inserted into a formula that be considered an extension of the concern for all
clientele groups. These too are discussed further in
will give an automatic answer to whether a the next chapters.
proposed land use change should be approved or
disapproved. In particular situations,, any one Who Should Undertake Evaluations?
measure could become of great-or even primary-
importance; yet the same measure may be insignifi- The responsibility for data collection and
cant in other times or circumstances. An a priori analysis may be assigned to local gove rnme nt staff,
assignment of weights to each measure would to contractors or consultants, or to responsible and
therefore seem more likely to obscure than to broadly based citizen groups. Developers inevitably
clarify, and is not recommended. Instead, the find- must be relied on for at least some of the data
ings must be considered by officials and concerned including design plans and projections for future
citizens in light of what they already know about use.
the individual assets, needs, and political realities In any case, it is important that local govern-
of their own community. In short, this system is ment officials select or review the measures to be
intended to assist decision makers by giving them a applied in a particular case and that data collection
way of obtaining improved information within an and analyses supplied by developers be carefully
organized framework; they, not the system, must reviewed by the local government to maintain
weigh the factors in each case.' credibility of the results.

Clientele Groups and Spillovers EVALUATING PAST DEVELOPMENTS

One of the prevalent urban movements of this The land use measures suggested in this report
era is the persistent demand for equitable treat- are designed for use in evaluating the actual
ment. Neighborhoods, racial and ethnic groups, impacts which have already occurred from previous
and persons of certain age categories often feel developments as well as those likely to occur from
alienated because Oustly or otherwise) they sense the proposed developments. Retrospective evalua-
that they are receiving poor service or insufficient tions by local governments of previously com-
consideration by their government. Elected local pleted development have been rare, although they
officials and their staffs, even if highly motivated are beginning to be undertaken more frequently.
to meet this objective, may run afoul of it unless They hold the promise Of providing valuable feed-
back for those involved with impact evaluation.
For example, they might be used for the following
1. An excellent, detailed discussion of the tradeoff problem purposes:
and of various formal approaches for making a decision in light of
incommensurable data may be found in Douglas C. Dacy, Robert E.
Kuenne, and Martin C. McGuire, Approaches to the Treatment of 0 To compare actual impacts with what
Incommensurables in Cost-Benefit Analysis: Prepared for the Na- the developer estimated or claimed when
tional Science Foundation by the Institute for Defense Analysis,
Program Analysis Division, Arlington, Virginia, 1973. the proposal was made. As confidence is

Assisting Local Decision Makers 21

gained in the measurement procedures, may project the individual elements of a
the comparisons might even become a proposed development with some ac-
basis for rewards or penalties to de- curacy but still fail to predict some of
velopers. Those who comply with or the overall effects that will come to light
exceed their promised landscaping or only after it is completed.
parking arrangements, for example, may Full retrospective analyses can be expensive so
become eligible for performance local jurisdictions must be highly selective in
bonuses. Those who do not comply undertaking them. But their high potential for
might be penalized or held to more con- revealing insights on the effects of development
crete assurances in their future develop- should not be ignored.
ments. The intent would be to improve Certain obvious differences will occur in
the quality of predevelopment estimates applying the measures to future and past develop-
by the developers and to encourage their ment. For past developments, data collection and
continuing interest in their projects (in analysis can focus more on measurements of actual
contrast to a "hit-and-run" attitude). changes than on estimates, although there is often
a problem of attributing changes to the develop-
To monitor the quality of the local gov- ment rather than to other factors. Assessments of
ernment's decision making, again by future developments, however, must rely more on
comparing actual impacts with those pre- estimations. The direct measures that can be used
dicted. Of course, many factors change for tracking impacts of past developments must
over time, so the fact that different re- sometimes give way to proxy measures when
sults occur than were predicted -either efforts turn to forecasting. For example, wildlife
by developers or officials-does not surveys made before and after development can
mean that the original decision was help indicate the change in wildlife abundance due
necessarily inappropriate. to past development. However, forecasting changes
To use th .e past to help predict the in wildlife due to proposed development may often
future. As a community completes be too complex, and a proxy such as the change in
studies of different types of previous available acreage of habitat may have to be used
developments, the findings will provide a instead. Building a repertory of retrospective evalu-
series of case histories that, if carefully ations should help local governments estimate end
used, can help indicate the most likely effects rather than proxies.
impacts when similar plans and circum-
stances are going to reoccur. Often, EVALUATING COMPREHENSIVE AND
reasonable quantitative projections can- NEIGHBORHOOD PLANS
not be made except by this kind of
analogy to past experience, as in trying The use of impact measures to assess specific
to assess citizen perceptions of crowded- developments is the main thrust of this report, but
ness or neighborhood pleasantness. the measures proposed here also may be used-with
Retrospective evaluations would be even minor variations-to help evaluate comprehensive
more useful if they were generated by plans, neighborhood plans, and other area plans.'
groups of similar communities so that a This application of the measures to land use plans
broader data base could be generated. A is even more suitable in some respects than to
cooperative venture of this sort might be individual developments. More resources can be
undertaken under the auspices of muni-
cipal, county, or state professional
associations.
2. One example of the use of a set of measures for evaluating
comprehensive plans is described in the Southeastern Wisconsin
0 To give greater insight into direct and Regional Planning Commission, Report No. 7, Volume 2, circa
synergistic effects of development. One 1963.

22 Developing and Using the Measures

devoted to the task and some of the techniques values within the community. Despite these prob-
lend themselves more readily to detecting large- lems, the use of impact measures within this con-
scale impacts. text nevertheless appears worthwhile.
Applying a full impact analysis to general Local governments, going further, may find
plans, however, is not without its difficulties. Such that they can strengthen their comprehensive land
a wide range of developments usually can occur use plans by imbedding within them quantitative
within the limits defined by a given plan that a targets or constraints related to many of the
large number of alternative projections have to be impact measures. If this were done it would
made and the degree of uncertainty may be con- provide an excellent yardstick for evaluating in-
siderable. Although bounds can be developed for dividual and cumulative effects of proposed
many measures, they may of necessity be fairly developments. Much baseline data useful for evalu-
gross. Comprehensive plans are usually made to last ating individual developments, such as natural re-
for several years, yet long-range estimates may be source inventories and maps showing the existence,
invalidated by changes in technology (e.g., vehicu- capacities, and extent of utilization of public facili-
lar pollution controls), the emergence of new prob- ties, can be generated in the process of creating and
lems (e.g., the energy crisis), or altered mores and updating comprehensive plans.

Assisting Local Decision Makers 23

-111. PUTTING THE MEASURES
IN PERSPECTIVE

To avoid an overly simplistic view of the conditions, (2) potential impacts resulting from
impact measures and their application to land use changes in the use of present structures and facili-
decisions, several complex but important issues ties, as when a maturing community with a
need to be stressed. Some of these have been declining birth rate demands fewer classrooms, and
touched on in earlier chapte rs and are explained (3) future land use changes that are likely to occur
more fully here. The discussion that follows, never- in the community, including other proposed devel-
theless, still only skims the surface, but aims to opments. This context is especially important for
raise certain caution signals. The issues fall into local officials to keep in mind when they are
two broad categories: making separate decisions on each request for land
use change.
0 Relating the estimated impacts of specif- The collective impacts are important for
,ic developments to the community and several reasons. First, individual development deci-
region at large, taking account of the col- sions often combine in complex ways. Their total
lective effects of series of developments impacts, in respect to many social, economic,
over time. public service, aesthetic, and environmental
measures, are not simply additive, but may amount
Paying attention to hard-to-evaluate in- to something more than and different from the
stitutional, procedural, and political sum of their parts. Extensive development may
problems, some of which may be caused lead to fundamental changes in the community.
by the introduction 'of an explicit, well- For example, a semi-rural community on the peri-
defined set of impact measures itself. meter of a metropolitan area often can maintain its
small town character with the addition of a few
RELATING IMPACTS TO THE small residential or commercial projects. But at
COMMUNITY AND REGION AT LARGE some point in the growth cycle as more and larger
developments occur, the character of the popula-
Collective Effects of Development tion and its demands for public services may
change substantially, requiring changes in the struc-
Many impacts of a specific development or ture of public services. For instance, a volunteer
set of developments often can be assessed realisti- fire department may give way to a fulltime profes-
cally only with the context of (1) cumulative sional one. Or the number of police per capita and
impacts of past developments, such as the current their form of organization may change, not just
air quality and public perception of community because crime rates often increase as communities

grow, but also because of new demands for services boundaries of their immediate jurisdiction. Ex-
such as traffic control. Considerable evidence in- amples are water pollutants dispersed through a
dicates that the unit costs of public service change drainage network, or air pollutants emitted into an
as a jurisdiction's size and population density in- air shed-they seldom disappear neatly at political
crease. In short, the whole tenor of community life boundaries. Likewise, industrial and commercial
may be transformed. developments typically draw labor force and con-
These kinds of change, however, are not usu- sumers from beyond the municipality where they
ally attributable solely to single developments are located, which may produce favorable or un-
unless they are large relative to the existing com- favorable consequences for their communities.
munity. For this reason, the application of impact Many of the measures listed in Exhibit I
measures to individual developments needs to be could apply to regional as well as local impacts.
viewed within the context of an area's total urban However, the regional effects of individual develop-
growth process lest the forest be lost for the trees. ments are often too diffuse to isolate. Thus, even
A second major reason for considering collec- more so than at the community level, the collective
tive effects of developments is that the impacts of impacts of regional development need to be con-
a single land use change on some important com- sidered for a proper perspective of spillovers and
munity characteristics is often inconsequential. For counterbalancing spill-ins.
example, the contribution to air pollution of 200 Unfortunately, a governmental agency for
new units of housing,.though measurable, is likely assessing greater-than-local development impacts
to be quite small. In some situations even small often does not exist. Local governments have little
changes could be important-as when the pollution incentive other than a sense of fair play, and a
level is already approaching or exceeding some hope that their neighbors will reciprocate, to spend
definable critical point. More commonly, however, the effort-and it is likely to be considerable-in
it would be necessary to evaluate not only the 200 examining spillover effects beyond their borders.
new houses but the entire group of proposed or Councils of governments, regional councils, and
anticipated developments over the next year or so some units of state government are starting to fill
for their collective impact on air quality. The. this void for some classes of development. But in-
assessment, of course, should also take into ac- stitutional and political barriers that discourage
count any likely changes in existing community cooperation among neighboring communities and
activities or regulations that may affect emissions, the technical difficulties of gathering and analyzing
such as increases or decreases in car trips per per- data on metropolitan-wide impacts still pose major
son, new pollution controls on cars, changes in hurdles to adequate consideration of spillover
public incineration, and so forth. effects.
A third major reason for considering collec-
tive impacts is that some proposed developments Secondary Impacts
mi,ght counteract the positive or negative effects of New developments frequently induce ad-
other proposed developments. For example, an ditional economic activity. Industrial and com-
urban renewal prqject that proposes a park for mercial growth often attract inmigration which
small children could receive high grades on that translates into demand for new housing and
account. But another development proposed in the shopping centers. These demands stimulate ad-
vicinity of that park might make traffic so hazard- ditional construction, both private and public. All
ous as to render the park inaccessible to small these activities have environmental, social, and
children. Unless both projects were considered economic impacts.
together, unrealistic and unreliable forecasts would Local government has some subsequent
be obtained. control over these ripple effects or secondary
Spillover Effects impacts. For example, officials have the alternative
of disapproving land use change requests that are
Many large developments have significant stimulated by previously approved developments.
environmental and economic effects beyond the However, such refusals themselves can have

26 Developing and Using the Measures

secondary effects. In the case of industrial de- viously untouched area or a major change in the
velopment, suppose that requests to rezone intensity of development:
land for housing to meet residential demands
generated by the new industry are denied. This 0 The first residential subdivision in a
would tend to cause prices of existing housing to farmland area.
rise. Some families, particularly those in the lower
income range who could no 'longer afford the 0 The first highrise in a single-family home
higher housing costs, may be forced to leave the neighborhood.
community. This could cause a drop in school
attendance or in the demand for other public 0 The first development on a strip of virgin
services, and a whole chain of effects in the public beach.
and commercial sectors.
Although the significance of secondary effects The first construction in a forested area.
of development has long been recognized, fore-
casting and measuring these effects with any Another type of precedent, often a result of
precision still appears to be beyond present one of the above, is the first major deviation from
capabilities. Analysts have attempted to incor- the existing comprehensive plan. This may lead to
porate projections of secondary effects in urban further deviations, which could accelerate the
computer niodeling without a great deal of success. erosion of the plan. This may not necessarily be
Yet it seems desirable, as part of land use impact detrimental, but as a possible long-term effect of
measures, to do one's best to anticipate the the land use decision at hand, such an important
possible kinds of secondary impacts that may direction should be taken deliberately, not merely
occur and to estimate them at least qualitatively, entered into by default.
and to note the directions and orders of magnitude A totally different type of precedent would
of the impacts where feasible. When such an be the adoption by a city or county of a new
exercise suggests that the secondary effects will be standard for evaluating land use questions, as
substantial, this inforination should be included would be the case the first time that impact
along with the direct measurement data presented measures comparable to those proposed in this
to the decision makers. report were revealed to the community and put to
use. Once the explicitly stated new measures are
used to evaluate a development, it may be difficult
INSTITUTIONAL, PROCEDURAL, to change or abandon them in future cases without
AND POLITICAL ISSUES the government being subjected to charges of
unequal treatment or capriciousness. So a com-
Precedents munity should exercise care to choose a set of
A land use decision which sets precedents for measures that is likely to be stable for some time.
the future may assume an importance far greater Political Problems
than would be implied by any immediate impacts
of the specific development as reflected by the At least one potential political problem that
measurement data. Once an approval of this kind is may arise from the application of land use impact
made, it can be extremely difficult to reject measures needs to be highlighted: their use could
proposals for similar developments. The builder increase community conflicts, at least in the short
may appeal not only to logic-that he is following run. This is because explicit, quantitative data may
suit in a pattern already endorsed by the bring to light problems and inequities that were
authorities-but also to the law, claiming that equal previously unknown, unmentioned, or only vague-
treatment provisions support his right to do what ly sensed. This is especially likely when impacts on
another developer was allowed to do. various clientele groups are reported.
A number of potentially precedent-setting For example, the data may spotlight a public
situations often involve development of a pre- fiscal loss associated with a proposal for low-

Perspectives 27

income housing or the negative environmental resources, at least initially. It might also increase
impacts from a new job-creating industry. Decision costs to the developer because of increased data
makers who strongly favor the improvement of requirements levied on him or from additional
housing and job opportunities may consider it delays in arriving at a decision on his proposals.
undesirable and contrary to the community's best These costs may be passed on to consumers.
interests to publicize information that could arm Systematizing and documenting the impact evalua-
the opponents of low-income housing and tion process, however, might conceivably result in
industrial growth. lower overall analysis costs and time-that is, the
On the other hand, making the evaluation sum of developer, public sector, and private citizen
more explicit, quantitative, and comprehensive costs. Each evaluation, for instance, would be
may help lay some community fears and myths to somewhat less of a special study with its own
rest. For instance, concerns about increased traffic models, tools, and approaches than is the case
or pollution might be allayed if the degree of today. The proposed system offers the potential
anticipated increases were spelled out. In the long for creating computer models and survey instru-
run, a more open and intelligible decision making ments that, once in existence, could be applied to
process should improve the quality of decision many development decisions. These analytic tools
making. Equally important, such an open policy also may be offered by local government to
should help restore confidence in government-the developers, consultants, and other private interests
lack of which is certainly one of the more serious for their own purposes, possibly on a fee-for-
ills of current American society. service basis.
Information Overload and Aura of Precision But the main reason for using a more
systematic approach is to improve the quality of
The use of a large set of impact measures has land use decisions. That is where the largest
the potential danger of overwhelming or bewilder- potential savings to the public lie. Without having
ing decision makers with information about more some belief that this will be the result, it would be
aspects than they can grasp. Fears also have been hard to justify adoption of the system on cost
expressed that masses of statistical information arguments alone.
might convey to officials and citizens a misleading
appearance of precision so that undue reliance
would be placed on the estimated impacts. These On balance the risks involved in using the
dangers, while real, are common even to current measures and the inability to resolve adequately all
procedures and to most management information the issues discussed above seem less serious than
systems. To be alert to the dangers is the first step the problems associated with failure to move ahead
toward minimizing them. on improvements of the current land use decision
The comprehensiveness and depth of analysis process. Each local jurisdiction obviously must
that can be absorbed by decision makers depend consider the many tradeoffs from its own vantage
on several factors-the care taken in developing point.
data formats that can be quickly understood; the A point which would not have had to be
degree to which technical data are translated into made until recent years is that a good deal of the
meaningful descriptions of future impacts on discussion in this report about the complexity of
citizens; and the attention given to educating local growth should not necessarily be interpreted as
officials about data collection procedures and the arguments against community changes. Many
measures that will be regularly presented to them. citizens and interest groups, frustrated by the
These factors may be as critical as the improve- shortcomings and disappointments of current land
ment of data gathering and analytic techniques. use practices, are indeed taking this position. The
point of this report is not so extreme or absolute.
Delays and Costs in Decision Making Rather it holds that the options for change should
The work of collecting data for the proposed be examined more carefully and systematically,
measures and setting up new procedures is likely to and selected with more discrimination than often
require additional governmental staff time and has been the case.

28 Developing and Using the Measures

IV. CLIENTELE GROUPS

The impacts of development do not fall approach also may help officials to identify aspects
evenly across a community. As a result of changes of proposals which require modification before
in land use, benefits are enjoyed and losses are plans should be approved. Over the long run, it
suffered in various ways and to various degrees by should help indicate when the burdens posed by
many different groups-such as the owners of the development, instead of being shared uniformly,
development site, nearby residents, commercial are being borne to too large an extent by particular
interests, and persons being displaced. groups. Impact analysis by clientele groups might
When development proposals are being also serve to further the dialogue between decision
reviewed by officials, some of the affected groups makers and citizens although, as noted in the
and individuals present arguments pro and con. previous chapter, explicitness may carry its own set
These persons who have the time, awareness, of potential difficulties.'
know-how, and economic wherewithal to come For various land use proposals, different sets
forward may not represent all of the numerous of clientele groups need to be considered. The
groups having an important stake in the decisions. pertinent groups depend on the type, size, and
For example, low-income families and residents or location of the development. The clientele groups
small businesses just beyond the immediate that follow in outline form (see also Exhibit 3) are
neighborhood of the development site often do not merely suggestive or dlustrative of the ones that
have advocates at the hearings to represent their may be appropriate in any given situation. The
views and interests. clientele groups are described briefly. Some of the
Evaluations of development, therefore, should issues that merit consideration for thes'e groups are
not be limited to estimating communitywide listed; in most cases the link between these issues
impacts. They should also attempt to identify and the impact measures discussed earlier should
significant impacts on distinct clientele groups be obvious. The assessments from the perspective
within the community, and preferably on groups of clientele groups will be more valuable to
outside the community as well. officials if the size of each group for which impacts
Identifying impacts on various clientele
groups should help clarify how the beneficial and
detrimental effects of development are distributed 1. The mechanisms for increasing public involvement in land
use planning, with particular attention to the balancing of active
and prevent a positive effect on one group from interest groups, affected interest groups, and the general public,
being offset by a negative impact on another. The have been studied by Nelson M. Rosenbaum of The Urban Institute.
See Nelson M. Rosenbaum, "Citizen Involvement in Land Use
negative impact may not be noticed if the impacts Governance: Issues and Methods," Working Paper 0785-04. The
are reported as an average across all groups. This Urban Institute, Washington, D.C,, July 1974.

EXHIBIT 3

CLIENTELE GROUPS POTENTIALLY AFFECTED BY DEVELOPMENT

Physical Proximity

Persons living or working on the land proposed for development
Persons living or working immediately adjacent to proposed development
Persons in neighborhoods surrounding the proposed development
Persons within commuting distance (one hour by public transit, for example) from
proposed commercial and industrial developments

Business Relationship

Builders, realtors, bankers, and others directly involved in the development
Owners and managers of businesses or property in the neighborhood

Political Jurisdiction

Citizens of local jurisdiction containing the development
Citizens of immediately adjacent jurisdictions and of entire metropolitan area

Citizens of the state and nation

Socioeconomic and Demographic

Age groups
Racial and ethnic groups
Persons of various income levels, from poor to affluent

Other Interest Groups

Tourists

Land owners

Others

The Long-Term Public Interest

All present groupings over time
Future generations

NOTE: This list of population segments that merit consideration is illustrative and is not all-inclusive for every situation. Many other
categories will be readily apparent within the context of specific impact measures. For example, in considering transportation
impacts, an important distinction to make is between persons and families with and without automobiles.

are reported is indicated in summary charts for Issues: Those in this group vary ac-
decision makers, as illustrated in the next chapter.. cording to the type of development. For
The groupings listed are not formal organiza- a work center, the people included are
tions, associations, lobby groups, or the like. those within the locally acceptable
Rather, they are categories of people or interest commuting distance or time-for ex-
groups that are likely to be affected in different ample, one hour by public or private
ways by development. transportation. For a regional shopping
center or amusement park, the people
A. GROUPINGS BY PHYSICAL PROXIMITY may include those in a much larger area.
TO THE DEVELOPMENT Note that the number of people within
commuting distance cannot fairly be
1. Persons currently living or working on assessed until the effects of the develop-
land to be developed. ment itself on public transit service, new
roads, and traffic congestion are es-
Issues: Availability, accessibility, quality, timated. Note also that the area under
and cost of relocation housing. Earnings discussion may include most or all of a,
at new jobs. Disruption of social ties. metropolitan area and, in some in-
Changing schools for children. Relative stances, multistate areas. Among the
satisfaction with the neighborhood in many relevant measures for commercial
likely new locations. or industrial developments are changes in
employment, recreation, shopping avail-
2. Persons living or working on land ability, travel times, and pollution @along
adjacent to the development. commuter corridors. Residential devel-
opments need to be assessed in terms of
Issues: Almost all measures (Exhibit 1) available housing relative to job
are relevant for this group. locations.

3. Persons living or working in neigh- B. GROUPINGS BY BUSINESS RELATIONSHIPS
borhoods around or near the develop- TO THE DEVELOPMENTS
ment. 1. Businessmen directly involved in the
Issues: Most measures are relevant for development, such as builders, realtors,
neighborhoods-which may be defined and bankers.
by well-mapped boundaries (as in the Issues: Businessmen may be concerned
case of neighborhood service areas), by with a wide range of economic, social,
socioeconomic characteristics of resi- and environmental changes that will
dents, or by proximity to the develop- affect the profitability and safety of
ment, such as "10 minutes walking their investment and their reputation in
distance." Traffic, crime, air and water the community. Most impact measures,
pollution, and crowding of major rec- not simply the economic ones, are of
reation facilities are among effects that interest.
may spill over into several neigh-
borhoods. Impacts on noise, views, 2. Owners and managers of businesses or
sociability, and privacy tend to be more property in the neighborhood.
localized (but this should be checked
against the size and design of the specific Issues: Number and mix of potential
proposal). customers, new business competition,
public safety, property values, quality of
4. Persons within commuting distance or public services, and environmental im-
usage range of the development. pacts.

Clientele Groups 31

C. GROUPINGS BY POLITICAL D. GROUPINGS BY SOCIOECONOMIC AND
JURISDICTIONS AFFECTED DEMOGRAPHIC CHARACTERISTICS
BY THE DEVELOPMENT
I Citizens of the local jurisdiction. I. Age groups, such as children and the
elderly.
Issues: Changes in taxes, community Issues: Education, traffic safety, recre-
fiscal solvency, local ec 'onomy, em- ation for children. Public transit, hous-
ployment, public service quality, crime, ing, noise and pollution, health hazards,
natural environment, and so forth.
neighborhood social conditions, recre-
ation, and crime protection for the
2. Citizens of nearby local jurisdictions elderly.
and/or of the entire metropolitan area. 2. Ethnic, racial, and religious groups.
Issues: Basically the same impacts
affecting the jurisdiction where the Issues: Equal opportunities for housing,
development will occur also need to be education, recreation, and employment.
considered for possible spillover effects, Neighborhood social composition.
of which economic, pollution, housing,
and transportation impacts are often 3. Income groups.
among the most important.
Issues: Housing and employment oppor-
3. Citizens of the state. tunities.

Issues: State taxes and revenues. State E. OTHER INTEREST GROUPS
public services. Regional environmental
changes. Statewide employment and I . Tourists.
housing patterns. Attractiveness of
state's industrial climate. Important state Issues: Landmarks, scenery, shopping,
landmarks or scenic attractions. Energy public safety.
consumption.

4. Citizens of the nation. 2. Land owners.

Issues: Federal taxes and outlays. Multi- Issues: People who own property,
regional pollution. Overall housing and whether for u 'se or for investment, have a
employment opportunities. Impacts on special interest in the local economy, the
minority and low-income groups. Pres- tax climate, and the cumulative land use
ervation of national landmarks. Scarce impacts.
resources. Cumulative effects and
development trends will generally be of 3. Distant viewers of the development.
more concern nationally than will the
impacts of single developments. In- Issues: People at some distance from a
novative features of the development, of development site (across the river or on a
the zoning, of the decision making mountain overlooking a valley) should
process, and of criteria used-and court be considered if the changed land use
opinions on any of these aspects-are of will block their view or create (or
widespread interest. remove) an eyesore.

32 Developing and Using the Measures

F. THE LONG-TERM PUBLIC INTEREST Most of what has been said about the use of
impact measures in general applies to the measures
Issues: Considering this group focuses when they are seen from the perspective of
attention on future generations and on clientele groups. These interest groups should be
all groupings over time. Enduring im- used first as a check list for a quick screening so
pacts on the physical environment, that none are forgotten. Time and money may be
waste of natural resources, tax trends, conserved in evaluations by narrowing this list to
pollution, wildlife, landmarks, and aes- smaller subsets of clientele groups likely to be
thetics all assume greater importance affected most significantly before launching into
from this perspective. more detailed analyses.

Clientele Groups 33

EXHIBIT 4

ILLUSTRATIVE DISPLAY OF IMPACT MEASURE DATA

Hypothetical Proposal: 20-story office budding with shopping plaza replacing tenement housing
IMPACT ON CLIENTELE GROUpS2

A. Local Juris- B. Immediate C. Low-Income Families
IMPACT AREA MEASURE' diction Neighborhood in the Jurisdiction
(50,000 people) (500 people) (5,000 people)

Local Economy (1) Change in net fiscal flow +$200,000 N/A3 N/A
to $300,000

(4) Net number of new jobs +200 to 300 +10 to 20 jobs +50 to 70 jobs
jobs
--------------------------------- -------------------------
Aesthetics (15) Number of people whose 300 to 400 250 to 300 250 to 300 people
views will be blocked people people
(16) Percent people (in random 75% (of 40% (of N/A
survey) finding development sample) sample)
attractive

------------------------- ---------------------------------
Air (7) Number of additional +4000 to 8000 + 300 to 500 N/A
Pollution people expected to be ex- people people
posed to x p.p.m. for over
y hours more than z
times a year

-------------------------- ----------------- -----------------
Local Trans- (37) Change in average +3 to 5 min. +3 to 5 min. N/A
portation auto travel time to
reach destination x
in neighborhood

-----------------------------------------------------------
Housing (42) Change in number of -50 sub- -50 sub- -50 substandard units
Stock housing standard units standard units

----------- -------------- ----------------- - ------------- -
Neighborhood (48) Number of residents 150 150 130
Stability displaced

1. Numbers in parentheses refer to measures in Exhibit 1.
2. See Chapter IV for a discussion of clientele group interests. These are illustrative of only a few clientele groups; others would also be pertinent
people may be in groups A, B, and C.
3. An estimate of whether the remaining families in the neighborhood will pay more or less property taxes due to changes in property value might

V. DATA PRESENTATION FORMATS

Information obtained for evaluating proposed likely outcomes. The data also should show
land developments in accord with the system whether each estimated impact appears to be
suggested . in this 'report often can be quite consistent with targets included in the com-
extensive. To make this information as intelligible munity's comprehensive plans. When available and
as possible for the responsible public officials-and appropriate, standards set by various government
other users-requires special care in the form of its agencies or professional groups should be included
presentation. Some initial thoughts on displaying as frames of reference for judgment, and values
impact data are described here. that exceed acceptable limits should be flagged.
As earlier chapters have emphasized, the Additional columns should be added to the
measures do not provide a means for automatic exhibit to indicate the cumulative impacts of a set
decisions but rather provide the basis for informed of developments proposed for the same time
judgments by giving officials and their staffs the frame. While the air pollution impacts of a single
pertinent facts of the cases. These facts must then proposal might be fully acceptable, the overall
be evaluated in light of the decision makers' effect of the series of proposals might appear so
understanding of local conditions, problems and critical that modifications would be needed in each
objectives. individual plan.
In addition to the main exhibit summarizing
IMPACT MEASUREMENT DATA impacts, charts with further details should be
The presentation of the facts succeeds to the provided as back-ups. These might include before-
extent that it makes it possible for the viewer to and-after air quality contours, travel time contours,
visualize and keep in mind a wide variety of employment levels by skill category, and the
findings. One format for displaying the data in a details of cost-revenue analyses, depending on the
case.
meaningful way that can be readily grasped is
shown in Exhibit 4. PUBLIC FACILITY CAPACITY DATA
Data are displayed for each relevant impact
measure and for each appropriate clientele group. A back-up exhibit of particular importance in
Where possible, ranges should be given for each many instances is one that will show the degree to
measure that has considerable uncertainty; this will which a development impinges on the capacity of
prevent too much weight or importance from being local government facilities and of private utilities.
attached to data that may be dubious and will help The relation between impact measures and capac-
indicate the possibly large variety of reasonably ity measures is described on pages 16-17.

EXHIBIT 5

CAPACITY OF PUBLIC FACILITIES

Percent of Existing If Overload, Earliest
Capacity Used Time of Relief
Type of Public Facility' (in months)

Before After
Development Development

1. Main sewage and storm drainage
network in the neighborhood

2. Sewage treatment plants

3. Water pumping station

4. Schools

5. Police and fire stations

6. Solid waste disposal facilities

7. Recreation facilities (pools, parks, etc.)

8. Hospitals and other health facilities

9. Major roads

10. Libraries

11. Gas and electric plants or
distribution networks

12. Other (specify)

1. Data should be reported separately for each facility within a type where changes to individual facilities from development can be
identified. Under schools, for instance, three elementary schools, two junior highs, and one senior high might be affected. Where a development
will be developed in phases, the capacities should be reported by phase.

Exhibit 5 illustrates a format for presenting A more comprehensive version of this exhibit
the capacity data. The types of facilities listed would include the availability of adequate
down the first column include those which personnel to staff facilities, in addition to the
knowledgeable people believe might be affected by provision of physical plant. There may be ample
a proposed new development. The next column classroom space for additional school children, for
shows the percent of existing capacity being used. instance, yet the quality of service may suffer
If it is already being used close to-or beyond- seriously if the school system has not allowed
capacity, this is a warning that local government sufficient lead time for recruiting and paying for
must (a) immediately begin adding to capacity, additional teachers. Similarly, additional police and
(b) disapprove the development, or (c) warn fire personnel require training and cannot be
citizens that the new development will entail a produced overnight to fill needs.
decrease in the quality of public service. If the The graphic presentation of capacity measures
percent of capacity after development appears will not only assist officials in deciding land use
critical, then the same kinds of choices must be cases. It will also dramatize the importance of
considered. The final column, showing the earliest capital improvement programming and budgeting
possible time at which new capacity could be as an integral part of the community land
available to relieve any overload problem, puts all development process.
of these decisions into a meaningful time frame.

Presentation Formats 37

PART 2: IMPACT MEASURES-
ANALYSISANDDATA
COLLECTION APPROACHES

CONTENTS PART 2

Page

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43

1. ECONOMY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45

Public Fiscal Balance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Revenue estimates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Operating expenditure estimates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Capital expenditure estimates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Employment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Industrial and commercial development . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
Residential development . . . . . . . I. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Stability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . 54
Wealth . . . . . 54
Type of new development . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Number of households in the development . . . . . . . . . . . . . . . . . . . . . . . . .,. 55
Remaining land available for development . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Availability of public facilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . 55
Property taxes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Physical characteristics of land . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55

11. NATURAL ENVIRONMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Air Pollution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Estimating emissions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
Estimating air quality changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Estimating the number of people affected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Water Pollution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Noise Pollution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
Greenery and Open Space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Wildlife and Vegetation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Scarce Resource Consumption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Electricity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Fuel oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Natural gas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Gasoline . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Natural Disasters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66

Ill. AESTHETICS AND CULTURAL VALUES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69

Views . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Attractiveness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Landmarks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71

Page

IV. PUBLIC AND PRIVATE SERVICES ................................... 73

Drinking Water ................................................ 73
Hospital Care ................................................. 74
Crime Control ................................................ 75
Fire Protection ................................................ 77
Recreation .................................................. 78
Accessibility .............................................. 78
Crowdedness .............................................. 78
Pleasantness .............................................. 79
Education . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... . . . 79
Local Transportation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Travel times . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Congestion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
Parking convenience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
Accessibility to public transportation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Traffic hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Shopping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Accessibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Citizen satisfaction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84

V. HOUSING AND SOCIAL CONDITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85

Housing Adequacy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
Changes in substandard housing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
Changes in housing mix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
Estimating housing needs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
People Displaced . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ... 87
Population Mix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
Crowdedness . . . . . . . . . . . . . . . . . . . . . . . ... . . . . . . . . . . . . . . . . . . . . . . . 88
Sociability/ Friendliness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
Privacy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
Overall Contentment with Neighborhood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90

Appendix: Other Impact Measures Considered . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91

Financial stability of developer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Change in personal income per household . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Change in utility costs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Change in available agricultural and commercial forest land . . . . . . . . . . . . . . . . . . . 91
Change in microclimate . . . I . . . . . . . . . . . . . . . I . . . . . . . . . . . . . . . . . . . 91
Land pollution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Storm drainage quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Additional measures of changes in the quality of government services . . . . . . . . . . . . . 93
Changes in death and illness rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Level of hazard to workers and public during construction . . . . . . . . . . . . . . . . . 93
Level of structural safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Change in car trips or car miles per person per day . . . . . . . . . . . . . . . . . . . . . . 93
Consumer protection measures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Neighborhood stability -change in tenure rates . . . . . . . . . . . . . . . . . . . . . . . 93

INTRODUCTION

For each measure listed in Exhibit I of the Summary, the detailed analyses can be used to improve relatively
this section discusses the rationale, problems, and some inexpensive methods that are more suitable for the bulk of
alternative forms of the measure, where appropriate. Data development decisions.
collection procedures for evaluating past and proposed Data collection procedures for evaluating past and
development are also outlined, but it is beyond the scope of proposed developments are discussed separately where
this preliminary work to develop detailed procedures. there is a significant difference in methodology.
A major concern is to provide data collection In general, the preferred procedure for the retro-
procedures that are practical and that entail manpower and spective evaluation consists of gathering data both before
expenditure levels that local governments can afford. and after development. If data are not collected prior to
Whenever possible, procedures are suggested that utilize development, the previous conditions need to be estimated.
data and skills currently available to most local govern- The methods for doing this are often similar to those for
ments. Overemphasis on data precision can lead to unneces- making estimates forward in time and are not discussed
sary data collection costs. The precision and costs should be separately. '
commensurate with the importance of the decision at hand. Most of the discussion is worded in terms of the
Costs for many procedures remain to be determined, evaluation of a single development, but the procedures are
however. generally applicable to evaluating groups of developments
For some measures, relatively cheap but crude data as well. The numbering of the chapters and measures in Part
collection procedures are identified as well as more de- 2 correspond to Exhibit 1, pages 10 and 11.
tailed, costly procedures. The simpler procedures generally
apply to impact analyses of smaller, individual develop-
ments. The refined procedures in general would be used 1. The italic type used in this paragraph is used throughout
only for evaluating large, important, or complex develop- Part 2 to enable readers quickly to distinguish material that deals
specifically with retrospective evaluations of existing developments
ments, or groups of developments, where higher analysis (in contrast to the bulk of the discussion which is addressed to the
expenditures are justifiable. Hopefully, lessons learned from likely impacts of proposed developments).

1. ECONOMY

Development can affect the local economy in critical community chooses a level of service based in part on its
ways. Three of the most important are changes in (a) net perception of what it can afford. To further complicate
government fiscal flow (revenues less expenditures), (b) em- matters, maintaining the same expenditures per capita is
ployment, and (c) wealth.' The three are closely in- not necessarily synonymous with maintaining the same
terrelated. For example, changes in land values may quality of service, since the demands for services and the
change property tax revenues and thereby the fiscal flow. If costs of supplying them may change faster or slower than
a new development stimulates labor force migration from the rate of residental or business population growth.
other regions, the fiscal impact differs from a situation The methodology discussed here for assessing fiscal
where new employment needs are satisfied wholly from the impacts is based on the assumption that current service
local labor pool. Measures for indicating these three impacts quality, tax structure, and tax rates are to be maintained.
of development are discussed separately. The discussion focuses on evaluating proposed residential
development.
Retrospective analysis would use similar techniques
PUBLIC FISCAL BALANCE but would have much better estimates for the socio-
economic and demographic characteristics of the popula-
Measure 1. Net change in government fiscal flow. tion of the development, the public services allocated to
the development, and so forth.
A new. development's fiscal impact on local govern- Some of the major direct fiscal impacts of commer-
ment-the net change in public revenues less operating cial and industrial development are discussed, but not the
expenditures and (annualized) capital expenditures- secondary fiscal effects, such as those resulting from the
depends to a considerable extent on whether the govern- inmigration, commuting, and shopping they stimulate.
ment will maintain or change its level and quality of A detailed case study illustrating the procedures for
services to the new development and to the rest of the estimating fiscal impact has been developed by Muller and
community after the development is completed. Concur- Dawson elsewhere.2
rently, the level of service to be provided is likely to depend
to some extent on the estimated fiscal impacts. That is, the Revenue Estimates

Local revenues can be grouped into four categories:
1. Changes in wealth should preferably include both property (1) revenues associated with real property wealth-the
values and personal income. Estimating the impact of development
on either is difficult, but it seems especially difficult to estimate
changes in family income for families in the existing community 2. The Fiscal Impact of Residential and Commercial Develop-
(outside the development), other than those who will benefit ment: A Case Study, The Urban Institute, December 1972. A more
directly from new jobs in the development. We therefore discuss -detailed description of the state of the art of fiscal impact analysis
property value changes only, and consider the measures of employ- may be found in Tbomas Muller, Fiscal Impacts of Land Develop-
ment changes as at least a partial proxy for changes in family ment: Methods and Issues, The Urban Institute, to be published in
income. 1975.

largest source in most jurisdictions; (2) revenues associated revenue accruing from the proposed development to yield
with income and level of consumption, which are com- the net change in real property taxes. This is too often
prised primarily of local income, sales, and utility taxes; neglected in fiscal analysis. Likewise, if the people or
(3) per capita, per pupil, or other per "population unit" businesses displaced by the development leave the juris-
revenues, which are derived from either a per capita tax, or diction, estimates of other tax revenues lost-and expendi-
redistribution from higher levels of government; and tures reduced-may be needed.
(4) miscellaneous revenues, which include fees, user For income-producing property, such as a large
charges, fines, licenses, and minor items. apartment building, property taxes might not be based on
It is useful to identify separately the revenues from the value of the building, but rather on gross or net income.
business enterprises and revenues from households; and the This assessment approach tends to result in higher revenues
latter should be further classified as occupants of single compared to taxes on the value of the building, unless
family, townhouse, and apartment units. many units are not occupied.
Changes in property tax revenue may also result if
Revenues Related to Real Property new development induces changes in land values elsewhere
Real property is usually taxed by local governments in the community. Estimating future land values is dis-
In general, the same tax rate applies to both residential and cussed in connection with Measure 4. Although such
nonresidential property. 3 estimates are very difficult to quantify with much confi-
Property tax revenues are computed by multiplying dence, to the extent they can be approximated the
the tax rate by the assessed value of property. In most associated revenues should be accounted for.
communities, the assessed property value is a percentage of
market or full property value. For example, in California, Revenues Related to Income
assessments are based on 25 percent of market value. Thus, Revenues generated by new development may be
a $50,000 housing unit should be assessed at $12,500. In directly related to income of residents as with local income
most cases, however, there is a difference between the taxes. Or they may be indirectly related via consumption as
11 official" and actual current market value, due to a time lag with personal property taxes and local sales taxes. A
in updating assessments in an inflationary economy and to number of communities impose utility taxes related to
other factors. The true "effective tax rate," which should income insofar as higher income households have larger
be the basis for estimating additional revenue from new real housing units and more appliances, and thus consume more
property, can be computed by dividing the current market energy and water. Excise taxes on specific goods also relate
value of similar property in the community (estimated from to consumption patterns.
recent real estate sales) by tax payments from the property. To estimate these income-related taxes, it is necessary
The effective tax rate, with few exceptions, is below the to estimate the expected household income of new resi-
official rate. The average effective assessment ratio in dents, which may be derived from the relationships
California during 1971, as shown in the 1972 Census of between property value and income. These relationships, in
Government, was 20 percent of market value, not the 25 turn, can be determined from census data and consumer
percent ratio required by state legislation. Thus an official surveys.4
or nominal tax rate of $15 per $100 of assessed value, for If monthly rent payments for proposed apartment
instance, would amount to a 3 percent effective tax rate, units have been set, income estimates can be derived by
not 3.75 percent as one might assume from use of the assuming rent payments to be a specified share of income.5
official assessment ratio. The share of income allocated for housing varies somewhat
The estimated market value of land and structures is by location, age, and size of the household, and by type of
usually provided by the developer. It can be compared to housing. Annual rental payments also may be estimated as
values of similar property to determine if it reasonably representing, on the average, between one-seventh to
reflects the local market. The property tax revenues may one-ninth of the value of the housing unit.
then be estimated by multiplying the estimated market
value of the new real property by the effective tax rate, 4. For a discussion of the demand for housing as a function
deducting for exemptions such as homestead, old age-low of income, see F. deLeeuw, "The Demand for Housing: A Review of
Cross Section Evidence," The Review of Economics and Statistics,
income, or veteran status. Real property taxes from the Vol. 53, February 1971, pp. 1-10. He found that the value of the
current (before development) land use on the development new owner-occupied housing was generally between 1.7 and 2.4
site should be computed and subtracted from the estimated times annual income.
5. A number of government publications discuss these
3. There are exceptions, as in Minnesota, where industrial and proportions. For example, see U.S. Department of Labor, Three
commercial property are taxed at a higher rate than residential Standards of Living for Urban Families, Bulletin No. 1570-5,
property. Washington, D.C., 1969.

46 Data Sources and Analysis

A more direct method for estimating income of new sharing funds are reduced; an increase in relative tax effort
residents is to examine applications to mortgage institu- leads to an increase in the federal funds.) Estimates of all
tions, developers, and apartment managers. However, access per capita taxes should be based on the expected change in
to these data is extremely difficult because of con- local population or school enrollment, applying whatever
fidentiality. formulas are used for computing such taxes.
Sales and excise tax receipts can be estimated-given
data on income-from various surveys on expenditures by.
income class, household size, region, and metropolitan User Charges, Service Fees, Miscellaneous Revenues
area. 6 User charges for utility services, other revenues from
Income taxes can be estimated directly by application public utility operations, and fees for public safety,
of appropriate rates to taxable income and size of house- recreational, and other services also can provide substantial
hold. In a few states, local governments can impose a tax on revenue to local governments.8 Such user charges, fees, and
income of residents, or a tax on payrolls, based on place of fines initially should be allocated between business firms
employment. Many cities in Pennsylvania and Ohio tax and households. The revenues accruing from households
income earned in the community. In Maryland, all counties can be approximated on the basis of recent per capita
levy an income tax on residents of their jurisdiction. In some receipts from these sources by the jurisdiction.
states, these local income or payroll taxes are not permitted.
Personal property subject to taxation varies widely.
The most common items subject to this tax are automobiles Operating Expenditure Estimates
and, to a lesser extent, major household goods. Their value The importance and scope of local public services for
7
can be estimated by their relation to income. In the case which expenditures must be estimated can differ sharply
of automobiles, it is necessary to ascertain the base used for
estimating value (wholesale price, loan value, or market among and within states. For example, water and sewage
price) and the effective tax rate. Businesses sometimes must utilities and roads and highways are maintained by many
pay personal property taxes based on machinery and localities but not others. Health and welfare often are not
inventory; these can be roughly estimated if the type of city responsibilities, and tend to be small portions of some
proposed industry is known. county budgets. However, they are major expenditure items
Utility taxes are frequently levied as a percentage of in cities such as New York or Detroit and in many counties.
The allocation techniques discussed here assume that
utility bills. Estimates of average bills can be based on current local gover nment personnel (teachers, maintenance
utility company data for various types of residences, such crews) generally are fully occupied. Thus, a new develop-
as large single-family dwellings, smaller single-family dwell- ment that creates additional demand for their services
ings, and apartments. would, in the absence of additional resources, reduce the
quality of services. The allocation techniques estimate the
Per Capita Revenues cost of maintaining the existing scope and quality of
Local governments in some states administer a per services. 'Me attempt to determine average costs or addi-
capita or "head" tax on all adults. More frequently, local tional costs for each service, if they can be determined, will
government is - the recipient of state or county revenues be very useful for determining the impacts of new
distributed on the basis of the number of residents or the development. It is recognized, however, that existing
number of students. For example, profits from the alco- personnel may be underutilized because of inefficiencies,
holic beverage sales by the state are distributed to local anticipation of future demand, or other reasons, in which
jurisdictions in Virginia based on population, while sales- tax cases judgmental adjustments in operating expenditure
receipts are distributed on the basis of school-age residents. estimates would have to be made.
Federal revenue sharing for local jurisdictions, as presently Local operating expenditures can be grouped into
legislated, also uses population as one criterion. (The other those incurred in supplying services used (1) primarily by
criteria are per capita income and tax effort: as income in a households, such as education, libraries, health and wel-
community rises relative to other jurisdictions, revenue fare, and recreation, and those used (2) by both business
enterprises and households, such as fire and police, utilities.
general government, and transportation.
6. U.S. Department of Labor, Bureau of Labor Statistics,
Survey of Consumer Expenditures, Report No. 237-88. Washington,
D.C., 1965. 8. For an example of the important role such revenues may
7. For data on the relationship between automobile value and play, see T. Muller and G. Dawson, The Impact of Annexation on
personal income, see the most current issue, Bureau of the Census, City Finances: A Case Study in Richmond, Virginia, Washington,
Consumer Buying Indicators, Series P-65, Washington, D.C. D.C., The Urban Institute, 1973.

The Economy 47

Household-Related Expenditures-Education In most states the level of state aid for public
In most local jurisdictions, public education is the education is based, at least in part, on per pupil property
largest outlay, as high as 80 percent of operating expendi- values. Thus, a proposed commercial, industrial, or expen-
tures in suburban areas of states in which the state sive residential development will increase the per pupil
governments do not absorb the major share of these property base, decreasing the per pupil state contribution in
burdens. Therefore, the factor which usually determines the future.
whether a residential development will result in a fiscal Household-Related Expenditures-Noneducational Services
surplus or liability is the projected incremental expenditure
for public education. One simplistic approach to estimating additional
The two most important factors which determine noneducational expenditures associated with new house-
school enrollment and therefore education expenditures are holds is to assume that the cost per new resident will equal
the type of housing and number of bedrooms per housing the average cost of these services per existing resident. This
unit. A number of studies show how to estimate enrollment easy computation is based on the premise @that (1) demand
on the basis of these two factors.9 With few exceptions, is independent of socioeconomic and demographic charac-
detached single-family housing units, particularly those teristics, or that (2) population characteristics of new
with four or more bedrooms, and garden apartments with residents are similar to the base population. It also implies
three bedrooms, have the most school-age children per unit. that the unit cost of delivering the services remains constant
New detached housing units typically have more children while demand increases. Numerous studies suggest that
than do older units. The fewest children per unit are found these premises are questionable.'o Characteristics of inmi-
in highrise luxury apartments and condorniniums, one- grants generally differ from those of the base population."
bedroom garden apartments, and two-bedroom town- The type and unit value of housing can be used to estimate
houses. resident characteristics, especially income distribution.
In addition to housing type, racial and ethnic Some of the complexities to be taken into account
.characteristics, which are related to children per family and for improved estimates of noneducational expenditures are
reliance on parochial schools, also influence public school discussed in the sections that follow. Cost situations vary
enrollment. Income, which is related to housing type, too widely from community to community to permit a
affects both the demand for higher quality educational detailed approach here, but the various references cited will
services and the reliance on private schools and thus affects suggest guidelines for interested officials.
public school population and budget. Health and welfare. Most health and welfare services
The distribution of students among grade levels is are directly linked to income. These expenditures tend to
frequently also a function of housing type. Apartment be concentrated in older, lower-income areas of a jurisdic-
residents tend to have proportionately more children in tion. Since the income of residents in new nonsubsidized
elementary grades, and per pupil costs are up to one-third housing can be expected to be considerably above the level
lower in these grades. The use of average per student that would qualify for welfare and health services for the
expenditure throughout the school district, without refer- indigent, the demand and thus the incremental cost of
ence to these differences in grade level distribution for each social services is likely to be low.
housing type, is likely to be misleading. To assess the impact of new residents on social
Statistics on children per unit considering the various services, the proportion of new households whose income
factors just cited can be developed from school attendance or age is at a level which qualified for social services should
records for the community or similar communities, if they be estimated. In addition, the cost of health services
are not already available from the school board. The available to all residents, regardless of income, should be
estimated number of new students per grade times the computed. As population increases, it also may be assumed
average cost per student in each grade yields the total that the unit cost of social services will rise somewhat,
estimated educational expenditure. because the cost of living and wages generally are higher in
In communities which support junior colleges and larger communities than in smaller ones.
other post-high school education, the impact of new
developments on these facilities. also needs to be estimated.
Enrollment in such institutions is a function of household 10. The relationship between population size, density and
demographic characteristics and income. the unit cost of public services is discussed in Thomas Muller, Fiscal
Issues in Metropolitan Growth, Washington Metropolitan Council of
9. See, for "ample, Fiscal and Land Use Analysis of P@ince Governments, Washington, D.C., 1973.
George's County, Doxiadis Urban Systems, Washington, D.C., 1970, 11. Characteristics of inmigrants to large urban areas can be
and George Sternlieb, Housing Development and Municipal Costs, estimated from Bureau of Census Mobility of Metropolitan Areas,
New Brunswick, N.J., Rutgers University Press, 1973. PC(2)-2c, Washington, D.C., 1973.

48 Data Sources and Analysis

Recreation and libraries. The demand for certain allocation. For example, the number of fire calls associated
recreation and library facilities may increase with the with business versus the total calls could be used for
inmigration of higher income residents. Concurrently, new allocating police and fire services. The proportion of trips
developments may provide their own private facilities, generated by residences versus businesses could be used for
reducing the pressure on public services. Some communities allocating local transportation services.
plan for a fixed quantity of recreation facilities and open Some services are aimed directly at the business
space per capita regardless of private facilities. sector, such as the testing and sealing of scales. Their costs
Preferably, the additional demand for recreational should be fully allocated to business, even though some
facilities as a function of age, income, and location of benefits may accrue to the residents.
residents would be used to estimate new recreation oper- Once historical costs are allocated between business
ating expenditures, modified by special circumstances and and residences, unit costs can be computed and used for
characteristics of local policy. In the absence of such data, estimating expenditures for new development. Some fur-
or, if the policy is equal allocation per capita, the current ther comments on estimating costs of the major jointly
average cost per household should be allocated to the new used services follow.
development. General government. It is difficult to allocate most
general government services to a specific development. For
Services Utilized Jointly by Households and Businesses small developments, general expenditures can be estimated
Most local services are utilized by both households on a per capita basis.
and business enterprises. As in the case of the household- However, as the community grows, per capita expen-
related services, it is preferable to base cost estimates on ditures for general services tend to increase. A wider scope
actual service additions that can be attributed to the new of services is offered, and more highly trained and paid
professionals are hired. For large-scale developments, using
development. Where circumstances do not allow this, past per capita costs may thus underestimate the incre-
estimates may be based on past expenditures per house- mental expenditure. The actual allocation should reflect the
hold, per business employee, or per $ 1,000 property value. experience of similar communities in the state which have
As a first step for estimating these unit costs, it is been growing rapidly in comparison to those where growth
useful to identify past expenditures for each sector- has been small. This method of estimating the future cost
households and businesses.'2 in some communities, busi- of services has been applied to a number of communities.14
ness enterpnises are concentrated in areas with few
residential structures, and the services devoted to them may Fire services. The need for additional fire service
be readily identified. For example, a fire company may expenditures is determined by the accessibility of new
serve primarily a central business district, so that all or a developments to existing fire stations, the current demand
large share of that cost can be allocated to business. level at those stations, and the types of proposed structures.
In expanding areas, new commercial and perhaps The frequency of fires per housing unit in new
industrial property may be in fairly close proximity to residential developments, based on empirical data, is usually
housing, making it difficult to identify the actual resources below community averages. However, low density develop-
supplied for each. Several allocation schemes have been ment can require more fire stations per housing unit to
devised. The most commonly utilized method is to allocate offset the longer travel times when housing is spread out.
expenditures for jointly used services-particularly public And despite locational differences, certain communities
safety-to business and residences in proportion to their maintain a fixed relationship between firemen and
relative property value. An alternative is to rely on the population.'s
number of employees in business enterprises, as a propor- The suggested approach is to allocate incremental
tion of total employees and residents, for the allocation to operating outlays for fire services on the basis of additional
business." Both of these approaches, however, tend to manpower required. If no added personnel are needed, one
reflect benefit received rather than cost incurred. Where can estimate the anticipated number of additional fire calls
demand data are available, these may be used as the basis of as a proportion of the total number of calls for the fire
station nearest the development. This would indicate the

12. A frequent mistake in cost-revenue analysis is to com-
pute per capita (resident) costs by dividing total costs (for
businesses and residents) by the number of residents, rather than 14. See, for example, George Sternlieb, Housing Develop-
dividing just the resident-related part of the costs by the number of men t and Municipal Costs, op. cit.
residents. 15. In communities within Santa Clara County, for example,
13. See, W. Isard and R. Coughlin, Municipal Costs and a ratio of one fireman per 1000 residents is maintained. See
Revenue Resulting from Community Growth, Federal Reserve Bank Municipal Cost Revenue Analysis, South Santa Clara Planning
of Boston, Boston, 1957. Department, 1973.

The Economy 49

share of the fire station operating cost to be allocated to 0 Choice of the lifetime and interest rates to be
the new development. used in annualizing costs of new plant.
Police services. Per capita police outlays, once some
minimum population base is reached, increase as the size of 0 The timing of the new investment.
a city increases. It is not known to what extent this is
attributable to changes in the level and types of police Cost Allocation
service provided, socioeconomic characteristics, population Capital expenditures associated with new develop-
density, or other factors. The major factor appears to be ment can be grouped into two categories. First, facilities
the higher level of crime per capita. linked directly with the development, such as new schools,
New developments characterized in the main by low sewer lines, fire stations, and other new facilities to be
density housing are likely to have low crime yates.16 utilized primarily by the new development. Costs of these
Insofar as crime rates reflect direct demand for police facilities can be allocated largely or wholly to the new
services, the use of a crime index as a proxy for demand is development. Second, facilities constructed or expanded as
likely to show that the incremental cost in new develop- part of a capital improvement program which will be shared
ments is below the average cost of providing service. Thus
by existing as well as new residents or enteriprises in the
using average costs might seem biased. However, police jurisdiction. Such facilities could include junior colleges,
protection extends to roads, shopping, areas, and other new sewage or water treatment plants, and health care
facilities where residents shop and work. In addition, only a centers. They are generally not triggered by a single
small share of total police calls are directly linked to crimes. development, unless it is very large.
Thus average costs may not be as poor a proxy as one might The costs of the second category pose difficult,
think at first. classic allocation questions involving consideration of scale
Another approach is to base costs on the estimated economies and the optimum size and timing of new plant
additional manpower allocated to the new area, adding a construction. The approaches are widely argued and a full
proportional share of central administrative and related discussion cannot be included here. Only a few suggestions
overhead expenditures. Some communities apply a stan- must suffice.
dard, such as 1.6 uniformed police per 1,000 residents. This If a new facility is part of a capital improvement plan
implicitly assumes that demand for police services is and is initially underutilized in expectation of future
independent of new population characteristics or the growth, only the share of the total cost needed to meet the
housing mix. It also deals with the development alone, not demands created by the new development should be
reflecting its contribution to the higher per capita costs allocated to it. For example, for a school the number of
associated with larger communities. pupil-years of education required by the development as a
The preferred but somewhat more difficult approach percent of the total pupil-years provided by the school over
is to estimate the additional manpower likely to be added, its expected life could be used to allocate the annualized
based on past experience with sinlilar developments, if any, capital costs of the school to the development. This gives
and discussions with police officials, so that the latest some of the benefit from the expected economy of scale to
policies can be reflected. To the costs of manpower the new development. The balance of the annualized cost,
necessary to serve the new development would be added until the facility is fully utilized, is shared by the total
expected increases in general costs due to the community's community. However, if earlier construction of the new
increased population, based on experience in other like facility is required because of the specific development, the
communities. analysis should take account of local funds requiring earlier
Capital Expenditure Estimates outlay and the likely costs of construction at different
times, including anticipated interest costs on bonds that
Three ma or tasks are involved in estimating the costs would be borrowed by the local government for the
17
of public capital improvements associated with new devel- project.
opment. If the new development uses available space in
existing facilities, some would allocate only the short-term
0 The allocation of facility costs between the incremental cost, some the long-term incremental cost, and
existing community and the new development. some the average cost. Which to use depends on the
viewpoint and purpose of the analysis. The short-term
16. See, for example, "Cost Revenue Analysis of New
Housing Development in the City of San Diego," Growth Cost 17. In an inflationary economy, it is frequently advanta-
Revenue Studies, Associated Home Builders, Berkeley, 1973;Fiscal geous to initiate construction in anticipation of future demands,
and Land Use Analysis of Prince George's County, Doxiadis Urban since annual debt payments are Exed while the tax base is
Systems, Inc., Washington, D.C., 1970. expanding.

Data Sources and Analysis

incremental cost (which may be zero) reflects the out-of- portion of capital needs can be met from current revenues,
pocket additional expense for the facility. The long-term on a "pay as you go" basis. Capital expenditures for such
incremental cost reflects the costs attributed to new services as publicly owned utilities are usually self-financing
development over the7 long run, including economies or from user charges through revenue bonds, and thus impose
diseconornies of scale they lead to. The average cost no direct burden on the public sector fiscal structure.
concept assumes each user bears an equal burden. However, major capital costs, for services not funded by
For either case-4hether the new development uses user charges, particularly in areas of rapid growth, cannot
old or new facilities-two separate capital expenditure be financed from current funds. Therefore, general obliga-
computations might be made, one emphasizing causation of tion bonds are issued for a selected payback period.
costs, the other what the community will have to spend. The bond repayment periods selected by com-
The first would indicate the relative burden on services munities generally vary between 20 and 30 years. A
from the new development, the second the changes in fiscal suggested approach for determining per annum -cost in-
outlays that would be needed. volves calculating the straight line amortization of capital
In some cases, :a new development triggers a new over the useful life of the investment and adding. the
capital investment that will be used by all of the commu- interest on the average balance outstanding. The interest
nity, and that will raise the per capita cost to the rate selected when computing annualized capital expendi-
community for a service. An example is a tertiary sewage lures should reflect the bond market at the time of the
treatment plant required to keep water pollution below analysis. In 1973, interest rates for communities with a high
some limit. In most communities the practice is to bond rating fluctuated between 4.7 and 5.5 percent. (These
distribute the cost of such facilities equally among all users. percentages are considerably below the private market rate,
The cost for fiscal impact analysis purposes might be since the interest on these bonds is not subjected to federal
allocated to the entire community, but in some cases the income taxes.)
costs might be allocated to the new development-it An alternative approach for computing the capital
depends on the reasons for adding the plant and whether cost would be to estimate the useful economic life of the
overall service quality improves or remains the same. investment (excluding the value of the land), independent
Facilities fully utilized prior to new development, of the bond repayment period, Presumably, if the actual
such as public schools; should not be considered as part of economic life could be estimated, the annual interest
the capital cost attribu :table to the new development. charges on a bond could be added to the amortized per
annum economic life of the project. 'thus, if bonds for a
Annualizing Costs project had a 30-year repayment period, but the useful
There are three methods of paying for major capital economic life of the project was 40 years, the annual
projects: (1) general revenues from current tax receipts, (2) capital costs could be reduced, although the difference
general obligation or revenue bonds, and (3) current reve- would not be substantial. Technological and other changes
nue combined with general obligation or revenue bonds.' 8 may result in a shorter useful economic life for a capital
Whether capital expenditures, which provide current investment than initially projected. In addition, elements of
as well as future benefits, should be paid from current a particular project are likely to have differing economic
revenues or over an extended time period, involves issues of life spans. As a result, basing estimates on the anticipated
equity, since the composition of the population using the economic life of a project has practical limitations. What-
capital improvements undergoes change during the useful ever method of annualization is used should be clearly
life of the investment." Most large communities-for both stated, since it is often the basis for criticism in comparing
fiscal and political reasons-tend to borrow funds, particu- fiscal flows.
larly for school facilities.
The method of financing chosen by a jurisdiction Timing of Investment
influences the short-term and long-term costs of capital Unless existing facilities are underutilized, increases in
investment. In a slow-growing jurisdiction, a substantial population or business enterprise expansion require imme-
diate new public and private sector capital investment. The
alternative would be a reduction in the level and quality of
18. Revenue bonds are those bonds secured with income
received by a jurisdiction from the earnings of a revenue-producing existing services, such as double school sessions, increased
enterprise, such as waterworks. General obligation bonds are secured traffic congestion, or overcrowded recreational facilities.
by an unconditional pledge of a jurisdiction's credit, including its In areas of rapid growth, public infrastructure invest-
taxing power. ments frequently lag behind population increases because
19. For a theoretical discussion of public debt issues, see R.
A. Musgrave, The Theory of Public Finance, New York, McGraw of public sector fiscal limitations, such as legal limits on
HUI, 1959. borrowing; lag in revenues from new development; the

The Economy 51

initial diseconornies of scale (i.e., underutilization) associ- Industrial and Commercial Development
ated with new facilities; or because of inadequate planning. I Nonresidential development may bring three types of
As a result, there is often a short-term degradation in the employment to the community: (1) short-term jobs, related
provision of public services. If this is expected to be the to construction of the development and its associated
case, it should be reflected in the various measures (17-36) public and private infrastructure such as utility lines, roads,
of service quality. power plant extensions, and telephone switching,21 (2)
long-term direct employment provided by new or expanded
EMPLOYMENT business enterprises, and (3) secondary impacts due to in-
creased economic activity stimulated by the development.
Measure 2. Number of new long-term and short- Short-Term
term jobs provided.
Construction-related short-term employment may
Measure 3. Change in the numbers and percent offer little help to those in the community who are
employed, unemployed, and underemployed. presently underemployed or unemployed, though it may
prevent their number from increasing. The unemployed
The traditional measure of the impact of a new often do not have the necessary skill levels to participate.
development on employment is the estimated total number The number of additional short-term jobs provided to the
of jobs created. This measure is of interest and relatively community depends on the local labor market and trade
easy to estimate, but it does not directly reflect the impact union practices.
of the development on employment opportunities for the Short-term employment opportunities provided by
present citizens of the community. It does not indicate past development can be estimated from data provided by
whether the newjobs,will be taken by persons from outside organizations which participated in construction and re-
the community or by persons within the community. In the lated activities. The employment actually generated may
latter case, will old jobs be wiped out or will new openings differ from original estimates as a result of construction
be created and left for others to fill? delays, modifications of plans, changes in union contracts,
I I To deal with these matters requires explicit estimates and changes in the skill mix of workers used, not to
of the impact of the development on unemployment and mention unrealistic initial estimates. Local communities
underemployment as well as on the new long-term and should find it useful to occasionally determine the accuracy
short-term jobs added to the community. Even if the of such estimates in retrospect.
impact on unemployment and underemployment can be The likely number of short-term, construction-related
only crudely estimated, as is likely, it will help provide a jobs resulting from proposed development may be esti-
more balanced impression of the significance of the new mated from similar projects previously completed. A
jobs. Note that a net addition of jobs to a community second approach is to estimate the labor share of the total
reduces the percentage unemployed, even if no one expected construction costs, and then to convert this into
currently unemployed gets a job. For this reason, absolute man-years based on average construction labor costs. Data
as well as percentage changes should be identified. on the labor portions of total costs for various types of
Industrial and commercial development often directly construction are compiled by trade associations and govern-
create additional jobs. Residential development only creates ment agencies. A third approach is to estimate the number
jobs indirectly, except for those utilized in the construction of man-hours for plumbers, electricians, and other trades
itself.'o It is useful, therefore, to treat the employment per building unit based on past trends. The developer-who
effects of these types of development separately. probably already will have done the computation-may be a
source for these data.

20. It is generally assumed that the demand for residential Long-Term
construction (except retirement communities, tourist facilities, or
vacation homes) follows employment opportunities. It is possible Employment impacts of industrial and commercial
but rare that a shortage of housing precludes further industrial/ developments in the long run depend on the number of new
commercial development. In some cases, the availability of a wide jobs generated, the availability in the community of the
range of housing may attract industry, but this is not the typical
situation. lberefore, residential development generally does not
result in creating long-term employment in the private sector
directly. However, it may indirectly create public sector jobs for 21. 11ough called short-term, these jobs are of course often
police, firefighters, teachers, etc., and private sector jobs servicing long-term for the employee involved because of continual develop-
household needs to the extent that the development attracts new ment. But if development stopped, it is likely that these jobs would,
residents to the community. too.

[Paragraphs in italics deal with retrospective analyses]
52 Data Sources and Analysis

skills needed, and the proportion of these jobs likely to be incorporate the latest technology, and may have higher
filled by community residents, commuters, or inmigrants. It skilled labor, higher wages and less employees per unit of
further depends on whether local persons who fill the new output than the averages listed by industry in the published
jobs would otherwise be unemployed, would just be sources. In fact, relocation of a business within a juris-
entering or reentering the labor force (as in the case of diction may lead to a net loss of employment opportunities
teenagers and wives of heads of household who were not because of the substitution of capital for labor, unless
previously working or seeking work), or changing employ- relocation is accompanied by expansion of output. On the
ment within the community. In the latter case, the impact other hand, if a business is relocating from a high wage area
further depends on whether the jobs left behind are filled, to take advantage of the availability of labor, then a more
and if so, whether from within the community. Unfortu- labor-intensive job production process might be used.
nately, data on the unemployed and underemployed, Evaluating the effect of past industrial and commer-
particularly within local jurisdictions, are usually poor. cial development on long-term unemployment and under-
Data on the new long-term employment expected in employment may be undertaken with data provided by
the new development may be available directly from its employers within the project site or by a survey among new
planned businesses. Most firms estimate the number of employees there to determine their prior work location and
employees needed for their expected level of output or work status. For large developments, one might check for
service. It may be useful for the local government to detectable changes in overall community unemployment
request that proposed enterprises provide information on statistics.
the approximate number, type, and gross wage structure of Where possible, various categories of unemployment
employees they anticipate, identifying the number and status should be distinguished. For example, a housewife
types of workers to be imported (including transfers within who did not seek work until a new enterprise located
the organization) and the number and types to be hired within commuting distance for her is defined by the
locally or within commuting distance. Otherwise, the Department of Labor as moving into employment from
proportion of new jobs likely to go to people within the outside the labor force, not from the ranks of the
community as opposed to those outside but within commu- unemployed. Unemployed people may be categorized as
ting distance may be estimated based on past experience "frictionally u ne mployed "-that is, temporarily between
with similar industries. The proportion of jobs going to jobs, or having difficulty getting their first job-or as
persons outside commuting distance versus those within structural, "hard core" jobless, a more permanent and more
range is much trickier to estimate, since it is dependent on serious problem. Still others are underemployed-holding
the relative slack in the labor markets in communities that jobs below their capacity due to immobility, discrimi-
are within and outside commuting distance. nation, tight job markets, or other reasons.
Details on the number of expected jobs will not be
available when the specific enterprises that will occupy the Secondary Impacts
development are unknown, or when they are unwilling to Employment, particularly in retain business and serv-
provide this somewhat sensitive information. As an alterna- ices, may result from new development via the so-called
tive, the number and skill mix of new jobs may be roughly multiplier effect. Each new primary job created by indus-
estimated from the assumed or likely types of businesses, trial and commercial development may stimulate added
based on estimates of the floor space, or (though less service jobs. There also may be increased demand for labor
frequently available) expected payroll or sales volume. in industries supplying materials for construction or for use
Estimates of floor space per employee are available by type by the new industry, though these jobs may fall largely
of industry.22 Estimates of the wage structure of new outside the immediate community.
businesses can be based on average wage rates published by The secondary employment impacts within the com-
industry type.23 The census also provides payroll data for munity can best be estimated from data on previous
blue collar and white collar labor for metropolitan areas, expansions that show growth of service industries in
cities, and counties.24 However, new facilities tend to relation to the increase of primary jobs. Particularly in
smaller communities, a larger share of the secondary
employment may "leak out" to other areas.
22. For example, see Connecticut Development Group, Inc., Secondary employment impacts for specific past
Cost-Revenue Impact Analysis for Residential Developments, New
Haven, 1973. developments will usually be too diffuse to identify
23. U.S. Bureau of the Census. County Business Patterns, explicitly. Exceptions would be special circumstances, as
published annually, see most recent report. when the new development was large and relatively
24. U.S. Bureau of the Census, Census of Manufacturing, see isolated, leading to the creation of small service businesses
most recent five-year Census or most recent annual survey. in its immediate vicinity.

The Economy 53

Residential Development ment should be examined. The U.S. Bureau of Labor
I Estimating construction-related short-term employ- Statistics publishes detailed data.on rates of employment
ment from residential development is similar to the by industry.
procedure used for industrial and commercial develop- WEALTH
ment.25
Secondary impacts on public employment anticipated Measure 4. Change in land values.
for some services can be obtained from the government
agencies. For example, the board of education might Development may have a sharp impact on land values
estimate the additional teachers to be hired as the result of in its vicinity-either up or down, though usually up. The
a new housing development. For other public services, such degree of impact is a function of many factors, including
as police and fire, the increased personnel should probably the prospects of further development, zoning policies, the
be prorated according to population, or on whatever basis demand for land for various purposes, changes in economic
would be consistent with the allocation of costs'used for activity generated by the development, accessibility, avail-
the fiscal flow analysis (see the expenditure estimates in able amenities, and the type of land use change. The
Measure 1).
impacts on land values usually diminish with distance from
Secondary impacts on private sector employment the development.
usually cannot be estimated directly. In some cases, such as A number of studies have undertaken to quantify the
when a concentration of housing is likely to lead to the relationship of various factors to land values.27 While the
building of a shopping center or other service facilities, new major reasons for differences in land value from one area to
employment can be crudely estimated based on the another have been reasonably well established, less is
proportion of total sales to consumers from the new known about the quantitative impact of new developments
development. Alternatively, more or less standard multi- on surrounding land values, although some studies have
pliers for relating secondary to primary employment can be examined the relationship.28
used.26 One approach for estimating the impact of past
Stability development on values of nearby property is to compare
sales data for similar properties before and after the
In addition to the number' of jobs created for the development. Prices should be 'adjusted for infi!ation. A
community, it is important for a community to consider second approach is to examine property assessment records
the stability of the jobs created. Employment in some types before and after development to determine how local
of industry, such as utilities, government, and nondurable appraisers anticipated the impact of the new development
goods production, is more stable than in others, such as on surrounding property values relative to assessments for
defense or durable goods production. A community reduces similar properties that have not been affected by develop-
the risk of high unemployment by attracting a wide ment in their immediate vicinity. It should be noted also
spectrum of enterprises, including those not sensitive to that public improvements-roads, sewers, parks, etc.-may
short-term changes in the economy. The stability of a have a greater impact on property values than the new
particular enterprise in a community also depends on developments themselves, although the two are closely
factors independent of the economy as a whole-such as the related. 29
quality of management, the quality of union organization,
and the supply of workers with necessary skills. 27. See, for example, William J. Stull, "An Essay on
Stability of jobs associated with past developments Externalities, Property Values and Urban Zoning," unpublished
can be estimated, by comparing how many workers were Ph.D. dissertation, Massachusetts Institute of Technology, 1971.
Findings discussed in Cost-Revenue Impact Analysis for Residential
laid off due to cutbacks and the rate of expansion of the Developments, The Connecticut Development Group, Inc., 1973.
local labor force during the two or three years after those Also E.F. Brigham, A Model of Residential Land Values, RAND
developments were completed. Corporation RM-4043-RC, 1964; and D.M. Grether and P.
Mieszkowski, "Determinants of Real Estate Values," Journal of
To estimate the stability of the new jobs, data on the Urban Economics, Vol. 1, No. 2, May 1974, pp. 127-146.
experience of industries to be located in the new develop- 28. See, for example, Mohammed A. Qadeer, "Local Land
Market and a New Town: Columbia's Impact on Land Prices in
25. For examples of typical labor requirements, see R. Ban, Howard County, Maryland," AIP journal, March 1974,
"Labor Requirements for Construction of Single Family Houses," pp. 110-123.
Monthly Labor Review, September 1971, pp. 12-17. 29. An example of land price increases that resulted from
26. See, for example, Charles B. Garrison, "New Industry in public improvements may be found in The Socio-Economic Impact
Small Towns: 'Me Impact of Local Government," National Tax of the Capital Beltway on Northern Virginia, University of Virginia,
Journal, December 1971, pp. 493-505. 1968.

[Paragraphs in italics deal with retrospective analyses]
54 Data Sources and Analysis

Rough estimates of property value changes to be ments is limited relative to demand, its value will rise
expected in the vicinity of a proposed development can be sharply as the artifically restricted supply is used up.
made by analogy to past experience with similar develop- However, if ample land is available, and rezoning is easy to
ments. Undoubtedly, precise estimates of future property obtain, its value will not increase as much as a result of
value changes are well beyond the state of the art for most development, since its owners already would be pricing it
situations in most communities. Nevertheless, an attempt according to the market for its potentially more intensive
should be made to at least identify areas likely to increase use.30
or decrease in value, and the likely degree of change, so as
to help identify those clientele groups that are likely to Additional factors which can influence land values in
benefit or lose from the development. Property values areas of growth include the following: availability of public
estimates also are needed for cost-revenue analysis, to facilities, property taxes, and the physical characteristics of
estimate changes in property tax revenues. the land.

Factors associated with new development which Availability of Public Facilities
directly affect land values include the following: type of Underutilized facilities such as schools, roads, fire
development, number of new households, and remaining stations, and utilities (particularly sewage treatment plants)
land available for more intensive uses. influence nearby land values by making further develop-
Type of New Development ment more immediately feasible.
The addition of detached housing units in an area Property Taxes
where single-family housing already predominates may High property taxes tend to lower land prices and to
increase property values. This is what tends to happen when discourage the long-term holding of sites that are not being
a type of development occurs that reinforces people's used in accord with their full potential. If a new develop-
expectations. If the same low-density residential area ment requires public services that cost more than the new
witnesses the construction of some highrise apartments or tax revenues it generates and necessitates a general increase
industrial facilities, a mixed impact on property values may in the community's property tax rate, this will reduce the
result. To homeowners who are concerned about increased net return on most properties and reduce their selling price.
congestion, pollution, or other possible problems, the area Low property taxes, on the other hand, make it less costly
may suddenly appear less attractive, and their decision to
sell out and move may cause the prices of their homes to for owners to hold land idle, tending to reduce the effective
drop. At the same time, land values in the area may rise supply and to raise the cost of land available for develop-
because of the anticipation among investors that additional ment.
intensive development of apartments or industry is likely to Physical Characteristics of Land
follow.
Land with desirable physical characteristics 'appre-
Number of Households in the Development ciates faster than land with neutral or negative features
New development with a large number and concentra- because it is cheaper or faster to develop or is environ-
tion of households will increase the pressure to use nearby mentally more appealing. For example, nearby residential
land for commercial uses, such as shopping centers, banks, development is likely to cause wooded land to appreciate
and gasoline stations, boosting the value of the land. faster than land without trees. Steeply sloped or very rocky
land appreciates more slowly than average-unless the view
compensates for the construction disadvantages. Where
Remaining Land Available for Development sewers are not available, the percolation capacity of the soil
The price of land in areas of rapid growth usually may influence its rate of increase.
increases as the amount of land zoned and available for 30. For a further discussion of the issue, see M. Neutze, The
development, particularly for intensive development, dimin- Suburban Apartment Boom, Baltimore, Johns Hopkins University
ishes. For example, if land zoned for high density apart- Press, 1968.

The Economy 55

11, NATURAL ENVIRONMENT

The general intent of this report is to focus on From dust and wind erosion of soil caused by
how development affects the citizenry rather than on construction or by changes in the amount of
intermediate indicators. Environmental factors, however, land cover.
are treated directly for two main reasons, even though they
are intermediate indicators of some impacts. First, they are Industrial and commercial developments have these
important in their own right as the nation is recognizing same pollution modes, plus the by-products of industrial
that the condition of the earth is an essential part of the processes that are vented to the air. Both types of
human heritage to be passed on. Second, while it becomes developments also may increase pollution indirectly by
.,increasingly evident that changes in the natural environ- stimulating activity in the community generally.
ment may strongly affect the health, economics, aesthetics, The net change in levels and distribution of pollution
and leisure opportunities of a community, it is not clear caused by the development will depend on the net number
how to translate these specific development impacts on the of inrrdgrants attracted; changes in the relative location of
environment with any degree of certainty. residential, work and shopping sites (and thereby the
amount and distribution of traffic); the displacement or
AIR POLLUTION elimination of pollution caused by the previous land use;
the location relative to local winds and other climatic
Measure 5. Change in the level of air pollutants conditions; and whether the development represents an
and change in the number of people at risk or addition or just a shift of activities within the community.'
bothered by air pollution. Three aspects of air pollution associated with devel-
opments should be estimated:
Residential developments affect air pollution through
several types of emissions: 0 The change in levels of air pollutants considered
hazardous to health or damaging to property
� From internal combustion engines, as a result (including carbon monoxide, sulfur oxides,
of changing the number, length,' distribution, hydrocarbons, particulates, nitrogen oxides,
and mode of trips. photochemical oxidants).
� From fuel burning within the development for 0 The effect on visual aesthetics, in terms of
heating and cooling. opacity and shade of emitted smoke plumes

� From power plants that serve the development. 1. To illustrate the last point, moving a factory to better
quarters across the street from where it was might have little impact
� From solid waste disposal plants that serve the on air quality in its neighborhood. The result depends on whether it
expanded production, changed processes, what it replaced at the
development. new location, and what filled in behind it at the old location.

(the blacker and denser the smoke, the more changes in emission controls, power usage, vehicle usage,
offensive it is to most people). and other factors in the rest of the community. It will be
necessary, therefore, to allocate the measured changes
0 The intensity of unpleasant odors. between the development in question and outside causes,
except perhaps for developments that are very large relative
For the changes in air pollutants, the increased to their community, or for pollutants introduced by the
number of people affected should also be estimated, development that are new to the community and easily
preferably in terms of their frequency and duration of recognized as such.
2
exposure to pollution above specified levels. These levels Where an allocation of measured changes in pollution
may be local, state, or national standards representing best between the development and other factors is necessary, it
estimates of the different levels that may impact health or may be based on estimates of the onsite and offsite
aesthetics. For example, New York City has defined an air pollutants generated by the development relative to the
quality index which categorizes pollutant levels as "good, pollutants generated from other sources. These estimates of
acceptable, unsatisfactory, or unhealthy." 3 relative proportions may range from very crude guesses at
For most small developments the analysis should one extreme to estimates based on measured emissions
probably center on changes in the immediate vicinity since from point sources, counts of vehicles, and the use of
the small increment of pollutants is not likely to be pollutant dispersion models (such as discussed below for
detectable elsewhere. Nevertheless, the cumulative effects estimating effects from proposed developments). I
of development require attention; small increments that Where physical measurements of changes in air
could be dismissed as insignificant when viewed individually quality are not feasible, estimating procedures would again
may, as a whole, substantially change overall air quality. be similar to those for proposed developments. This is
The collection of data about the impact of previous likely to be the case even in communities with mobile
development on air quality is often facilitated by the fact measuring stations since an adequate number of direct
that many cities regularly monitor air pollutants at a few measurements for estimating pollution contours will usually
sampling points. These measurements may suffice for mak- be too expensive and time consuming for a single develop-
ing gross estimates of the effects of development on air ment.
quality. But the sampling stations are unlikely to be in the If pollution contour maps are developed either by
"right" places for identifying localized effects of specific physical measurements or dispersion models or a combina-
developments. And there probably will not be enough tion of both, they may then be overlayed on residential
sampling stations to allow direct construction of pollution density maps to estimate the number of residents exposed
contour maps which are useful for estimating the number to unsatisfactory levels more than some chosen number of
4
of persons affected. times per year. The average number of people travelling
Mobile monitoring stations can be used to fill some of through high pollutant areas on each day of the week
the gaps. They can be placed at suspected "worst " spots,,in should be considered in addition to residents of those areas
the immediate vicinity of the development, at locations in determining the number of people affected. At present,
likely to reflect the hazard faced by the largest number of it will probably not be possible to produce meaningful
people, or at locations most important for extrapolat- contour maps for more than a few pollutants such as
ing pollution contours. Care must be taken in choosing carbon monoxide, though much research attention is being
the location, height, time of day, weather condition, etc., devoted to improving methodologies for other pollutants.
to help ensure that the measurements will be meaningful. Much air quality testing is already required by local,
Physically measured changes in air quality are likely state, or federal codes. Data on acceptable pollution ranges
to. result from a combination of development effects of from different sources are now available from environ-
mental protection agencies. Methods for physical sampling
and analysis of air pollutants are generally well known and
2. There are stilt major questions as to what pollution levels 6
constitute hazards, especially in the long run. Therefore, whenever are not discussed further here.
the number of people at risk is estimated, the criteria used in
defining various risks levels should be specified, too. 5. Note that emissions measured at the source-at the
3. Each of the four New York City air quality levels is smokestack, for example-are not the same as measurements of air
defined in terms of an allowable range for each of six pollutants, as quality taken at various other community locations.
described in "Air Pollution Control News," The American City,
August 1972,p. 22. 6. For general reference documents, see J. Juda, et al.
Methodology of Atmospheric Air Pollution Measurement L, Na-
4. Pollution contour maps consist of lines of equal pollutant tional Science Foundation, Washington, D.C., 1971 and R.A.
levels. They are analogous to weather maps which show lines of McCormick, Air Pollution Measurement, Environmental Protection
equal air pressure. Agency, Division of Meteorology, 1972.

[Paragraphs in italics deal with retrospective analyses]
58 Data Sources and Analysis

The shade and opacity of smoke emitted from For determining the change in vehicular emissions in
developments can be quickly determined by a trained the entire community, and not just in the vicinity of the
inspector making comparisons with a Ringelmann Chart, development, assumptions must be made about the net
which is simply a set of illustrations of different densities. 7 number of car trips and their distribution within the
The intensity of odors can most simply be deter- community. For example, if some deteriorated houses were
mined by a "trained nose " using a zero-to-four scale, such demolished to make way for'open space, and the residents
as follows: 8 were relocated across town, there might be a shift in
O-No sensation of odor. distribution of pollution but little change in gross overall
average pollution, or in the number of people affected.
I-Just detectable odor (the threshold Note that the emissions per pound of fuel are
dilution). changing annually as the proportion of cars without
2-Distinct and definite odor whose unpleasant pollution controls 9are reduced to conform with stiffer
characteristics are revealed or foreshadowed emission standards.
(the recognition threshold). Onsite Residential Heating and Cooling Systems
3-Odor strong enough to cause a person to
attempt to avoid it completely. Emissions from onsite systems can be computed from
4-Odor so strong as to be overpowering and the pounds of gas or oil consumed per day (by season),
intolerable for any length of time. times the emissions per pound given, off in the use of these
fuels. 10
Estimating changes in air quality from proposed
developments can be broken into sevetal steps: (1) esti- Solid Waste Incineration
mating additional or reduced emissions caused by the
development, (2) translating these emissions into estimates Emissions from incineration can be estimated based
of air quality,. and (3) computing the changes in the number on the pounds of refuse generated per day. This in turn can
of people likely to be exposed to air pollution levels be estimated from rules of thumb about pounds per person
considered unsafe or unpleasant. and the expected emissions per pound, or from the type
and size of the establishment in the case of business. Data
are available on the pounds of contaminants added to the
Estimating Emissions air per ton of refuse burned." Adjustments must be made
The emissions caused by the development can be for control devices and processes used.
estimated from the net change in the number of polluting
sources, and the pollutants emitted per pound of material Electrical Power
consumed per hour. The estimated emission rates must be Increased emissions from this source can be estimated
modified according to the type of pollution control devices according to the average daily power requirements and the
likely to be used, for example, in commercial heating plants fuel used to generate electricity locally.12
or factory production processes. Emissions associated with
the previous use of the site also should be estimated or
measured to assess the net effect of the new development, 9. Auto emission prediction is discussed in detail in: Jacob-
which in some cases might be a reduction in pollution. sen, Willis E., Automotive Emissions, McLean, Va., MTR-6009,
Vol. 2, Mitre Corporation, 1971, and Ott, Wayne, John F. Clarke,
Vehicular Traffic and Guntis Ozolins, Calculating Future Carbon Monoxide Emissions
and Concentrations from Urban Traffic Data, U.S. Department of
Vehicular emissions are a function of the number of Health, Education, and Welfare, National Air Pollution Control
vehicle trips per hour, average vehicle speed, and the trip Administration, Durham, North Car 'olina, 1967.
length. Thus, increased traffic congestion -which may 10. As an example of the types of data available on emissions
reduce average speeds-as well as the increased car trips per pound, see American Public Health Association, Inc., Guide to
generated by the development need to be considered. the Appraisal and Control of Air -Pollution, New York, 1969, p. 65.
11. Ibid., contains a table of contaminants per ton burned,
but note that the numbers vary, for various disposal processes and
7. Kudlich, R., Ringelmann Smoke Chart, Information Circu- pollution controls.
lar 7718., U.S. Department of Interior, Bureau of Mines, revised by
C.R. Burdick, 1955. 12. U.S. Environmental Protection Agency, Guide for Com-
piling a Comprehensive Emission Inventory. (PB212-231, APTD-
8. J. De Chiara and L. Koppelman, Planning Design Criteria, 113S), Washington, D.C., 1972, and William Vatavuk, Control
New York, Van Nostrand Reinhold, 1969, p. 336. Devices Workbook, OPA (APTD- I SO 10), 1974.

Natural Environment 59

Industry a good deal of controversy as to the accuracy of these
Industrial emissions can be estimated according to models. Research to improve and validate them is underway
projected production, based on analyses that already exist in many organizations.
for the emissions from most industrial processes.13 If
possible, smoke or odors. likely to be present should be Estimating the Number of People Affected
noted, based on past experience with similar industrial Changes in air quality should be translated into terms
processes. of changes in the number of people likely to be exposed to
Estimating Air Quality Changes pollution levels considered unsafe or uncomfortable. Pollu-
tion contour maps, described in connection with past
Gross approximations of general air quality effects developments, may be overlaid on population maps to aid
can be estimated from emission data by assuming a linear in estimating the number of residents living in areas with
relationship between increases in emissions and the result- high pollution levels. Estimates preferably should include
ant changes in ambient air quality levels. Thus, if the ratio the number of people who travel through and work in areas
of current emissions to current ambient levels is deter- of high pollution.
-niined, it may be assumed the same ratio will hold for Data from air diffusion models, cited earlier, can be
the future. This rough level of analysis is likely to be used to prepare pollution contour maps. When such models
appropriate for small developments assessed one at a time. are not appropriate, as in the case of smaller developments,
Emphasis would tend to be on the area near the develop- an attempt should still be made to estimate how many
ment, though local 'meteorological conditions must be people will be affected by changes in air quality.
considered for determining the appropriateness of this The scientific community, it has been noted, is not in
simple choice. full agreement as to what constitutes danger levels of
To predict more accurately the effect of additional various pollutants. Air quality danger thresholds, therefore,
air pollution sources on air quality, diffusion models may should be updated as new, improved information becomes
be needed. These incorporate data on location, type, and available.
amount of emissions; meterological. conditions; and in some
cases, topographical or surface conditions. For some types
of pollutants they must also consider physical and chemical WATER POLLUTION
changes as the pollutants interact with the atmosphere and
sunlight. The Environmental Protection Agency has devel- Measure 6. Change in the level of water pollutants,
oped or modified six diffusion models for emissions from change in tolerable types of use, and number of
point sources, area sources (i.e., all emissions averaged over persons affected, for each body of water.
an area), and line sources (e.g., highways).14 There remains
13. Ibid. Also, for emissions from various industrial proces- Developments may add to the pollution of bodies of
ses, R.L. Duprey, Compilation of Air Pollutant Emission Factors, water in many ways. The amounts and nature of wastes
US. Department of Health, Education and Welfare, PHC Publica- may overwhelm local sewage treatment facilities. Where
tion No. 999-AP-42, Durham, North Carolina, 1968. septic tanks are used, the wastes generated may exceed the
14. Computer programs for these models are now available
for a nominal charge. For information, write Ronald E. Ruff, capability of the soil to remove or degrade wastes, and
Meteorology Lab, EPA Environmental Research Center, Research affect underground and surface waters. Changes in land
Triangle Park, Raleigh, North Carolina. contours, vegetation, and permeable land cover during and
'Me APRAC-IA Urban Diffusion Model Computer Program
developed at Stanford Research Institute is one of these models. It after construction may increase the amount and content of
:estimates carbon monoxide concentrations in an urban area based storm runoff.
on two types of input variables: estimated traffic volumes (ex- Water pollution components to be measured for a
pressed in vehicles per hour) on a network of road segments in
the area and environs; and local meteorological conditions, body of water include suspended and dissolved solids,
largely obtainable from a local airport. The program computes dissolved oxygen, toxic materials, and the physicial charac-
average hourly pollutants for 600 points that can be positioned at teristics such as color, odor, turbidity, and temperature.
the user's discretion. This program has been validated.for San Jose These have been widely discussed and do not require
and St. Louis, with relatively good correlations between predicted
and actual levels of pollution. For a description, "An Urban elaboration here. However, as with air pollution, it is
Diffusion Simulation Model for Carbon Monoxide," Journal of the strongly recommended that changes in water pollution be
Air Pollution Control Association, Vol. 23, No. 6, June 1973, translated into terms that make the impact on the
pp. 490498. R.L. Mancuso and F.L. Ludwig, User's Manual for the
APRAC-1A Urban Diffusion Model Computer Program, Stanford community more readily understandable, and not left in
Research Institute, Menlo Park, California, 1972. Among its main technical physical or chemical terms such as "parts per
virtues are the low cost of running the model, the use of usually million." For example, each local body of water might be
available inputs, and the ability to connect the output to a contour
plotting routine that will draw isopleths. assessed in the following terms:

60 Data Sources and Analysis

� Changes in the highest safe uses. Are there source except in special circumstances. Short-term, con-
former uses which the body of water can no struction-related effects can be estimated qualitatively
longer serve? For example, is the river, lake or based on onsite inspections by local government inspectors
stream no longer safe for drinking? swimiriing? or others duping construction. Long-term effects on water
eating its fish? water skiing? boating? any of quality are much more difficult to estimate and methods
these?15 Are there uses that have become safe are still in the research stage.
as a result of development, perhaps due to new Pollution levels, once measured or estimated, can
public or private pollution controls? then be translated into the "highest safe use, " and
"aesthetically tolerable uses" by comparing the estimated
� Change in aesthetically tolerable uses. Although pollutant levels against the latest standards for safe and
still safe, a body of water may become un- tolerable levels. 17
pleasant for various recreational activities after The number of people affected by changes in water
development. On the other hand, development pollution can be estimated from citizen surveys indicating
may enhance use. Any changes in acceptable intensities of usage for various bodies of water, or by direct
uses would be noted. For example, does the onsite observation.
water look or smell bad enough to deter
swimmers? boaters? fishermen? sightseers along Data Collection for Proposed Development
the bank? 16
The basic steps are similar to those for air pollution:
� Ecological changes. Changes in pollution and estimation of net changes in effluents to each body of
physical characteristics of the water may affect water likely to be affected; computation of the dispersion
water life directly or through changes in the and interaction of the new pollutants with the existing
food chain. Changes in the food chain and in conditions; and estimation of the number of people likely
the quantity and quality of fish, shellfish, and to be affected.
water animals would be reported. This might Total gallons of sewage per day for residential and
also be included as part of Measures 9 and 10, commercial development can be estimated from the size of
which describe changes in wildlife. the residence or expected establishments and known
averages of sewage generated per person (or type and size of
Data Collection for Past Development establishment) per day."' Based on current and planned
sewage treatment capacities and efficiencies, estimates can
Data on changes in water quality are sometimes be made of whether the added sewage will or will not cause
obtainable from governmental agencies which regularly further water pollution.
monitor water pollution by components. Changes in pollu- Given the location and amount of expected effluents,
tion caused by overloading treatment facilities or new models for the various types of bodies of water can convert
treatment processes are directly measurable. The extent to these data into estimates of pollution over space and time.
which the additional pollution comes from the develop- Simple and inexpensive general in -odels do exist but are
ment, as opposed to being caused by increased sewage limited to only a few parameters, such as dissolved
volume communitywide, can be estimated from data on oxygen.19 Models which treat complex phenomena such as
water usage per year per residence and business. These data nutrient cycles are usually calibrated to a specific body of
are usually available from local water and sewer depart- water.
ments. Effluents from industrial development can be and For a given body of water, the number of people
often are monitored directly by local or higher authorities. likely to be affected can be approximated by the number of
Changes in water pollution from runoffs during and predevelopment users for each activity that will be curtailed
after construction are difficult to attribute to a particular or made less pleasant by a change in water quality.

15. For one detailed set of water safety criteria see, J.E.
McKee and H.W. Wolf, Eds., Water Quality Criteria, Second Edition, 17. As in the case of air pollution, there is considerable
Publication 3-A, ne Resources Agency of California, State Water controversy over what are pern-dssible levels for 'each water
Quality Control Board, 1963. Again the reader is cautioned that pollutant.
standards are continually changing and a subject of much contro-
versy. 18. For some representative figures of sewage generated, see
S. Grava, Urban Planning Aspects of Water Pollution Control, New
16. For a discussion of pollution levels that seem to deter York and London, Columbia University Press, 1969, pp. 177-178.
most people from various water-related recreational activities, see
D.W. Bishop and R. Aukermiann, Water Quality Criteria for Selected 19. Hydroscience, Inc., "Simplified Mathematical Modeling
Recreational Uses, Research Report No. 33, University of Illinois of Water Quality," Washington, D.C., Environmental Protection
Water Resources Center, 1970. Agency, 1971.

[Paragraphs in italics deal with retrospective analyses]
Natural Environment 61

NOISE POLLUTION drawn sample of people in the community to determine
their perceptions of changes in noise levels.
Measure 7. Change in noise and vibration levels, ne first approach, which can be used for estimating
and the number of people bothered by excessive the impacts of transportation-related noise from proposed
noise and vibration. as well as past developments, is based on the HUD Noise
Assessment Guidelines. 23 It does not require actually
Developments may affect noise levels in the short measuring the noise but rather allows one to look up the
term by construction, and in the long term by changes in expected noise levels on charts, given (a) the "effective
vehicular and pedestrian traffic, industrial processes, and distance" from the test point of interest to nearby roads,
other activities. (b) the peak hourly automobile flow and (c) the peak
Since noise increases will be most pronounced in the hourly truck flow. The "effective distance" depends on the
immediate vicinity of the development, measurement actual distance, the road gradient, the mean traffic speed,
efforts should concentrate there. Usually the areawide and the nature of sound barriers between the test point and
effects will be diffuse, though in some circumstances they the road. Four levels of noise acceptability are shown on
may be sharp enough to measure, as when a new shopping the charts representing approximations to HUD noise
center draws so much traffic that noise levels rise all along criteria for the suitability of potential sites for new
corridors leading to it. residential developments. However, although not developed
Individual developments rarely affect aircraft or for the purpose, they can also be used to estimate the
railway noise in the short run,20 though they can in the nui .sance of increased traffic to existing developments- the
aggregate by stimulating increased population or business
activity. However, present and potential aircraft and rail. need here. Procedures for estimating railway and aircraft
way noise must be considered along with traffic and other noise are also given.
noise in evaluating the suitability of a development for a I 77ie second approach, physical measurement, involves
site-especially for residential developments-in order to the collection of data using a standard A -weighted sound-
protect the future citizens and the community purse. A few level meter. 24 Raw data from this meter have been found to
years ago, the City of Los Angeles was required by the correlate quite well with human subjective responses-
courts to purchase an entire residential area from the although not as well as some of the more sophisticated
owners because noise from the nearby airport had become noise indexes. 25
overwhelming. For possibly better correlations between physical
measurements and human perceptions, sound meter data
Data Collection for Past Development can be used to compute the Traffic Noise Index of Griffiths
and Langdon26 or the Noise Pollution Level developed by
774ere are three basic approaches to assessing noise D. W. Robinson in 1969.27
levels changes in the community: (1) Using simple, graphic
noise assessment procedures such as those developed by the Technical Background, prepared for the Department of Housing and
Department of Housing and Urban Development.21 (2) Urban Development by Bolt, Beranek and Newman, Washington,
Conducting physical measurements with a standard sound- D.C., Government Printing Office, 1972; and Department of
Housing and Urban Development, Noise Abatement and Control:
level meter in the vicinity of the development site before Department Policy, Implementation Responsibilities and Standards;
and after development.22 (3) Surveying a scientifically Circular No. 1309, 1971.
23. T.J. Schultz and N.M. McMahon, Noise Assessment
20. There are exceptions. For example, the introduction or Guidelines, op. cit.
expansion of a major dynamic enterprise to a small city can result in 24. People perceive different frequencies of sound and
major changes in air traffic in a relatively short time. different sound pressure levels as different in loudness. "A-weight-
ing" is a scheme that tries to reflect this by modifying the frequency.
21. See T.J. Schultz and N.M. McMahon, Noise Assessment response of a sound-level meter so that very low and very high
Guidelines, prepared for the U.S. Department of Housing and Urban frequency sounds count less toward loudness than midrange sounds.
Development by Bolt, Beranek and Newman, Washington, D.C., 25. Theodore J. Schultz, Noise Assessment Guidelines-
Government Printing Office, 1972. The guidelines may have to be Technical Background, op. cit. (in footnote 22 above). 'Ibis refer-
adjusted to represent varying sensitivities from community to ence also presents an excellent discussion and comparison of the
community. various refined noise measures developed to date.
22. The absolute levels or computed indexes from them can
be compared with criteria set by the Environmental Protection 26. I.D. Griffiths and F.J. Langdon, "Subjective Responses
Agency, the Department of Housing and Urban Development, the to Road Traffic Noise," Journal of Sound Vibrations, Vol. 8,
Department of labor, or others. As with air and water pollution, January 1968.
the effects of particular noise levels on human health and happiness 27. Edward A. Starr, "Measuring Noise Pollution,"
is still unclear. For discussions of current standards, see for example, Spectrum, The Institute of Electrical and Electronics Engineers,
W.J. Galloway, W.E. Clark and J. Kerrick, Highway Noise Simu- Inc., Vol. 9, No. 6, June 1972, pp. 18-25. This article is an excellent
lation and Mixed J@eaction, Highway Research Board, Program summary of the problems and alternatives in measuring noise
Report No. 78, 1969; T.J. Schultz, Noise Assessment Guidelines- pollution.

[Paragraphs in italics deal with retrospective analyses]
62 Data Sources and Analysis

77te Community Noise Exposure Level, which is part technology may, make such projections misleading if ex-
of California state codes regulating airports, can be used to tended too far.
rate the effects of noise from aircraft. It is a weighted sum The impact caused by the proposed development on
of the hourly energy average of A-weighted sound levels. the existing community can be estimated in several ways:
Different weightings are used for day, night, and evening.
For each of the above noise indexes, measurements 0 Use the HUD Noise Assessment Guidelines
should be made at various times of day and days of week at discussed above. Estimated changes in traffic on
locations most likely to have increased noise and at points nearby streets and changes in nearby noise
that are most representative of the nwjority of people in barriers can be used as input to the Guidelines
the vicinity. Measurements should be made before develop- to forecast whether the development would put
ment starts, during construction, and after construction certain neighborhoods or locations into worse
until activity in the development levels off Several control categories of noise acceptability than before.
points in the general neighborhood or similar neighbor-
hoods should be measured before and after development to 0 Use analogous situations-similar developments
get some indication of how noise levels would have changed built within the community or in comparable
without the development. Care must be taken in choosing communities-to assess the likely change in
positions for making measurements with response to wind noise levels. This is a crude approach but may
patterns, surrounding buildings, vegetation and so forth. give reasonably accurate guidance if several
It wvuld be desirable to collect sufficient data to examples corresponding closely to the proposed
prepare equal-noise-level contour maps that could be development are examined.
overlaid on population maps of the community. The
number of people to be affected by a change in noise could 0 Perform a detailed analysis of expected noise
then be computed. and vibration sources (such as machinery) on
Vibration measurements need not be made except in the site, and traffic increases on or near the site.
unusual circumstances. They are relatively expensive to do Noise from each type of source would be
well and add little to simpler noise measurement. An estimated as a function of time, and combined
exception might be for a development where significantly into a composite noise-generating profile. Ex-
increased truck and bus traffic passes close to existing pected noise levels at various points in the
structures that may be damaged by the vibrations over the community could then be estimated, consider-
long run, or in which people are relatively sound-proofed ing sound barriers and meterological conditions.
but still are literally shaken. Unusual vibrations during Such an expensive, time-consuming approach is
construction process should likewise be considered. not usually necessary.
7'he third approach to assessing the impact of
development on noise levels is through the use of citizen For proposed residential development and most
surveys. Noise annoyance levels may vary considerably commercial developments, where traffic is likely to be the
despite similar mechanical measurements of noise levels. most objectionable source of noise, the first method seems
Children yelling, buses, and music, for example, could all best. The third method will serve for sites where noise from
yield a similar sound meter reading but people might rate machinery dominates and where residential or commercial
their annoyance quite differently. Because of this, surveys uses are nearby. Where the first approach is too limited and
to determine the percent of people who are significantly the third too costly or complex, the second method may be
annoyed or threatened by noise and vibrations added by used to get rough approximations. The second method also
the development are suggested. Allowance should be made will serve as a good, common sense double-check on the
for noise perceptions biased by individual attitudes toward others. Vibration estimates will only have to be made in
the development. exceptional situations, and will require special analysis.

Data Collection for Proposed Development GREENERY AND OPEN SPACE

Noise from the existing community may have an Measure 8. Amount and percent change in
impact on the proposed development and this can be greenery and open space.
evaluated using actual measurements or the H`UD Noise
Assessment Guidelines discussed above. Rough estimates of The amount of greenery and open space in a
increases in road, railway, and air traffic for at least several community is often directly changed by development.
years should be considered, but changing transportation Greenery has significant economic, social, psychological,

Natural Environment 63

and aesthetic benefits: It can reduce pollution; save energy adjunct to the measures in describing changes in greenery
(via shade and wind screening); increase privacy; improve and open space.
the climate in its immediate vicinity; and make life more
pleasant. Open space affects aesthetics, recreation oppor- WILDLIFE AND VEGETATION
tunity and the microclimate, and perceptions of crowded-
ness. Many urban areas are trying to increase their amount Measure 9. Number and types of rare or endan-
of greene ry and open space, or at least minimize losses. gered species that will be threatened.
There is concern both for large, park-size tracts and for easy Measure 10. Change in the abundance and diver-
public access to smaller parks., Expanding suburbs are trying sity of wildlife and vegetation in the development
to preserve open space commensurate with expected and community.
growth.
At a mi .nimum, estimates should be made of the Development may physically destroy vegetation and
change; in contiguous forested areas and green but un-
I harm wildlife by altering or destroying habitats. The effects
forested areas.* Land with over 50 percent tree cover is may be both on the site itself as a result of construction,
considered forested. Other measurements might include the and in the surroundings as a result of pollution from the
percent and absolute change in greenery and usable open development and secondary effects in the community.
space on the development site@` and the absolute change in The problem of rare species is not likely to be faced
open space in community (by whether private or public).19 in most individual developments. But localized destruction
Greenery and open space are measured by area (square feet of common species may significantly affect the quality of
or acres, as appropriate) as viewed from above. For some life in and near a development, and should not be ignored.
situations communities might also note changes in the Diversity of species is also thought to be an indicator of the
quality as well as the quantity of greenery. stability (and thus the health) of the ecosystem.
These measures do not always adequately reflect the 7he impact of past development on wildlife and
impact where the potential change in greenery and open vegetation my be evaluated by site surveys before and
space is small, as in a case where mature trees lining a road after development to determine the diversity and abun-
may be cut, or where a row of trees are to be added. An dance of major species at various times of the year. These
appropriate alternative measure for these cases is the surveys preferably should be made by professional zoolo-
number of trees or plants to be lost or pined. gists, botanists, ecologists or other experts. Simple logs kept
Greenery and open space on the site before develop- by onsite residents of numbers and species of wildlife
ment can be quickly mapped if not already done so by the observed might also be useM For inventorying plant
developer or it can be determined from available aerial diversity, the populations within species, numbers of
photos of the site. The U.S. Department of Agriculture's different species and their interspersion and spread over
Soil Conservation Service, the Interior Department's Geo- space should be noted. Changes in the abundance of
logical Survey, and the National Aeronautic and Space nuz.sance species of wildlife and vegetation merit special
Administration have aerial photos for many communities at attention. For major developments or series of develop-
various scales, dates, and color spectra. Local communities ment .s, surveys ranging farther afield into neighboring lands
often have their own photos, as do developers, at least for and waters should be made to determine effects of
the areas of their proposed developments. Greenery and pollution and loss of habitats.
open space planned for the development can be obtained When estimating the impact of proposed develop-
from the site plan. Presenting photos and sketches of the ment, the principal data collection technique could again be
scenery before and after development will often be a useful an inventory of existing wildlife and vegetation on the site
to learn what may be endangered.
*Bold type emphasizes alternative impact measures that may In the absence of an inventory, an analysis of habitat
be used instead of, or in addition to, the numbered measures from characteristics would provide a basis from which to make
Exhibit I which appear before each section. inferences. General characteristics to note include the
28. This includes greenery in front of buildings, in yards, and number and types of plant communities (groups of plants
on roofs. Usable open space here is that unoccupied by streets,
driveways, or parking space-it excludes balconies and includes usually found together), the linear amount of "edge" (such
unobstructed roof space that is safe and intended for recreational as the boundaries between woods and grasslands), the
use. Even if these are small quantities they may be worth presence of water, and the presence of movement corridors
"measuring" to encourage attention to them. between habitat areas. However, unless the site contains
29. This indicates the amount of space left, and is an one of the few last habitats in the region for some species,
indicator of the physical "openness" of the community-the
opposite of "built-upness." it may be difficult to predict how the development will

[Paragraphs in italics deal with retrospective analyses]
64 Data Sources and Analysis

affect the abundance of life forms in the area without If shortages get severe enough, it might be necessary
special scientific studies. Effects of pollution on wildlife to estimate their effects on health, such as the expected
and vegetation also require special studies or analogies changes in sickness or death rates due to insufficient
drawn from past examples. heating.
As a surrogate measure where special studies are not Energy shortages may also significantly affect em-
feasible, the percent of the local habitat that would be ployment, transportation, access to recreation, pollution,
destroyed or adversely affected by the development can be and so forth, and impact measures in these areas should
stated for major species found in the survey. take account of major changes in resource consumption.
Many local communities cannot afford to retain the In most cases, the direct, primary influences of a
services of a trained scientist to collect data on wildlife and development, as in providing jobs, will overshadow the
vegetation. Creation of advisory conservation communities, indirect, secondary effects resulting from potential resource
such as are often used in New England, may be a means of shortages. Also, the secondary effects of energy shortages
carrying out the task. on jobs, transportation, etc., will be difficult to estimate
without sophisticated models of the local economy and
SCARCE RESOURCE CONSUMPTION probably can be disregarded unless some obvious significant
impact is apparent.
Measure 11. Change in the frequency, duration, As in the case of pollution measures, energy impacts
of most individual developments are likely to be too small
and magnitude of shortages of critically scarce to be significant. Cumulative effects of groups of develop-
resources, and the number of persons affected. ments need to be considered. Alternatively, for an indi-
The effect of new development on consumption of vidual development, the efficiency with which it uses
scarce resources, especially energy and fuels, is of increasing energy resources might be estimated, in terms of expected
energy usage for heating and cooling in equivalent BTU's or
concern today.30 Individual developments are unlikely to KWH per square foot of usable interior space per year. The
make a significant difference in local energy consumption, degree to which the structure will conserve energy may be
except where the development is very large or if shortages compared to local or national standards, or to local averages
are very critical. Also, local energy problems tend to be for recent developments of a similar nature.32 Measuring
overshadowed by regional and national energy policies. efficiency may also be useful where the computation of
Nevertheless, new development collectively can influence energy shortages is too complex, such as when the local
local shortages. And at the minimum the efficiency of supply is subject to large unpredictable fluctuations.
resource utilization can be estimated for individual develop- Measuring the change in consumption as a result of
ments. The discussion below is directed to electrical energy, development needs to take into account that some usage
natural gas, heating oil, and gasoline, but the general idea simply shifts within the community and does not materially
applies to any critically scarce resource, the shortage of affect overall consumption. For example, when a family or
which affects people's well-being and way of life.31 industrial plant relocates within the same community, the
Evaluations should focus on the frequency, duration, net change in consumption may go up or down, depending
and magnitude of shortages, that is, when demand exceeds on whether it uses more or less energy after the move, and
supply. For example, the finding might be: "An expected whether a comparable user moves in to fill its previous
additional two brownouts lasting up to three hours per quarters. Also, usage per existing household or business
year." This is intended as a proxy for the degree of may change over time and must be considered or forecast
inconvenience created. People generally will recognize how when estimating the likelihood of shortages.
this would constrain or inconvenience them in terms of
Energy generated within a development itself, as in
restricted use of television and other major appliances, but the case of an industry or apartment complex burning its
it might be desirable to explicitly describe the types of solid waste to create power or heat, should be subtracted
appliances, lights, etc., likely to be affected to bring the out of the requirements of the community.
point home. Fuel oil shortages may be expressed in terms
of temperature reductions. Electricity
For electrical energy consumption, the suggested
30. A short summary of the energy problem and some measure for large developments or cumulative effects of
potential solutions may be found in Gordon A Friedlander,
"Energy Conservation by Redesign," IEEE Spectrum, November 32. Friedlander, op. cit., stat@s that if 75 percent of new
1973, pp. 36-43. housing units complied with recent FHA ingulltion standards,
savings over the next decade would equal 24 x 101 KWH,whichis
31. Of course, most resources are scarce. The emphasis more than the energy produced by present annual consumption of
should be on those few deemed most important. all fossil fuels.

Natural Environment 65

development is the expected number of brownouts (voltage or delivered in reduced amounts to all customers as in
reduction) or blackouts (no electricity) per year, and the electric power brownouts. Thus, unless ample future
duration of the "out." For individual small developments, supplies are reasonably assured, the gas utility itself may
the efficiency measures previously cited might be used. withhold gas altogether from new development. If gas is to
It would also be useful to translate voltage reductions be used, one would try to measure the resulting number of
into their more noticeable effects, such as whether lights existing customers required to switch to another fuel or the
would be dimmed or air conditioners unable to operate. average change in home temperatures due to short supplies.
Deliberate brownouts ordered as safety measures by the In any case, the measure used should be adapted to reflect
power company and accidential brownouts or blackouts the allocation procedures used locally, and efficiency
should be distinguished. measures used for evaluating small developments.
For assessing the impact of past developments, data
on usage rates and incidents of shortfalls should be available Gasoline
from local utilities. Identifying the extent to which added Because gasoline is allocated at community-wide,
consumption in a development caused or aggravated short- regional, and national levels, localized shortages usually will
falls will also require data on changes in usage for existing not be computable or even make sense to consider for
(predevelopment) units, changes in supply, and changes in particular developments and possibly even groups of devel-
energy allocation policies. opments. But individual developments do influence demand
Electrical energy requirements for proposed resi- by the degree to which they affect the numbers and lengths
dential and commercial developments can be estimated
from established local averages for analogous recent devel- of private vehicular trips. Thus the change in the number of
opments, or from design details of the development and car-miles per capita to be required by the development
assumptions about the behavior of the development's users. relative to per capita usage in the rest of the community,
and the number of persons in the development within
Adjustments can be made for anticipated energy-saving walking distance of everyday shopping needs or other
features such as extra heavy insulation, or for energy- facilities might be used as surrogate measures of the
wasting features such as glass walls. Estimates for industrial efficiency of resource utilization. However, such measures
development depend on the nature and level of planned may not clearly reflect whether a development's location
production, and data will probably be available from the will lead to excessive gasoline consumption, especially in
industry itself. communities with much room to grow. What might appear
The estimated electrical energy requirements, to- an inefficient location in the short term might prove
gether with assumptions about changes in current custom- efficient in the long term as the area develops. For example,
ers' usage and the supply likely to be available to the the first phase of a new development far from food and
community, can be used to estimate the potential for other stores may not seem optimally located, but the
shortages. In many cases, the local power company can location of the stores may be optimum once the entire
provide most of the needed data, if not the results development is completed.
themselves, since they too obviously must be concerned
with potential shortages. NATURAL DISASTERS
Fuel Oil Measure 12. Change in number of people and
Fuel oil is primarily used for heating. The effects of a value of property endangered by flooding, earth-
development on allocating existing fuel oil supply might be quakes, landslides, mudslides, and other natural
expressed in terms of the reduced home or office tempera- disasters.
tures that will be used as the basis for fuel allocation, and
the number of days that businesses or institutions are Natural disasters take a large toll in life and property
forced to close as a result of shortages. Local field oil com- each year, and cost large sums of public money. Yet much
panies will be a major source of data, although the supplies construction goes on in danger zones in the path of these
are increasingly being managed on a regional, multistate disasters -sometimes from ignorance, sometimes from
basis. Here again, efficiency of usage rather than impact in greed, and sometimes because community needs are
shortages should be used for small, individual develop- deemed worth the risks.
ments. In evaluating a change in land use, the risks from
floods, earthquakes, landslides, mudslides, hurricanes, tor-
Natural Gas nadoes, land subsidence over abandoned mines, volcanoes,
Because of the character and distribution of gas, and other natural disasters should be explicitly stated in
supplies cannot readily be rationed to particular customers terms of the property value and the number of people

66 Data Sources and Analysis

EXHIBIT 6

FORMAT FOR PRESENTING THE EFFECT OF A DEVELOPMENT
ON RISKS FROM NATURAL DISASTERS

Additional People Jeopardized Additional Property Value
Jeopardized
Type of Disaster Within Outside Within Outside
Development Development Development Development

(millions of dollars)

Roods

Worst in 10 years 1,000 0 $10 0

Worst in 50 years 3,000 100 $40 $.5

Worst in 100 years 3,000 100 $40 $.5

Earthquakes

Worst in 10 years 0 0 0 0

Worst in 50 years 500 0 $5 0

Worst in 100 years 1,000 0 $15 0

NOTES: 1. The zero entries do not mean that there would be no damage, but rather that there would be no added jeopardy as a result
of the proposed development.
2. If historic experience is not available, other measures of seriousness may be relied on.

whose residences and places of work will be jeopardized. mation, coupled with the plans for building locations,
The people and property at risk should be indicated for heights, terrain re configuration, construction materials, and
disasters with various probabilities of occurence, such as the planned defensive measures, can be used to estimate the
risk from the worst flood expected every five years, every number of people and value of property jeopardized. This is
ten years, every 50 years, etc. generally more feasible to do for hazards to the new
A new development also might increase the hazards development than for its effects on the existing commu-
to the rest of the community. By removing natural barriers, nity. The effects of changes in land cover and storm
changing land contours, and contributing to changes in drainage on flood severity and frequency in the existing
vegetation and soil permeability, for example, a new community can be estimated using hydrologic (discharge)
development can expose previously safe parts of the models incorporating land cover variables. These models
community to flood dangers. One development may not have to be tailored to each community.34
significantly affect land cover, but a series may. Cumulative The National Seismic Risk Map of the United StateS35
impacts and trends, as well as immediate changes, are can be used to determine whether a community is in a high
crucial. risk area for damage from tremors or earthquakes. A variety
A development can add to community safety by of more detailed maps are available or under development
reversing or reducing previous hazards. For example, it may for some areas; they show where landslides have occurred in
allow people to relocate their homes or businesses to safer the past and where geologic fault lines lie.36 Most areas do
grounds, or it may provide emergency shelter. not yet have detailed risk maps. If they are designated as
The types of disasters to consider vary greatly from high hazard regions on the national map, they should be
one jurisdiction to another. Also, high levels of risk may analyzed for risk by the local jurisdiction's engineers or
apply to the entire jurisdiction or to only the part left for expert consultants.
growth. If there can be no expansion without risk, this Knowledge of construction materials and techniques
must be explicitly weighed against the need for residences for the new development and local meterological conditions
and economic growth. can be used to assess risk from wind, hurricanes, and other
The number of people and value of property jeopar- meterological conditions. Special studies should be made to
dized can vary according to public and private protective assess dangers from other natural disasters.
actions, such as construction of dams. These factors should
be considered in the data collection and analysis. 34. For a discussion of techniques and guidelines for
An illustration of data presentation to assess disaster assessing impact of land cover and storm drainage, see S.E. Rantz,
impacts is shown in Exhibit 6. "Suggested Criteria for Hydrologic Design of Storm-Drainage
Facilities in the San Francisco Bay Region, California," San
In evaluating the impacts of a past development on Francisco Bay Region Environment and Resources Planning Study,
the harm from natural disasters, previous disasters both 1972. One well documented example of a particularized model is
before and after development should be studied to deter- Tennessee Valley Authority, Upper Bear Creek Experimental
Project, A Continuous Daily Stream F7ow Model, TVA, Division of
mine the extent of damage and the number of people Water Control Planning, 1972. Also, Ben Chie Yen, "Methodologies
affected to see whether the changed,land use made any for Flow Prediction in Urban Storm Drainage Systems," Depart-
difference. Usually there will be few if any disasters to ment of Civil Engineering, University of Illinois, Champaign-Urbana,
1973.
analyze, in which case the evaluation would be similar to 35. National Seismic Risk Map, U.S. Department of Com-
that for proposed developments. merce, Environmental Science Services Administration, Coast and
In evaluating the impact of a proposed development, Geodetic Survey, circa 1969.
a number of published data sources can be used. For many 36. See, for example, T.H. Nilsen, "Preliminary Photo-
regions, maps exist showing the flood plains at different interpretation Map of Landslide and Other Surficial Deposits of the
intensities of flooding.33 These maps and related infor- Mount Diablo Area, Contra Costa and Alameda Counties, Cali-
fornia," 1971; F.A. Taylor and E.E. Brabb, "Map Showing
Distribution and Cost by Counties of Structurally Damaging
33. Care must be taken to see how the flood plain is defined landslides in the San Francisco Bay Region, California, Winter of
on such maps. A variety of definitions have been used. For an 1968-69," 1972; and R.D. Brown and E.W. Wolfe, "Map Showing
expanded discussion, see Michael P. Greenberg and Robert M. Recently Active Breaks Along the San Andreas Fault Between Point
Hordon, "Environmental Impact Statements and Some Annoying Delgada and Bolinos Bay, California," 1970, all part of the San
Questions," AIP Journal, May 1974, pp. 164-75. (This includes an Francisco Bay Region Environment and Resources Planning Study,
excellent discussion on water-related impact measurement problems, U.S. Department of Housing and Urban Development and U.S.
too.) Department of the Interior.

68 Data Sources and Analysis

111. AESTHETICS AND
CULTURAL VALUES

This set of measures attempts to reflect the impact of for example, may block the view of green space from an
development on aesthetic and cultural concerns of the existing building. Razing buildings to create a plaza may
citizenry-especially changes in the physical attractiveness open up previously blocked views.
and landmarks of the community-which play important The number of people whose views will become
roles in the enjoyment of life, community pride, psycho- wholly or partially blocked, and the number of people who
logical stress, and land values. But whether they are will gain an improved view through the removal of
measurable, how to measure them, and the degree of obstructions should be estimated. The sightfines blocked by
responsibility which local government should assume for the development and the nature of the old and new vistas
them are less certain-in part because the issues have been can be determined geometrically from plans, maps and
neglected. photos, and by site visits.1
Most people consider the following negative elements For landscapes and cityscapes that are considered
as detracting from aesthetic enjoyment (the pertinent unusually attractive, added data describing loss or gain of
measures are cited in parentheses): blocked views (13), bad views might be desired. The nature of the view might best
odors (5), smoke in the air (5), dirty water (6), and be conveyed using photos or sketches. The fraction of
noise (7). present views that become obscured can also be noted. Loss
Positive elements of physical attractiveness vary with of a particularly attractive part of the view-a waterfall,
tastes. The amount of greenery and open space (8) seems stream, or garden-might be counted as a "major obscu-
significant to many. Other positive elements include wild- ration" even if it represents only a small percentage of the
life and flora (9), local landmarks (16), and the existence of scene. However, a new development should not be scored
"views" (13). However, it is easily recognized that intan- poorly if the panorama in question is already blocked by
gible qualities of design, the balance of structures and previous buildings.
space, and the type of greenery can all add to or detract Distinctions might be made between sightline changes
from what makes an attractive neighborhood, aside from or for residential and nonresidential buildings, when it is
in addition to any specific measure. For this reason, it is assumed the occupants will place different values on them.
suggested that Measures 14 and 15 be used to indicate Certain businesses and tourist attractions are dependent on
citizen perceptions of the overall aesthetic effect. their views, and harm to them should be specifically noted.
Estimating the numbers of people whose views will be
VI EWS blocked is not easy. Should passersby be included? Do you
Icount "windows" or do you count "people" whose views
Measure 13. Number of people whose views or are obscured?
sightlines are blocked, degraded, or improved.

1. For a good description of view protection and regulatory
A new development may interfere with people's views devices, see the American Society of Planning Officials, View
of the scenery or remove obstructions. A new tall building, Protection Regulations, Report No. 213, 1966.

For private residences other than highrises, all occu- Data Collection for Past Development
pants might be counted. For highrises and business estab- People who live or work in close proximity to the
lishments, the approximate number of the occupants or development in question will usually be the most important
daily users whose views will be affected might be noted. group to survey. Other people within sight of the develop-
People affected can be roughly estimated using the average ment and people- in the general community might be
number of occupants per type of housing unit, times the surveyed as well, focusing on broader impressions of the
number of housing units, or by using census or other development's contribution to or detraction from the
population sources. For commercial areas, it is suggested townscape or landscape. Opinions of architects, art critics,
that diagrams be drawn to show the areas from which views artists, urban planners and other professionals might aho be
are obscured, including public areas such as streets. The sought, especially for developments that are large or that
number of people affected can then be roughly estimated. will attract widespread attention and use, such as recreation
4
ATTRACTIVENESS or cultural centers.
To ensure that each person surveyed knows what the
Measure 14. Visual attractiveness of the develop- development under study looks like, photos from several
ment as rated by citizens and "experts." viewpoints or in-person visits may be used. The presenta-
tion media should be consistent for all those surveyed. Each
Measure 15. Percent of citizens who think the person should then be asked to rate the attractiveness of
development improves or lessens overall neighbor- the development and of the previous use of the site (if he
hood attractiveness, pleasantness, and uniqueness had firsthand knowledge of it). Specific reasons for
disliking or liking a development might be asked to
One of the longest lasting impacts of a development is determine, for example, whether the general style, specific
its effect on community attractiveness. Attractiveness design, the structures themselves, or neighborhood compati-
affects people's attitudes toward their community, which bility were decisive factors.
in turn affects property values and the desirability of the Surveys of aesthetic judgments present a number of
community for future growth and investment. problems. Opinions on attractiveness itself may be substan-
The numerous factors relevant to daytime visual tially modified by other aspects or beliefs about a develop-
attractiveness include colors, textures, patterns, and rela- ment, such as its cost, its impact on jobs, the activities or
tion of buildings to each other and to the terrain.2 people displaced, and the people it attracts. 5 A related
However, it is the overall effect, including the movement of problem is that it may be difficult to separate one's
the people and vehicles, that counts. Thus, data describing sentimental feelings for one's old neighborhood from the
or rating the. various design elements are of questionable "pure" appearance of the new development, even when the
value for impact assessment (though possibly useful for latter may appear more attractive or "pretty " to observers
suggesting corrective actions). without any involvement.
Some may- find a new development physically attrac- A variety of more sophisticated techniques might be
tive, but still prefer the original appearance of the neighbor-
hood for its character, image, relation to personal identity,
or familiarity. For this reason a second measure of interest to test. This applies to all perception measures, not just
attractiveness (15) has been introduced. The two may be those on aesthetics. For two interesting but not yet operationally
satisfactory alternatives to surveys, see LE. Shafer, Jr., J.F.
correlated, since overall attitudes expressed in Measure 15 Hamilton, Jr., and E.A. Schmidt, "Natural Landscape Preferences-
may color perceptions of the physical appearance expressed A Predictive Model," Journal of Leisure Research, Vol. 29, No. 173,
in Measure 14. Without further research to confirm this, April. 1970, pp. 1-19, and L.B. Leopold, "Landscape Esthetics,"
however, the two perspectives of 14 and 15 . probably Ekistics, Vol. 29, No. 173, April 1970, pp. 271-77.
should be considered separately. 4. For a description of an experiment to determine the
degree of agreement among art experts and between experts and
Citizen surveys seem to be one of the few systematic laymen on the aesthetic merits of paintings, see J.W. Getzels, and M.
approaches for estimating perceptions of attractiveness, Csikszentmiltalyi, "Aesthetic Opinion: An Emperical Study," pre-
since models for estimating aesthetic preferences are pared for the U.S. Department of Health, Education and Welfare,
lacking.3 Cooperative Research Project 5-080, University of Chicago, 1965. It
was found that artists agree to only a moderate though statistically
significant extent among themselves, and that agreement between
art experts and laymen ranged from fair to poor.
2. Nightime attractiveness might also be considered in
appropriate circumstances. 5. For elaboration of this point, see J.M. Fitch, "Experi-
mental Bases for Esthetic Decisions," in H.M. Proshansky, W.H.
3. Whether surveys will give the same or different data on Ittelson and L.G. Riviin, eds., Environmental Psychology, New
perceptions than may be obtained at public hearings will be of great York, Holt, Rinehart and Winston, pp. 76-84.

70 Data Sources and Analysis

used to ascertain aesthetic opinions. 6 But it is unclear information about the development. Identifying the reasons
whether the added difficulties and expense generally are for dissatisfaction, if any, may provide clues as to whether
justified Instead, questions are suggested that will reflect the aesthetic opinion is based on physical appearances or on
(1) the perceived physical attractiveness and (2) whether other factors.
the citizens feel the new development has increased or
decreased the attractiveness or uniqueness of the neighbor- LANDMARKS
hood. Considering the new land use alone, and then
comparing it with the former use, would permit a finding, Measure 16. Rarity and perceived importance of
for example, that "the new development is rated very cultural, historic, or scientific landmarks to be lost
attractive by most citizens, but they prefer the way the or made inaccessible.
neighborhood looked before. " The data obtained from the
aesthetics survey questions should be viewed in light of Developments may destroy, impair access to, or
other perceptions-about crowdedness, . noise, traffic crowd landmarks such as architecturally important build-
hazard, privacy, friendliness, and overall satisfaction. ings and archeological sites. The importance of landmarks
It should be remembered that people tend to adapt to within a community should be rated (at least qualitatively)
their environment; once a new development has been in terms of rarity, distance to closest similar example,
around, people grow accustomed to its face. The retro- interest to tourists and the public, and interest to scholars.
spective evaluation may be quite different from the Sources for the necessary data include scholars in the
prospective one for the same development. Analysis draw" appropriate discipline, the literature of the field, lists of
from retrospective evaluations for making decisions on official landmarks, historic preservation groups and citizen
proposed developments thus has many risks. surveys.
Rarity may be expressed as the number of existing
Data Collection for Proposed Development examples essentially equivalent to the threatened landmark.
Evaluating the aesthetic appeal of a proposed devel- For example, a particular archeological earthworks might
opment can also be attempted using survey techniques, but be described as one out of 100 known examples of its kind,
this poses two major additional problems: how to convey and one out of three of its size. An architectural landmark
an accurate impression of what the development would might be described as one of the three multistory buildings
look like, and how to correct for the widely varying by a famed architect, and the last with certain features
amounts of hearsay information and prejudices about the representative of its period.
proposal that different citizens will have built up at the Distance to closest similar example may be expressed
time they are interviewed. in miles or travel time to indicate the degree to which
Comi-non devices for representing the development removing the landmark would curtail opportunity for
site and its surroundings are architectural plans, artists' enjoyment or learning.
sketches, aerial and street level photos with the develop- Importance or interest to the public has often been
ment drawn in, and three-dimensional scale models. The neglected but should be taken into account. The percent of
relation between a person's evaluation after exposure to a the public feeling a landmark is worth saving can be
photo or model and the same person's evaluation after obtained by a survey of citizens. A small random telephone
firsthand experience has not yet been experimentally survey of as few as 30 to 50 respondents would probably
determined.' Therefore, records should be kept of which suffice in most cases to estimate the intensity of feelings
presentation modes were used and what background mate- about whether to save-or remove-the landmark in ques-
tion. A simple query could categorize a landmark as "a
rial was presented. must to save," "important to save," "nice, but not
To help offset possible distortions from prejudices, important," "don't care," or "an unpleasant feature that
the survey should be conducted early in the review process should be removed."8
and each person surveyed should be given the same basic Tourist usage and enjoyment may be expressed in
two ways, (1) as annual attendance figures, and (2) as
6. These include adjective checklists, the Gough adjective subjective ratings based on attention in domestic and
checklist, activity and mood checklists, and semantic differentials
tests. In these methods, rather than being asked for a single overall foreign guidebooks, queries to travel agents, and surveys of
impression, the interviewee would be asked to check off which tourists visiting the landmark. The rating scale could be
adjectives best described the development from a list he is given, or
he chooses where the development lies between the pairs of
adjectives such as beautiful-ugly, gay-sad, and cheerful-depressing. 8. Most developments will not interfere with landmarks, and
this survey will be infrequently needed. Also, survey questions could
7. Kenneth H. Craik, "Tlie Comprehension of the Everyday be part of one integrated questionnaire used to obtain data
Environment," Environmental Psychology, op. cit., pp. 646-658. simultaneously for several measures of perceptions.

[Paragraphs in italics deal with retrospective analyses]
Aesthetics and Cultural Values 71

similar to that used in the Michelin tourist guides-zero to American history, architecture, archeology, and culture,
three stars, corresponding to ordinary, somewhat inter- and to similar local or state registers.
esting, worth a detour, and worth a journey. Local officials Importance to scholarly disciplines-how critical a
also should refer to listings in the National Register landmark is for research or teaching-may be determined by
(established as part of the 1966 Historic Preservation Act) seeking opinions from historians, artists, scientists, and
for sites, buildings, and objects of national significance to members of architectural and historical review boards.

72 Data Sources and Analysis

IV. PUBLIC AND PRIVATE SERVICES

This section deals with measuring impacts of develop- Because most large jurisdictions and many small ones
ment on the quality of the traditional major line services have building and health codes and other legal provisions to
provided by local government-Water, public health, crime regulate new developments, measures of structural safety
control, fire protection, recreation, education, and trans- and public health impacts are not included in the measures
portation. Effects on some other line services, such as in this report. ne codes, however, generally are minimum
pollution control and storm drainage, are included in standards, and there may be large variations in risk even
Measures 5-12 dealing with the natural environment. from hazards they protect against.
Developments affect demand for services and the For example, flood hazards vary depending on where
environment in which they are provided and thereby the buildings are located and how they are constructed. Fire
quality of services. Although government interest is mainly -hazards vary with the building materials used, their furnish-
centered on public services, it should consider development ings, architectural details, and whether windows can be
impacts on the quality and quantity of some private opened, even if there are no code violations. Thus there is
services as well, since there is much interaction between the need for evaluating the effects of a development on at least
two. For example, the addition or removal of private some aspects of public safety and health even if it complies
swimming pools may affect the crowdedness of public with all existing codes and ordinances.
facilities. Therefore, it makes sense to measure the impact Finally, it may appear strange to see measures of
of development according to functions or types of services, shopping included with considerations of public services.
whether provided by public or private sources. Yet local government does affect shopping opportunities.
The degree to which services are affected by develop- Government, for instance, designates areas to be used for
ment is closely tied to the predevelopment quality of commercial enterprises through master planning and
service, the resulting changes in public spending, and the zoning. So it is appropriate to consider how proposed
remaining capacity of existing facilities. Fiscal impact development will affect accessibility and other aspects of
estimates, as noted earlier, may not reflect localized or shopping.
short-term changes in service quality. Fiscal studies are
often based on the presumption that the existing level of
service will be maintained, whereas in reality construction DRINKING WATER
of facilities or budget outlays may lag behind need. The
studies frequently assume that per capita costs of main-
taining service quality will remain constant, failing to Measure 17. Change in the rate of water shortage
account for rising costs. incidents.
The fiscal study alone may not point out particular
service problems that may arise even though overall Measure 18. Change in indexes of drinking water
spending levels and facility plans seem satisfactory on the quality and safety.
surface. Thus both the fiscal impacts and actual service
impacts need to be measured to describe the tradeoffs Development may affect water quality by polluting
between the two and how each dimension may change over surface and ground water sources or by increasing demand
time. so that supplies must be drawn from inferior sources. In

either case, drinking water may be made safe, but purifica- Data Collection for Proposed Development
tion processing may affect aesthetic qualities and raise Projecting whether there will be water shortages can
water costs. Added demand from development may also be based on known usage rates for various business and
occasionally cause shortages, necessitating rationing of household characteristics applied to the development plans.
water for bathing and watering lawns, or even for drinking. Projected usage by the development would be compared to
New development might also lead communities to available supplies, expected rainfall, and general use trends.
utilize modern water purification and reclamation tech- Proper planning usually can preclude water shortages,
nology, such as recycling of water, which might improve although occasional lags,in facility capacity may occur.
quality and quantity possibly even at lower costs.' (How- Expected change in water quality can also be pre-
ever, it is more likely that unit costs will increase, which dicted under some circumstances. For example, the ex-
should be considered in cost/revenue analysis.) pected characteristics of water after treatment with new
Except for a very large development relative to processing techniques can be provided by water engineers.
community size, no single land use proposal is likely to They should indicate whether water quality changes are
cause significant changes in drinking water. However, a likely to he noticeable or objectionable by none, some, or
series of developments may. most of the community. If hazardous pollutants will be
increased, it is important to estimate how close these will
Data Collection for Past Development approach safety limits.
77ze frequency and duration of incidents of water HOSPITAL CARE
shortage in the community before and after development Measure 19. Change in number of citizens who are
can be obtained from the records of the city manager or beyond x minutes travel time from a hospital
mayor's office, the water engineer, by citizen survey, and emergency room (using such time as the commu-
from newspaper files about requestsfor voluntary cutbacks nity considers reasonable).
in water use. Also, many fire departments monitor and
record water pressure changes to ensure they meet fire- Measure 20. Change in average number of days of
fighting requirements. waiting time for hospital admittance for elective
Health officials regularly sample water to determine surgery.
bacteriological and chemical impurities, taste, odor, and
turbidity. 10 Sample records before and after development The main effect of most developments on the quality
should be compared. Citizen surveys can determine changes of local hospital care will be on the crowdedness of existing
in how much water people drink and their opinion of the facilities and the accessibility of existing facilities to both
water's taste, odor, and appearance. Surveys are especially the newcomers and the existing residents. Large develop-
useful in instances where the aesthetic factors change, or ments or cumulative demand from developments may also
where water quality becomes a public issue. stimulate construction of new hospitals, which may im-
The basic problem in analyzing data will be isolating prove the quality of hospital services available to the
the changes due to development. If the development
requires new purification techniques or if new kinds of existing community, as well as uncrowdedness and
effluents are added, direct effects will be more apparent. accessibility.
Usually the development simply adds to existing problems, The location of a development with respect to nearby
so its incremental effects must be separated from water hospitals and local traffic conditions affect the travel time
quality changes due to general community growth. to reach an emergency room from the development.
Needless to say this may be a life or death issue. If the
development changes local traffic conditions, the travel
time for persons in the surrounding community may be
9. New technologies are being tried in lake Tahoe and affected as well. If people in the community (other than
Colorado Springs. See "Wastewater Treatment Processes and the those in the development) are not affected, the measure
"Creation of Reclaimed Water as a Commercial Product," Second niight be restated as average travel time for a person in the
Urban Technology Conference, San Francisco, 1972, AlAA, New development to reach an emergency room.
York. Average waiting time in days for admission to a
10. For water quality standards, see U.S. Department of hospital for elective surgery is an indicator of the crowded-
Health, Education, and Welfare, Public Health Service Dfinking ness of local hospitals. Waiting time may also be affected by
Water Standards, Revised, Washington, D.C., 1962. Standards are
controversial for some types of pollutants, especially with regard to factors such as community health conditions, admission
long-range effects on humans. policy, health insurance, personal income, and doctors'

[Paragraphs in italics deal with retrospective analysesl
74 Data Sources and Analysis

policies about hospitalization. These may overshadow especially in residential areas. Developments may affect
changes as a result of development. crime rates in a community by adding or removing targets
(people, businesses, residences) and by changing physical or
Data Collection for Past Development social conditions that may breed crime or make.it easier to
The percent of people within x minutes of emergency commit crimes.
rooms can be computed using a map showing location of The potential targets for economic crime may change
hospitals with emergency rooms and the population distri- in number, density, vulnerability, or lucrativeness. For
bution of the community. Travel time will vary by time of example, a new office building may increase the oppor-
day because of traffic conditions. Peak and off-peak times, tunities for larceny. Crime attracted by the development
or the time of day when most emergencies occur, should be may spill over into the existing community or the develop-
considered. ment might attract crime away from the existing commu-
The average waiting time for admission and the nity. Either way, whether there is a net change in crime is a
percent of capacity may be obtained from hospital records complex issue. It is partially a function of how well the
or possibly from a survey of doctors using nearby hospitals. existing community is known and being "worked" by
If overcrowding exists, data on average stays, changes in criminals, and of relative conditions in the new and old
hospital or doctors' policies, and the percent of patients areas. The vulnerability d the new development can be
coming from areas of new development should be collected decreased by such factors as lighting, guards, surveillance
to help determine if it is due to new development or to systems, clear fields of view, and pedestrian activity after
increased usage by the existing community. dark; it can be increased by ease of building entry, and
unattended out-of-sight stairs, hallways, and basements.12
Data Collection for Proposed Development As examples of the affect of socioeconomic factors
Estimates of travel times should take account of the on crime rates, economic crimes may be reduced if the
location of new hospitals to be built and expected changes develop ment reduces unemployment rates, while vandalism,
in traffic computed for the transportation measurements. car thefts, and narcotic offenses might be expected to
Expected changes in waiting times can be computed by increase if the teenage population increases.
assuming some frequency and duration of hospital visits The ability of police to deter crime might be affected
based on local experience with people with socioeconomic by development. Increases in noncrime duties, such as
characteristics similar to those of the incoming population, traffic control, may reduce the time available for patrol
or more simply, based on current per person usage in the duties. The size of the force may not increase fast enough
community. Preferably, trends in per person usage should to keep up with the new growth. People in the new
be considered, and not just usage at a point in time. A community may not cooperate as willingly with police on
major problem in estimating crowdedness for individual crime prevention or detection. And response time to crime
hospitals is that people tend to go to hospitals associated calls may be increased because of increased traffic con-
with their doctors, or reported to be especially good for the gestion.
service they seek, and not just to the nearest hospital. How people perceive their safety is as important to
Unless there is a regional hospital shortage, or usage models them as actual crime rates. Therefore, the degree to which
developed for the region, it may be difficult to estimate citizen feelings of security are affected in the neighborhood
waiting times for specific hospitals. of the development should be estimated.

CRIME CONTROL Data Collection for Past Development
Measure 21. Change in rate of crimes in existing The most recognizable crime impacts are likely to be
community or new development (or expert rating in the immediate neighborhood of the development. Crime
of change in hazard presented). rates by type of crime should, therefore, be determined for
Measure 22. Change in percent of people feeling a the periods before, during and after development in the
lack of security from crime. police district containing the development, and in the
adjacent districts.
Potential changes in crime rates" and perceived crime
hazards are a prime issue in many rezoning evaluations, 12. For interesting discussions on how urban design might
affect crime, see Oscar Newman, Defensible Space: Crime Pre-
11. Oime rate here signifies the number of crimes against vention through Urban Design, New York, Macmillan, 1972; and S.
residents per 100 residents per year and the number of crimes Angel, "Discouraging Crime through City Planning," University of
against businesses per 100 businesses per year, and not just the California, Institute of Urban and Regional Development, Working
absolute total of crimes per year. Paper No. 75, 1968.

Public and Private Services 75

01me rates for the areas outside and within the before to after development and the reasons for any
development should be estimated separately to distinguish changes, to learn if they are related to the new develop-
between effects of development on the existing communiry ment. There has been considerable experience under LEAA
and on people in the development. The new development sponsorship of surveys that attempt to gauge feelings of
might have a high crime rate and affect the overall security. Typical questions ask whether the person feels
community crime rate without increasing the rate, of crimes safe walking alone in the neighborhood at night and in
against those outside the development. daytime.
Change in crime rates in the neighborhood with the
development should be compared to changes in comparable Data Collection for Proposed Development
neighborhoods used as controls to determine if the changes For most new developments it will not be possible to
may reasonably be attributed to factors in the development make reliable estimates of their impact on crime. Knowl-
under consideration. edge about the quantitative relationship between crime
The crime categories for which rates should be rates and the causes of crime is limited, and wholly
compared include those in the FBI crime index (murder, satisfactory methods of predicting crime rates do not exist.
rape, assault, robbery, larceny, auto theft), serious narcotic Crude approaches, however, might be tried on the premise
crimes, and vandalism, and any other crimes of particular that an educated guess is usually better than pure con-
concern to the community. Data on index crimes are jecture.
collected by most jurisdictions by month andyear. Data on Crime rates in the new development can be roughly
other crimes, and data on crimes by police district, estimated based on knowledge of an area's current crime
neighborhood, or precinct also are often available. Some rates and trends by type of business or residence. For
police departments keep track of where crimes occur with example, Detroit keeps data on the number of burglaries
pins on a map, simplifying data collection for specific and larcenies by type of business (e.g., department stores,
neighborhoods. groceries, etc.) and type of residence (e.g., single-family
It is important to remember that available police data residences, apartments).13 These data can be applied to the
usually refer to reported crimes, not total crimes com- number of establishments or units of each type in the
mitted. A new development may change the -percent of development plan.
crimes that are reported in some crime categories, perhaps A second approach is to draw analogies from previous
as a result of improved or worsened police-community experience with similar developments in similar neighbor-
relations. Total crime can be estimated from victimization hoods. The detailed design of the buildings, open space,
surveys (interviews to determine the actual number of lighting, types of activity by time of day, etc., should be
crimes that occurred whether reported to the police or considered, not just the general land use. If, in spite of
not). Unfortunately, unless a victimization survey is made variations in certain details that-will almost always exist, a
within the development, the usual citywide surveys prob- particular type of development in a particular kind of
ably will not contain a large enough sample of persons i .n neighborhood usually resulted in a significant crime in-
the development to distinguish between the degree of crease, it would be reasonable to expect a similar result in
underreporting within and outside the development. How- like circumstances. The estimated change might then be
ever, a major change in underreporting in the part of the stated in qualitative terms such as the likelihood of major
city containing the development may be detectable from increase, minor increase, or no significant change. On the
the general surveys. A special victimization survey for the other hand, if case histories show vast differences in crime
development might be coupled with survey questions for rate effects for developments similar in gross characteristics,
other measures in a multipurpose survey to aid in assessing one would have to conclude that wide variations could
impacts of development. result, stating frankly that the elements which cause high or
7he number of persons living in the development who low crime impacts have not yet been identified, and that
were arrested for crimes in the community might be estimates either way are unreliable.
another indicator of how the development contributed to The gross analogy approach has the advantage of
crime patterns. Comparable data ftom the previous land use treating the totality of changes, indicating impact on the
should also be collected so the before-and-after differences surrounding community and not just on the development
can be fairly analyzed. site itself. In addition, it might give an indication of how
Data for the second suggested measure, the change in leelings of security might change. But it must be considered
the percent of people feeling a lack of security from crime, a speculative approach until there has been an opportunity
can be obtained from citizen surveys conducted before and to subject it to considerable further testing.
after development. The second survey might ask about
changes in the feeling of security over the time period from 13. Detroit Police Department, 1971 Annual Report,

[Paragraphs in italics deal with retrospective analyses]
76 Data Sources and Analysis

FIRE PROTECTION 0 Adequacy of amount and type of firefighting
equipment and personnel in light of the needs
Measure 23. Change in fire incidence rates. of the new development, such as special fire
towers for highrise buildings.
Measure 24. Change in rating of fire spread and
rescue hazards. Note that development may lead to improved fire
suppression for the community by providing enough
Fire hazards are infrequently mentioned in land concentration to warrant additional fire houses, fire person-
development evaluations. This is partly a tribute to the nel, and special equipment that will be available most of the
success of building code enforcement and modern fire time for standby protection to the rest of the community.
departments in preventing fires and keeping them from
spreading. But it seems also to stem from an under- Data Collection for Past Development
appreciation of the hazards that remain. For example, in Most communities keep fire records that can be used
many modern buildings serious hazards may persist from for estimating the impact of past development on fire
(1) the smoke of even small fires because their windows incidence. These records permit fire incidence rates to be
cannot be opened, (2) materials that give off toxic fumes determined by type of building structure, and by type of
when ignited, and (3) the difficulties in escaping, especially business or residence. Data on the extent of damage and
from highrise structures. spread offires for various structures, though less commonly
Fire hazard from new developments may be consid- used than incidence rates, can also be collected, 14 Arson or
ered in two parts: the change in the likelihood of a fire false alarms attributable to residents or others associated
getting started in the first place, as measured by fire rates, %4th the old and new land use might be compiled from
and the change in the likely spread and risk to life of fire police and fire department records. Changes in fire insur-
once started. The issue goes beyond risks to occupants of ance ratings, if any, would give further clues for assessing
the new development; it concerns other members of the the hazardfirom new development.
community who may visit, work, or shop there; it involves
the potential spread of fire to the rest of the community; it Data Collection for Proposed Development
may mean added risks for firemen; and it may increase fire
protection costs generally. Expected fire incident rates can be estimated from
Fire incidence may be affected by many aspects of the community's past experience by type of structure or
new development: kind of business or industry. When there are few or no
0 Types of construction and materials. buildings or situations comparable to the expected develop-
ments, the data might have to be supplemented by
Equipment, processes, and activities in the information from nearby or similar communities. Rates for
development. residences should preferably be further subdivided by
demographic and socioeconomic characteristics, although
� Education level, age distribution, and attitudes this kind of breakdown is not yet available in most
of new entrants into the community (which jurisdictions.
have a bearing on arson, false alarms, and Because it is probably not possible with the current
accidental fires). state-of-the-art of fire protection to quantitatively describe
the probability of a certain degree of spread, damage or
� Character of previous development (removal of injuries, we suggest using a qualitative rating as to the risk
blighted buildings, for instance, would probably of fire spreading from the new development to the rest of
reduce fire hazards). the community, noting any special problems that might
hinder or increase the danger of firefighting and rescue
Fire spread may be affected by the above factors, and operations. The rating would be based on expert opinions
others: from fire engineers or the fire department as to the change
in hazard level to the community, taking into account
0 Overall design, street layout, and proximity of changes in the fire department as well as the plans for the
buildings to each other. proposed development. Any anticipated change in fire

0 Hydrant locations and built-in private fire 14. A method for measuring fire spread is disc-assed in P.S.
defenses. Schaenman and J. Swartz, Measuring Fire Protection Productipity in
Local Gopernment-Some Initial 7houghts, National Fire Protection
0 Distance to nearest fire station. Association, Boston, 1974.

Public and Private Services 77

insurance ratings as a result of equipment changes or other removed by the new development. The 'Y' distance would
factors should be explicitly stated. be a criterion chosen by the community; it would be
different for different types of facilities such as pools or
RECREATION neighborhood playgrounds. These distances can be deter-
mined from maps with travel time or distance contours
Measure 25. Change in the number of people around specific facilities superimposed on plots of esti-
w .ithin-or beyond-a reasonable distance (x miles mated population distributions. 'Me travel times would be
or y minutes) from recreational facilities, by type computed by mode of travel (e.g., walking, car, bus), taking
of facility. into account local conditions such as physical barriers.
The second approach emphasizes loss of access and
Measure 26. Change in usage as a percent of may be used when a facility is eliminated by the new
capacity; waiting times; number of people turned development or made virtually unusable because of an
away; facility space per resident; and citizen increased hazard, extreme environmental changes, or by
perceptions of crowdedness at recreational facili- construction of physical barriers to it. In this case, the
ties. number of different people or families using the facility,
the attendance rate, and the distance to the nearest
Measure 27. Change in perceived pleasantness of equivalent facility might be used to.reflect the extent of
recreational experience. reduced recreational opportunities.
The number of people or families using a public
Development can affect the variety, accessibility, recreational facility can be estimated with citizen surveys,
crowdedness, safety, and overall enjoyability of recreation such as are starting to be @used by a few recreation
in the community by adding or eliminating facilities, by departments." Attendance figures for the facilities do not
changing the numbers and types of potential users, and by describe the number of different users (as opposed to
changing the environment around recreational facilities (by repeaters), but they do give a good indication of the
polluting the air for instance). The facilities affected may intensity of usage by the community. For private facilities,
include informal open spaces such as empty lots, sidewalks, membership rolls are usually available. Commercial recrea-
and streets used by children or adults, as well as tennis tion facilities such as bowling alleys generally keep atten-
courts, swimming pools, picnic areas, gyms, playing fields, dance statistics.
riding stables, boating areas, beaches, woodland trails, and The distance to the nearest equivalent facility is
so forth. usually easy to deternidne, but whether that facility can
Even where the facilities affected by the development handle the potential increased demand is less obvious. (See
are private and restricted to a special group, such as pools discussion of crowdedness estimates below.)
for residents of highrises, they can affect the demand for What is an acceptable distance to a substitute facility?
publicly provided recreational service.15 This will vary with the age and nature of the clientele
group. For example, a new development may displace an
Accessibility open lot-the informal play space of neighborhood chil-
dren. An alternate site may be well within walking distance
There are at least two ways to assess a change in and a satisfactory substitute for older children, but parents
access to recreation facilities. One emphasizes potential who want to keep their younger children within sight and
availability of facilities to all citizens, whether or not they sound range may consider it unacceptable.
use them. Jbe second emphasizes the inconvenience to
current users when an existing facility is to be affected. Crowdedness
Basically the same approaches apply to evaluating past and The impact of development on the crowding of
proposed development. recreational facilities may be described in terms of waiting
Under the first approach one may identify the change times at facilities, number of people turned away, potential
in the number of persons (by age group) within (or not users per facility, space or facilities per resident, or usage as
within) "x" distance of types of facilities to be added or a percent of operating capacity (where the latter is a
meaningful statistic). Citizen perceptions of crowdedness
15. For a further discussion of recreation measures see, H.P. are also important to consider.
Ibtry and D.R. Dunn, Measuring the Effectiveness of Local
Government Services: Recreation, Washington, D.C., The Urban
Institute, 1971, and How Effective Are Your Communitv Recrea- 16. Ibid. See references listed for a discussion of utilization
tion Services?, U.S. Department of Interior, Bureau of Outdoor of citizen surveys to collect information on recreation usage and
Recreation, prepared by The Urban Institute, 1973. many other kinds of data.

78 Data Sources and Analysis

For evaluating past developments, actual changes in ment, for facilities whose environment or demand is
the crowdedness of facilities can be measured. Before and affected by the development. A second indicator could be
after waiting times can be determined from signup sheets or the percent of previous users still in the community who
estimated by staff at the facilities. Observers can estimate continue to use the facility, with the assumption that an
the number of turnaways. Ricorded attendance and design attendance loss reflects decreasing pleasantness. For ex-
capacity are sometimes known and can be used to compute ample, x percent of the children using a public playground
the percent of capacity used. And citizens can be surveyed may stay away after a tougher group of children arrive. Or
to determine if they feel the facilities are too crowded. y percent of the previous swimmers stop using a beach
For evaluating proposed developments, rough esti- because of pollution caused by a new plant. Periodic citizen
mates of changes in crowdedness of major facilities, such as surveys of use patterns and reasons for nonuse could
pools and tennis courts, can be made. The specific furnish much of the necessary data.
facilities-old or new, public or private-most likely to A simpler but less satisfactory approach would be to
attract people from the new development can be identified. consider before and afte-r changes in attendance figures for
Then the fraction of people in the new development likely nearby facilities, as compared to changes in attendance at
to participate in each activity would be estimated according facilities in areas not affected by development. This would
to the expected age, sex, and income distribution of the suggest whether a facility is still considered relatively
new residents, applying rates of usage for comparable enjoyable.
people in the existing community. Accuracy of these For evaluating proposed developments, a qualitative
estimates will be limited by many external factors that can description of changes in the environment at recreation
affect usage, such as changes in amounts of leisure time sites, and judgmental statements as to whether they are
people have, or the energy shortage. It is also affected by likely to affect enjoyment should be made. Quantitative
incomplete knowledge of how well the people will be projections about how citizens are likely to perceive
informed about a facility's existence and how crowded, pleasantness is beyond the current state of the art.
safe, and attractive they will find it-factors which. appear
to affect rates of usage. Accuracy is also limited by the EDUCATION
general lack of data in many communities on usage rates for
various demographic and socioeconomic groups. Some Measure 28. Change in number of students within
communities are just starting to identify and explain usage x minutes walk or y minutes ride from school, by
patterns for their existing population, however, so the type of school.
prospects for better data seem to be improving.
As a poor substitute, current attendance per capita Measure 29. Number and percent of students
figures might be used to project expected usage and then having to switch schools or busing status (from
see whether these results exceed facility capacities. The walking to busing or vice versa).
minimal and simplest approach would be to identify nearby
facilities, determine which are near or at capacity (or where Measure 30. Change in crowdedness "breakpoints"
significant number of users already feel too crowded), and (such as need for added shifts) or indicators (such
use judgment to estimate whether the new development is as student-teacher ratios); and student, teacher,
likely to push them over capacity, and cause more intense and parent perceptions of crowdedness and pleas-
feelings of crowdedness. antness of schooling.
If the new development provides additional rec-
reation'facilities, the estimated number of people who New development can change the numbers, age
currently use other facilities and who are closer to the new distribution, and special educational needs of school chil-
ones could be subtracted from attendance figures of these dren in the community. These can affect the location of
current facilities to indicate the decrease in crowdedness new schools and where pupils are assigned, which in turn
there. This is not as simple as it may seem, since usage is may affect the crowdedness, convenience, and pleasantness
affected by the available supply, and the old facility may of the schools.
become just as crowded as before. Also, users may not Development may also enhance the variety of educa-
automatically switch to the more convenient facilities. tional experiences available to the community by providing
Pleasantness the critical population mass necessary to warrant junior
colleges, special classes for the educationally handicapped,
For evaluating past developments, user surveys can experimental schools, vocational programs, and the like.
estimate directly the change in the perceived pleasantness Development may affect the quality of education in
of the recreational experience before and after develop- the schools, but too little is known about measuring, let

[Paragraphs in italics deal with retrospective analyses]
Public and Private Services 79

alone predicting, quality changes for any recommendations will be heavily influenced by their decisions about how to
to be made here on what to measure. If the current debates deal with increased demands. Qualitative, judgmental esti-
and research on educational quality shed more light on mates of whether there will be any important changes in
cause-and-effect relationships, the findings may be incor- perceived crowdedness and pleasantness should also be
porated in new impact measures. made.
Effects of development on education that can be
estimated, and that are of, considerable interest in the LOCAL TRANSPORTATION
community, are changes in the convenience, accessibility,
crowdedness and pleasantness of schools. For example, how Measure 31. Change in vehicular travel times
many pupils will have to switch schools? How many who between selected origins and destinations.
walk will have to use buses and vice versa? Will severe
crowding result, forcing the schools to go to a two-shift Measure 32. Change in duration and severity of
system? (It should be noted that less pronounced changes congestion.
in crowdedness are difficult to measure meaningfully.) How
will pupil-teacher ratios change? (One should not assume Measure 33. Change in likelihood of finding a
that these ratios necessarily relate to quality of education, satisfactory parking space within x distance from
but the data may suggest possible change in the amount of destination or residence.
attention given to each pupil.) Will present classroom
capacity serve the greater demands? (Stated capacities Measure 34. Change in numbers and percent of
usually should not be taken literally but may serve as residents with access to public transit within x feet
benchmarks of crowding; again, this is not a quality of of their residences; and numbers and percent of
education measure.) Will there be new types of educational employees who can get within x distance of work,
opportunity not previously available to the community? location by public transit.
Data should be collected for individual schools and
aggregated by level of school -elementary, junior, and high Measure 35. Change in the rate of traffic accidents
school-where appropriate. (or expert rating of change in hazard presented).
For evaluating past developments, data on pupil
reassignments, total enrollments, design capacities, and Measure 36. Number and percent of citizens
variety of schools and programs should be readily available perceiving a change in neighborhood traffic hazard;
from the local board of education. Average travel times, if and change in pedestrian usage of streets, side-
not explicitly available, can be computed from maps walks, and other outdoor space.
showing locations of schools, school jurisdictional boun-
daries, population or student distributions, and school Development may affect vehicular travel by changing
busing boundaries. Surveys of students, teachers, and the number and length of car trips needed, by changing
parents could be used to identify changes in the perceptions local street and road patterns, by creating need for
about the pleasantness and crowdedness of the schools additional traffic controls, and by changing the demand and
before and after development. It should be noted that supply for parking space.
changes in school busing policy which modify the neighbor- Development may affect the accessibility and con-
hood school concept may overshadow effects of individual venience of public transportation by altering demand
new developments. patterns, and thus routing, scheduling, and crowdedness.
For evaluating proposed developments, most com- Walking and bicycle riding are too infrequently given
munities have statistics on the number of pupils expected serious attention as forms of transportation. These, also,
for elementary, junior high, and secondary schools per may be affected by development that adds or interferes
housing unit by type of housing. (As discussed for Measure with sidewalks, bridges, paths, and bikeways, that changes
1, these data are also needed for computing educational relative locations of shopping, work centers, and residences,
expenditures and the change in public fiscal flows.) and that alters the traffic hazards to pedestrians and bicycle
Expected increases in demand, balanced against present riders.
school capacity and planned new schools, can be used to Transportation impacts most directly related to new
estimate pupil assignments to various schools and likely developments and likely to be of most concern to citizens
crowdedness. These estimates, in light of known busing include travel times, degree of congestion, parking availa-
policies, will indicate how many pupils will face changed bility, public transit accessibility, and traffic safety. Other
transportation arrangements. The local board of education indicators may be appropriate in particular situations.
must be consulted, since the results of new development Pedestrian accessibility to recreation, schools, and shopping

80 Data Sources and Analysis

is reflected in Measures 25, 28 and 37, respectively. Effects commercial and industrial areas, changes in travel time to
on bicycle transportation should be discussed at least existing business from major residential locations or other
qualitatively where pertinent. As with other impacts, business locations can be used. For both cases, changes in
distinctions should be made between changes in transporta- travel times through the area of the development should be
tion service for the existing community and transportation reported if major through-routes are affected.
service for the new development.17 Except where the road network is quite sparse, such
an analysis often is difficult and expensive. It may only be
Travel Times feasible to collect data on travel times between points near
The only noticeable effect on travel times for many the development and a few representative work, shopping,
develo pments- especially small ones-is likely to be in their or residential locations as discussed above for localized
immediate vicinity or on the nearby portions of roads travel times.
radiating from the area of the development, which receive For past developments, communitywide travel time
the full brunt of the increased traffic load. The nearby changes can be measured by test driving along selected
effects are also often the only ones that can be readily paths before and after development. Work trip times should
estimated without using detailed models of the transporta- be collectedfor a.m. and p.m rush hours,- other trip times
tion network. Changes in average driving speeds might be a should be tested in off-peak conditions. Locations in and
complementary or alternative measure to travel times; around the development for use as one end of the
especially when traffic effects on small stretches of roads in point-to-point trips should be selected carefully because the
the vicinity of the development are the only ones con- effect of the development on travel times may vary
sidered, the absolute change in travel time may not considerably depending on the points' locations with
adequately reflect the potential inconvenience to drivers respect to the exits and internal traffic flows of the
who are forced to drive more slowly than previously. development. 18
For past developments, increased time to get into or 77zere are many practical problems in collecting valid
out of the immediate vicinity of the development and travel time data at two points in time, and then attempting
delays on major roads leading from the vicinity of the to isolate the changes due to the development. Care must
development can be measured by a sample of test runs be taken that time of day, weather conditions, and the
before and after development. paths used are similar. Traffic changes due to changes in the
For proposed developments, the existing street capac- base population or to other developments must be consid-
ities and traffic volumes are usually known or measurable. ered. Also, the traffic load imposed by a development often
To this base the expected change in car trips caused by the changes over time as its novelty wears off, as motorists find
development should be added. The number of car trips new ways to cope with it as its existence becomes known,
generated by each household unit can be estimated based and as its usage builds to capacity. Thus, a retrospective
on the type and price of unit, expected socioeconomic analysis should preferably be made for several points in
characteristics of the occupants, and the expected modal time, to identify the transient effects.
split between car and other means of transportation. A cruder, less reliable approach is to obtain subjective
Similar estimates can be made by type of business for impressions of travel times from drivers who regularly drive
to and from the vicinity of the development before and
industrial and commercial development. From these data after development.
local delays can be roughly estimated and likely bottlenecks For proposed developments, estimating precise
identified. changes in travel times between pairs of points is difficult.
For a development that is large relative to its The most common general approach starts with estimating
community, or for the cumulative effects of a set of the number of vehicular trips that will be generated by the
developments, the change in travel times between major development, based on past trips per household or business
origins and destinations throughout the community should and choices between public and private modes. The
be considered in addition to localized effects. expected traffic volumes on various roads can be computed
For developments in residential areas, the localized by making assumptions as to how the added trips will be
travel time effects can be assessed in terms of the change in distributed throughout the road network during rush hours
travel time to major work or shopping destinations from and nonrush hours, and adding them to existing volumes,
the vicinity of the development, For developments in
taking account of expected changes by current users. The

17. For a more complete discussion of measures of effective-
ness for local transportation see, R.E. Winnie and H. Hatry,
Measures of Effectiveness of Local Government Services: Local 18. Ibid, for a further discussion of measuring congestion
Transportation, Washington, D.C., The Urban Institute, 1972. and travel times.

[Paragraphs in italics deal with retrospective analyses]
Public and Private Services 81

average travel speeds can then be estimated from projected spaces provided by the development or the local govern-
traffic volumes and known street characteristics. ment, the nature of the activities in the development, the
For more than very simple networks, a computer availability of public transportation, existing demand in the
model is likely to be needed to make travel time estimates. neighborhood, and the prices charged for the new parking
The Urban Transportation Planning Process model has been spaces. If the spaces provided are too few or too expensive,
in widespread use for many years. However, such models persons in the development may park in the surrounding
are generally expensive to use and require considerable neighborhood, increasing parking congestion.20
traffic engineering expertise. They are probably not practi- The major parking impact to measure is the change in
cal nor necessary for any but the largest developments or the likelihood of finding an "acceptable" parking space
for estimating cumulative effects, especially if the analyses within x distance from the vicinity of a new development.
are to consider alternative paths drivers may choose as their This can be translated as the probability that a parking
prime choices become too congested. The validity of space exists within x distance at a given time of day and
estimates made with the aid of such models is still within a given price range. In some situations, the analysis
controversial. might also distinguish availability of on-street and off-street
Since there are many assumptions involved in esti- parking, metered and nonmetered parking, and so forth.
mating travel times, a range of possible delays or improve- An alternative or supplementary measure is the
ments should be given along with the best estimate of the change in the percent of people finding parking incon-
average delay or improvement. If the range is wide, that will venient in the vicinity of the development, which, as with
emphasize the lack of knowledge about the likely impact of other perception measures, is more suitable for evaluating
the development. The uncertainty is important to consider past than proposed developments. Another measure, the
in the evaluation. number of spaces on the development site relative to the
number needed to serve the development can indicate the
Congestion potential for parking spillover into the neighborhood, but
The severity of congestion can be defined as the ratio its effect on neighborhood parking depends on the existing
of the maximum time to travel between two points relative parking conditions. Yet another measure, the average
to the "no traffic" or off-peak, law-abiding travel time percent of available neighborhood parking spaces that are
between those points. The duration of congestion can be filled at various times of day and days of week, is a weak
defined as the length of time during which travel times measure of parking adequacy, because of the ambiguity in
between two points is some percentage above the off-peak interpreting it; a low level may indicate sufficiency or
travel time. undesirability of the parking. A high level-close to 100
For past developments, before and after measure- percent-may indicate just the right amount or a shortage.
ments of these two aspects of congestion can be made for The interpretation can be improved by considering the
nearby roads, streets, or major arteries along with travel percentage filled by price range, and other attributes of the
time measurements. 19 parking spaces.
Assessing the impact of a proposed development on For past developments, the before and after change in
congestion requires estimating travel times for several parking availability can be determined by observation, test,
points in time to determine the severity and duration of the or survey. Aerial photos of the neighborhood could be used
congestion. This is difficult to do with sufficient precision in some situations to identify the number of empty parking
using existing models and with the lack of accurate spaces relative to the total number of available legal spaces
knowledge of trip generation. But at least a sensitivity at an instant of time. The turnover will not be identifiable
analysis could be undertaken for larger developments to unless a series of photos is used. (The photos would not be
identify the potential range of impacts that may occur suitable, of course, in situations where there is a lot of
under different, plausible assumptions about their trip underground or covered parking. J
generation. As for the analysis of travel times, it is For proposed development, the measures might be
necessary to consider alternative paths that may be used as roughly estimated from the expected shortage or excess of
congestion increases on the primary ones. parking spaces available in the proposed development for its
own needs, and the number of spaces typically available in
Parking Convenience the adjacent neighborhood (during business and non-
business hours). The latter can be measured by field
The effect of a development on neighborhood observations or aerial photos. The estimate can be crudely
parking will depend on its size, the number of new parking
20. Parking lots and parking spillovers to the neighborhood
19. Ibid. are factors to consider in the attractiveness Measures 14 and 15.

82 Data Sources and Analysis

based on the average deficit (or surplus) of spaces expected 'traffic Hazards
in the neighborhood after development, or on a mathemati- Increased or decreased traffic hazards in the neighbor-
cal model that could be developed for translating changes in hood of the development, especially hazards to pedestrians
parking supply and demand into the expected time to find and children, should be a major concern in impact
a space. evaluations. Both the actual hazard and the hazard per-
Accessibility to Public Transportation ceived by the citizens are important; the latter may have
the greater impact on behavior.
New development may generate enough demand to Changes in accident rates (per thousand people)
allow additional service on existing public transit lines, the caused by increased traffic and special hazards created or
creation or rerouting of lines, or even the start of a new eliminated by development will partly indicate changes in
public transit system. If so, estimates should be made of the the actual hazard. However, even for past developments, it
change in the number and percent of existing residents may prove too difficult to estimate the change in the
within y distance of service from their residences. Distances accident rate for existing residents, or to relate observed
of one-eighth or one-quarter of a mile-roughly a 5 or 10 changes in the accident rate to a specific development, even
minute walk-might be used as standards. More detailed with detailed evaluation studies. In those cases, a proxy
measures that indicate the time it takes to get to representa- measure, the change in the traffic hazard presented to
tive destinations via public transit may be appropriate for residents of the neighborhood, might suffice. It would be
some situations. based on expert opinion of how changes in street and
Whether transit service gets changed or not, it may parking layouts, traffic density, view obstruction, and
still be of interest to the community to see whether the traffic controls combine to change the hazard. If the change
new development will add to or reduce the community's in hazard cannot be expressed as a quantitative estimate of
dependence on autoS.21 This can be measured by the the change in the accident rate, then a scale describing
percent of new residents who will be within y distance of whether the danger is "much greater, somewhat greater,
public transit, and the percent who could reasonably get to about the same, somewhat less, or much less" should be
work by public transit (not that they necessarily will use used.
it). Time limits and walking distances that would define a A sharp increase in actual or perceived traffic hazard
"reasonable" work trip can be defined according to local may curtail street and sidewalk usage by pedestrians,
tastes. For commercial and industrial development, the children playing, and other outdoor activities. This reduc-
measure is the percent of workers and customers who can tion in activity may limit or even reduce the number of
get to the development by public transit. accidents. Thus it is desirable to include an expert hazard
Changes in accessibility of public transportation for rating even where it is possible to measure or estimate
people living near or in a development can be estimated changes in accident rates.
using maps showing local transit stops and the number of The hazard perceived by the community can be
people living within x miles of the stops. The same described in terms of changes in activities that are con-
procedure applies for past and proposed developments. sidered safe. These may range from "sidewalks or streets
The accessibility of a commercial or industrial devel- usable for young children at play" at the safe end of the
opment for its employees or visitors can be estimated for scale to "not suitable for an adult walking" at the other,
past development by surveying them, or, for past and unsafe end of the scale.
proposed developments by estimating whether areas from In estinwting the impact of past developments on
which customers or employees are likely to come are traffic safety, data on reported accidents are available from
partially or wholly accessible by public transit. Planned (or local police agencies, and usually include the location of the
proposed) changes in routes as a result of the development accident. From these data can be sorted incidents that
should be considered. occur on streets near the development. As mentioned
earlier, however, attributing the causes to a particular
development is often difficult, unless an obvious hazard
exists. Expert opinion of traffic engineers and police can be
21. Dependence on autos may be important for more than used to rate the changes in hazard before and after
just air pollution impacts, which are covered in Measure 5. Some development. Perceived traffic hazards can be estimated by
communities have the goal "to increase the percent of residents who before and after surveys of parents and children in the
can reasonably get to work by public transit." Of course the people neighborhood
who will reside or work in the new development will be interested in
their accessibility to public transit too, but that is not the Hazard rating of streets in the neighborhood of a
motivation behind this measurement. proposed development can again be made by traffic

Public and Private Services 83

engineers and police based on expected changes in traffic overall citizen satisfaction with local shopping as affected
volumes, types of traffic (such as trucks), signals or signs, by development. These measures are intended primarily for
sightlines, and other factors. Neighborhood perceptions of residential neighborhoods but may be applied to shopping
the current hazard may be collected by citizen surveys as a conditions near work centers for the lunchtime and
baseline for estimating possible changes. If citizens feel very after-workday buyers.
safe today when there is low traffic and the likely volume
will increase sharply, educated guesses as to changes in
perceptions can be made. It is probably not reliable to use Accessibility
the survey to elicit citizens opinions on what their Data on accessibility should be' collected to show the
perceptions will be after development, except perhaps when approximate change in the number of people who can get
extreme changes in conditions are expected. to major types of stores or shopping centers within 5 to 15
minutes walking (one-eighth to one-half miles), within an
SHOPPING x-minute car ride or within a y-minute public transit ride.
These data, for both past and proposed develop-
Measure 37. Change in the number of stores and ments, can be estimated by plotting store locations and
services, by type, available within x distance of y population distributions before and after development on a
people. map, and using knowledge of local walking, driving, or
public transportation travel times. Large department stores
Measure 38. Change in the percent of people and chain stores often obtain such information and rnight
generally satisfied with local shopping conditions make it available. Of course, everyone does not patronize
(access, variety, crowdedness). the nearest stores, but assuming that most people do will
suffice for most impact analysis purposes.
Commercial developments may increase the number
and types of retail stores and alter the community's access Citizen Satisfaction
to shopping opportunities. Residential growth may crowd Perceptions of the overall adequacy of local shopping
existing stores with new customers and displace some
stores-though commercial facilities often expand to meet facilities can be collected by citizen surveys in the
additional demand. neighborhood of the development (preferably as part of
Most people want access t .o a variety of types of citizen surveys required for other measures). Overall percep-
stores, and a choice among stores of a given type. Stores tions will be difficult to project for proposed development.
also serve as casual meeting places and for other. social However, perceptions of the overall satisfaction with
purposes as well as for providing goods.22 existing shopping could be used as a basis for making
The suggested measures deal with accessibility and qualitative estimates of how expected changes in shopping
might affect the neighborhood. For example, if residents
consider shopping in current stores satisfactory, a proposed
22. For a general discussion of the role business establish- new supermarket requiring rezoning might have less merit
ments play in the social life of urban neighborhoods, see J. Jacobs,
77te Death and Life of Great American Cities, New York, Random than if current citizen perceptions were that shopping
House, 1969. conditions were completely adequate.

84 Data Sources and Analysis

V. HOUSING AND SOCIAL

CONDITIONS

Somewhat surprisingly, the impact of new residential 0 Outdoor activity patterns (such as playing,
development on community housing needs is not always sitting, walking and socializing) and their per-
considered in evaluating proposed developments. Often this ceived importance.
is because of the false assumption that natural market 0 Pedestrian accessibility to shopping, recreation,
actions balance supply.and demand. The private housing and schools.
market frequently fails as a provider of housing needs,
especially for families in the lower income ranges. Impact 0 Perceptions of neighborhood traffic hazards.
analyses should attempt to assess changes in the housing Feeling of security from crime.
supply, in terms of community housing needs. However,
housing should not be viewed, in assessing impact, only in Attitudes toward neighborhood-such as attrac-
terms of new or existing physical structures. Viewed more tiveness, friendliness, crowdedness, and overall
broadly, housing involves meeting certain needs and prefer- desirableness as a place to live or work.
ences for a large range of services. In this context, housing
is seen as a delivery system for these services. Some aspects of these factors have been discussed in
The effects of new housing on the price of existing sections on recreation, education, shopping, transportation
housing, and the impact on prices if new residential and aesthetics. This section emphasizes those considerations
development is constrained, should both also be considered. not previously discussed. But they all should be considered
Such price changes affect the ability of households to together to better understand likely neighborhood impacts.
obtain adequate housing or, if renting, even to stay in the It is difficult to predict how these social conditions
community. Techniques for estimating prices change effects may change over time. The state of the art is such that one
are still under development. can at most be confident in describing how people
But the area probably given least attention in most presently use and perceive of their neighborhood. By
evaluations is the impact of a development on neighbor- conducting before and after (retrospective) case studies of
hood social conditions-the interaction of people with one the impacts of developments on their neighborhoods and
another, the ways in which residents (and workers) use the comparative studies of "control" neighborhoods similar in
neighborhood, and their attitudes or perception of the terms of socioeconomic and demographic characteristic of
neighborhood as a place to live or work. residents and physical design aspects of housing structure or
The impact on social conditions should be assessed by layout, one can begin to develop a basis for estimating
considering the changes to a series of interrelated factors: changes in users' behaviors and attitudes likely to be
brought about by development. That is, given current status
� Displacement and relocation of existing resi- of a neighborhood and a repertory of case studies, one
dents and workers. might be able to make improved estimates of changes likely
to occur in neighborhood social conditions. Despite the
� Social interaction patterns and their perceived difficulty in doing these types of studies, these social issues
importance (by local residents and workers). are often at the heart of neighborhood concerns regarding

proposed developments, and they should be explicitly in them. "Substandard" must be defined explicitly in each
considered. community. The criteria may be serious violations of
These suggestions for measuring impacts on housing building or health codes or U.S. Census terminology
and social conditions are offered because these areas are so ("dilapidated or deteriorated" as defined in the 1960
crucial. But it is underscored that many of the measure- Census, or incomplete plumbing, as defined in 1970). Data
ment procedures discussed here for these areas represent on the number of substandard units to be removed and the
preliminary approaches that remain to be tested. totals remaining in the community are often known. If the
community has not kept independent records, the count of
HOUSING ADEQUACY substandard housing in the 1970 Census can be used as a
base. This inventory can be updated from cumulative
Measure 39. Change in number and percent of records of units razed, from sample data provided by
housing units that are substandard, and change in building, fire, and health inspectors, and from general
number and percent of people living in such units. knowledge of community conditions by welfare officials
and others.
Measure 40. Change in number and percent of Note that adding new housing units will auto-
housing units by type (price or rent range, zoning matically reduce the percentage of total units that are
category, owner-occupied and rental, etc.) relative substandard and the percentage of citizens living in them
to demand or to number of families in various without necessarily alleviating the existing problem at all.
income classes in the community. Therefore, the changes in absolute numbers as well as the
percentages are needed.
Residential development obviously affects the
housing stock in the community by providing now housing
units. Development of any kind may also change the Changes in Housing Mix
housing stock by destroying existing housing on the site. The description of housing stock mix should be
Commercial and industrial developments may affect hous- categorized by price, type, and ownership.
ing indirectly by their effect on jobs and the loc@d econ- PKce should be classified according to five to ten
omy, which in turn may alter housing demand, prices, rates sales price or annual rent level bands. Houses and con-
of abandonment, upkeep, and crowding. dominium apartments should be stated separately from
Housing objectives differ in many communities. Some rental units. All should be specified by number of bed-
that have undergone rapid recent growth are attempting to rooms (efficiency, 1, 2, 3, or more).
slow or stop new housing. Others, attempting to cash in on I Type of housing should distinguish among single-
growth, are promoting primary or vacation residences. Still family detached, townhouse, garden apartment, and high-
others are attempting to improve housing for low- and rise. Consideration should be given. to using finer
middle-income families, and some central cities are making distinctions such as lot size, and multifamily dwellings by
a special bid to attract the affluent number of apartment units contained.
Because of this diversity, communities must devise Ownership classifies dwellings as rented or owner-
their own sets of housing measures. The recommended occupied. Many believe that there is some relationship
measures simply aim to describe some fairly universal between ownership status and upkeep, neighborhood sta-
concerns-effects of new development on substandard bility, and community participation.
housing, changes in the mix of housing, and impact on It often may be desirable to present these categories
housing needs of existing residents. A community could of the housing mix by different areas or neighborhoods of
then convert these raw data into measures more closely the jurisdiction.
attuned to their desired housing mix or desired direction of The above measures can best be used to describe
change. Preferably, proposed changes in housing would be the instantaneous change in substandard housing and the
related quantitatively to community housing mix needs and variety of housing available after a particular development
objectives. If this is too complex in some circumstances, an occurs. The ultimate effect on the housing stock is more
alternative approach is to make ad hoc judgments on complex and is a function of the percent of new residents
whether the new mix is desirable. that transfer from within the community; whether the new
Changes in Substandard Housing residents are newly created family units; who (if anyone)
fills their vacated residences, and so on down the price
A goal of most communities is the elimination of chain. What happens at the end of this chain-e.g., an
substandard housing. Measure 39 indicates the absolute and abandoned unit, a unit sharply decreased in value, a stable
percentage changes in substandard units and in people living low-priced home-will determine the long-range changes in

86 Data Sources and Analysis

the housing mix and total housing stock in the community. represent a high proportion of those who pay a higher-
It may take some time for this chain to work itself out.' than-average share of current income for housing because
For past and proposed developments, data on the savings and household size play a major role in determining
-number and type of units added or torn down by the what housing people can afford. College students, with
development are almost always available. These can be little or no income, also represent a special case. Thus it
added to the housing mix data before construction to would be more realistic to develop different income-to-
determining the immediate changes. Most of the desired housing-price norms for at least different age groups and
baseline data need only be approximate to give an adequate different household sizes.
idea of how the development will influence the major HUD FHA demand estimates from the "Analysis of
characteristics of the mix. Housing price data can be based Housing Market" series present further guidance about
on current sales prices from information collected by estimated housing demand by price range and county in
3
realtors. In the absence of such data, assessment records can metropolitan areas. The statistics are based on existing
be used, adjusting the data by the use of asse sse d-to -market- intracommunity income characteristics rather than housing
value ratios based on state or federal studies available for needs of inmigrants. For example, only 6 percent of the
larger communities and counties. Planning departments housing demand in one affluent county is for units under
usually have data on the number of housing units by type $30,000, while an adjacent county is cited as needing 31
or zoning category. Market research studies by area realtors percent of its units in this price range. 4 These reports,
and businesses are other potential sources of data on issued for large SMSA's primarily to identify housing needs
housing prices, types, and styles. Ownership status can be for lower income groups, also provide estimates of demand
determined from sampling property tax records. for rental units by rent level.and number of bedrooms.
Further insight into housing needs may be obtained
Estimating Housing Needs by determining occupancy rates for various types and prices
At present, there does not seem to be any completely of standard h .ousing. Low occupancy rates for a particular
satisfactory approach to identifying community housing type-assuming the features and neighborhood are accept-
needs quantitatively. Several interim approaches may be able-would raise questions if more housing of this type
considered while awaiting development of better methods were proposed. High occupancy rates, say above 95
still in research. percent, might suggest that more stock may be needed to
One means of estimating housing need is to relate the meet demand or to at least make the market more fluid.
current costs of housing and local income distribution Note that low occupancy rates may be due to undesirable
patterns to some norm. For example, the average American features of the unoccupied housing or its neighborhood,
family, based on Department of Labor statistics, allocates and not because demand is being satisfied.
17 to 22 percent of income to housing, varying by Areawide housing market models, 5such as one cur-
ownership status and income level. The degree to which a rently under development by deLeeuw, should make it
community has a reasonable match between rent levels, possible to improve estimates of housing demand and the
home values and income provides a rough reflection of how effect of development on demand, but these models are still
well supply meets need. The 1970 Census provides data on in the research stage.
the proportion of owner-occupied units by value and the
proportion of rental units by monthly rents. These would PEOPLE DISPLACED
have to be sharply adjusted for cost-of-living changes since
2 Measure 41. Number of residents or workers
then. However, there are many problems with simply displaced by development-and whether they are
linking housing need to income. Households of similar satisfied with having to move.
income but different demographic characteristics do not Development may uproot current residents by physi-
have the same needs. For example, persons over 65 cally displacing their homes. Less obviously, development
may cause people to move because of its effect on taxes or
on the physical or social environment.
1. A discussion of the housing chain as it affects the poor 3. For example, Department of Housing and Urban Develop-
may be found in John B. Lansing, Charles Wade Clifton, and James
N. Morgan, New Homes and Poor People, A Study of Chains of ment, Analysis of the Washington, D.C., Housing Market, Washing-
Moves, Survey Research Center, Institute for Social Research, ton, D.C., 1972.
University of Michigan, Maxwell Printing, 1969. 4. Ibid, Department of Housing and Urban Development.

2. Related issues, not further discussed in this paper, are the 5. Frank deLeeuw, Raymond Struyk, Sue Marshall, Urban
effects that new construction, or constraints placed on new Institute Housing Model: Second Year Report, Washington, D.C.,
development, have on the cost of housing. The Urban Institute, 1973.

Housing and Social Conditions 87

Development can also displace workers by removing have any explicit policy other than equal opportunity. If a
existing stores and other enterprises. When certain jobs are policy exists, individual attitudes or neighborhood objec-
eliminated and not moved to a convenient new location or tives may differ drastically from it. One way or another,
substituted for by new jobs in the development, the net loss most people care about how development will affect the
of employment could cause some people to leave the population mix in their neighborhood as well as at the
jurisdiction entirely. community level.
At a minimum, the number of residents and workers
who will be displaced by a development should be reported. For past development, the census provides most of
Preferably, data should show whether those displaced are the data needed to identifv the people ?nix in the
satisfied with the prospect of moving, whether they are to community and in particular neighborhoods (though the
be compensated, how many may be given temporary latter neighborhood estimates especially may have to be
quarters (and for how long), the percent expected to return updated because they can change sharply over a few years.)
to improved conditions as a result of the development, and A survey of neighborhood residents and workers could be
the number of people leaving the community after develop- used to identify socioeconomic and demographic character-
ment (and their reasons for so doing). istics of the households and work force both before and
For past developments, the number of people directly after the development in the neighborhood and nearby
displaced can be estimated from a knowledge of the areas. 6Further estimates of the population mix may be
housing or commercial units torn down and their occu- obtained from data provided by local schools, churches,
pancy rates, if not known precisely. Census and other data ethnic association, and realtors. Changes in the people mix
on the number of occupants per unit may be used. nose due to development should be distinguished from general
displaced can be surveyed to see if they left willingly, and a changes due to population shifts that are occurring in the
sample of people who chose to leave the adjacent neighbor- city, metropolitan area, region, and nation.
hood can be surveyed to determine if the cause was
development related. For proposed developments, estimates of changes in
For proposed developments, basically the same pro- the people mix can be based on expected characteristics of
cedure applies, except that surveys of people planning to the people likely to buy or rent at various@price ranges,
leave the neighborhood (apart from those displaced) would coupled with a detailed knowledge of community housing
be difficult to carry out and interpret. Instead, possible conditions, preferences, and trends. (These estimates are
changes in property taxes (which can be estimated from also needed for developing fiscal impact, recreation, educa-
fiscal data discussed earlier) could be used to determine the tion and other measures.)
increase in housing costs-at least the tax portion for people
in different house price ranges. Making simple assumptions
about family incomes for different house price ranges, and
using simple rules of thumb, such as no more than 25 CROWDEDNESS
percent of income should be spent on housing, a rough
estimate of the number of families near or over the Measure 43. Change in the percent of people who
borderline can be made. This will indicate the approximate perceive their neighborhood as too crowded.
number of families who can no longer afford to live in the
community. Of course, the sacrifice people may wish to
make to stay, the cost of moving, and a host of other Some aspects of crowdedness are reflected in the
factors will determine whether people actually do move. measures for transportation, recreation, education, and
The percent of people who will leave for social or physical shopping, and in the capacity measures discussed in Part 1,
environmental reasons may be crudely and cautiously Chapter 1, and illustrated in Exhibit 5.
estimated from past case histories of similar physical and Population density is often used in planning and
socioeconomical changes in neighborhoods. zoning matters as a measure of crowdedness. If density is
used as a measure, attention should be paid not only to
POPULATION MIX residential density but also to the density at various times
of day and days of week. However, even at a given high
Measure 42. Change in the population distribution
by age, income, religion, racial or ethnic group, 6, This survey could be the background data collected as
occupational class, and household type. part of a more general survey that would seek to identify citizen
perceptions of privacy, crowdedness, friendliness, and other neigh-
Some communities may wish to encourage a diversity borhood conditions as part of other measures that have been
of people within the community. Some may prefer not to suggested elsewhere in this report.

[Parggraphs in italics deal with retrospective analyses]
88 Data Sources and Analysis

density, the likelihood that people will feel crowded may barriers such as fences, buildings, and traffic hazards) and
vary a great deal depending on the arrangement of space, the socioeconomic homogeneity of the neighborhood.*7
the adequacy of services, and personal living styles.
Therefore, in addition to raw population densities, a Data Collection for Past Development
direct measure of individuals' overall perceptions of com-
munity crowdedness is desirable to capture impressions that Ae degree to which new development affected the
may not be adequately reflected by any of the above sociability or friendliness of a neighborhood may be
measures. Surveys to determine perceptions may also probe measured by the changes in (a) the frequency of visits
among people in the vicinity of a development; (b) the
specific elements of crowding that may be especially number of friendships and frequency of visits between
annoying, such as too many people on the streets, traffic
jams, crowding at local informal or formal recreational people in the existing neighborhood and the new develop-
centers, and so forth. Information on the number of ment; and (c) the percent of people perceiving changes in
persons per room and in the building of each household the degree offiriendliness.
surveyed should be collected to help indicate if the Measure (a) reflects the degree to which people in the
perceived crowding reflects primarily the crowdedness of a vicinity of the development-but not in it or uprooted by
person's residence, of streets and service facilities, or both. it-have their friendships affected by the development. For
(The questions on crowdedness could be part of a survey to a given person, the change in frequency of visiting would be
collect data for the various perception measures suggested expressed in terms of number of visits per month with
throughout this report.) ffiends within a given distance of the development (eg., a
The expected perception of crowdedness by the 10-minute walk). Friends who are no longer visited because
community surrounding a proposed development might of displacement would be noted Visiting which is con-
eventually be estimated from correlations of past surveys tinued using a change in travel modes (driving instead of
with estimates of the change in population density, waiting walking) would still be counted as visits. Reasons for
times in local facilities, percent of capacity of local observed changes in sociability should be noted to estimate
facilities, neighborhood open space, increased traffic the degree to which they are affected by development-
volumes, and other elements, but this is beyond the current related changes in travel convenience or intangibles such as
state of the art. At present, qualitative estimates based on neighborhood ambience, as opposed to strictly personal
judgment of the effects of changes in these contributing reasons.
elements of crowdedness, and by analogy with past cases, Measure (b) reflects the degree to which the new
will have to suffice. development is socially integrated into the neighborhood,
and the degree to which new friendships may replace old
friendships.
Measure (c) would reflect citizen perception of
SOCIABI LITY/FR I ENDLIN ESS factors such as the ease of makingfriends, the amiability in
stranger-to-stranger contacts, and the number of people
Measure 44. Change in frequency of visits to known by sight. This is complementary to the perception
friends among people in the existing neighborhood, of privacy, crowdedness, and overall neighborhood rating
and frequency of visits between people in the sought in other measures.
existing neighborhood and the new development. ne main tool for collecting data for all these
measurements could be a survey of citizens in the neighbor-
Measure 45. Change in percent of people per- hood of the development before and after development.8
ceiving their neighborhood as friendly. Direct observations of how, when and where people
socialize outdoors are also important to supplement the
survey data.
While certain individuals and families seem to prefer
living anonymously and in isolation, at - least from the
people@ in their immediate neighborhood, many people 7. For further discussion of factors influencing sociability,
consider it important to live in a community where they see A.L. Schorr, "Housing and Its Effects," in H.M. Proshansky,
can establish and maintain friendships. Some people also W.H. Ittelson, and L.G. Rivlin, eds., Environmental Psychology,
prefer a community that is generally characterized as being New York, Holt, Rinehart and Winston, 1970, pp. 319-33,
friendly and warm. 8. For some sample questions that might be used in a
Development may affect both of these aspects of sociability survey, and an effective format for presenting the results,
see D. Appleyard and M. Lintell, "The Environmental Quality of
sociability by changing the physical proximity of people, City Streets: The Resident's Viewpoint," American Institute of
the ease of movement (by creating or removing physical Planners Journal, March 1972, pp. 84-101.

Housing and Social Conditions 89

Data Collection for Proposed Development loss in privacy before and after development would take
Quantitative estimates of changes in sociability as a into account elements such as whether people are minding
result of a proposed development are not likely to be their own business as well as physical changes that affect
reliable, given the present state of knowledge. Probably the privacy.
best that can be done is to make qualitative estimates of the Sightlines for a proposed development can be deter-
likely direction and degree of change based on analogies to mined from plans, photos, and maps of the area. Pedestrian
comparable past examples within the community or similar traffic past various residences can be estimated from the
communities, and on expected changes in factors such as number of people who will be added to the neighborhood
physical barriers, the size of the development, the number and their likely walking destinations. The overall impact of
of people to be uprooted, the likely homogeneity between citizens' perceptions of privacy can probably best be
the existing and new socioeconomic distributions, and estimated from experience with roughly comparable past
whether the neighborhood of the development is to be situations. As with other measures of perceptions, a good
peopled with transient or long-term residents. As a base starting point is to identify the current neighborhood
from which to make judgments, citizen surveys and direct perception of privacy, which then bounds the changes that
observations can be used to estimate the current pre- are possible.
development sociability in the neighborhood. OVERALL CONTENTMENT WITH
PRIVACY NEIGHBORHOOD
Measure 46. Number and percent of people with Measure 48. Change in percent of people who
change in "visual" or "auditory" privacy. perceive their community as a good place to live.
The overall impact of a development on how people
Measure 47. Number and percent of people regard their community can be reflected by various direct
perceiving a loss in privacy. and indirect measures. Data should be collected on the
Developments may affect "visual" privacy by pro- extent to which residents perceive the community as a good
viding new sightlines into peoples' backyards and windows place to live and on changes in lengths of residency.9
and they may affect "auditory" privacy by placing addi- Direct surveys are one of the better devices for
tional people within earshot. They may also increase determining how people feel about their neighborhood. The
privacy by providing visual or sound screenings where none maintenance level of private homes and lawns and the types
existed., A big factor may be changes in the amount of of social behavior exhibited in public may yield some
pedestrian or vehicular traffic past residences. Privacy may further insights. Interpreting such indirect observations or
also be increased or decreased by more subtle changes such measures poses serious problems, so they probably should
as the life styles of people who join the community. not be used alone.
Visual privacy can often be restored by defensive For retrospective analyses, surveys may be taken
mechanisms such as pulling shades, building fences, and before and after development. Probing questions will be
adding shrubbery, though the sense of privacy loss may necessary to seek reasons that people are satisfied or
remain. Auditory privacy is more difficult to remedy, dissatisfied and to determine if changes during the time
though barriers or soundproofing may help. period are probably related to the development.
Both objective measures of changes in sightlines and Determining the impact of a proposed development
physical arrangements that affect how easy it is to hear or on resident satisfaction can only be estimated by judgment
see personal activities, and subjective measures of peoples' based on past case histories and knowledge of the neighbor-
perceptions of their change in privacy can be used. hood until much more is known on how development
In collecting objective data on loss of privacy, affects the total environment, and how people's overall
distinctions should be made between major intrusions, such attitudes are affected by changes in the various elements.
as the first new budding that lets other people look into the Surveys and regard to concerns expressed by citizens at
windows, yard, or the roof garden of an existing building, hearings about development can help officials understand
and minor intrusions which are not the first of a kind. what people currently like or dislike about their neighbor-
Evaluation of the impact on privacy of a past hoods and about growth patterns. These insights can then
development can be based on visits to the development and help form a basis for judgmental estimates about future
knowledge of the sightlines from previous buildings on the satisfaction or discontent.
development site, using maps, plans, or photos of the area. 9. An attempt should be made to distinguish between
Changes in pedestrian traffic before and after development changes in residency resulting from increases in housing costs or
employment shifts and those resulting more directly, from the
are readily measurable. A survey of citizen perceptions of development in question.

90 Data Sources and Analysis

APPENDIX

OTHER IMPACT MEASURES CONSIDERED

In addition to the measures presented in Exhibit 1, a effect will be through jobs and will be indirectly reflected
number of others were considered but deemed less suitable by the employment measures (2-3) in Exhibit 1.
for immediate widespread use for a variety of reasons, such
as their apparent lesser importance or their data collection Change in Utility Costs
difficulties.
Some of these other measures are presented in Telephone, electric, gas, and water utility rates may
Exhibit 7 and are discussed in the following pages. For be subject to economies or diseconomies of scale. Costs to
certain communities, some of these may be as important as the consumer may, therefore, change as a function of
those in the main body. Matters concerning the micro- development. In addition, developments that are remote or
climate around tall buildings are considered especially cause special service problems may lead to the shifting of
important in the San Francisco area, for example. Also, to these additional utility costs to all residents instead of
mention briefly some alternative issues underscores the higher costs for just those enjoying the benefits. Data may
earlier point that community judgments of what is impor- be obtainable from utility companies in some cases, but
tant locally should influence the compilation of the list of cost attribution is complex.
measures to be used.
Change in Available Agricultural and
Financial Stability of Developer Commercial Forest Land

In approving developments, the fiscal soundness of Although changes in agricultural lands are more often
the developer should be considered, perhaps as part of the concerns at regional or state levels, some local governments
preliminary review of a developer's initial application. If a may also wish to keep track of how their agricultural and
builder goes bankrupt during the construction phase, forest resources are affected by the encroachments of
structures can remain incomplete and become eyesores development, especially where such special purpose or
during the period of litigation. The jurisdiction may incur prime land is a central feature of the local economy.
expenses, such as the provision of roads and sewers, but fail
to receive anticipated payment from the builder or resi- Change in Microclimate
dents. And the potential residents of the development may The sunshine, wind, and temperature of a street can
lose some or all of their investment. be affected by the development along it. Rows of tall
buildings lining a street affect sun exposure and create a
Change in Personal Income Per Household canyon effect that may drastically change winds and air
Interesting as this information would be, the impact pollution conditions.
of an individual development on income for most existing Land Pollution
households is likely to be small and difficult to estimate.
Incomes of new persons in the new development can be In some communities such as New York City, dog
estimated, but the primary and secondary effects of their excrement has become a problem on sidewalks and in
spending on other people's incomes require many assump- playgrounds and parks. In Washington, D.C., the iead
tions and are unlikely to result in reliable or useful content of inner-city soil has increased due to traffic and is
findings. For commercial development the most direct thought to be a health hazard because of its ingestion by

EXHIBIT 7

OTHER IMPACT MEASURES CONSIDERED

Impact Area Measure

Local Economy Financial stability of developer.

Change in personal income per household.

Change in utility costs.

Natural Environment Change in available agricultural or commercial
forest land.

Change in microclimate.

Land pollution.

Services Storm drainage quality.

Additional measures of changes in the
quality of local government services.

Health and Safety Changes in death and illness rates.

Level of hazard to workers and public
during construction.

Level of structural safety.

Local Transportation Change in car trips or car miles per person
per day.

Social Conditions Consumer protection measures.

Neighborhood stability -change in
tenure rates.

92 Measuring Impacts of Development

children. Developments can have an impact on these inadequate, the safety features would be an important
problems as well as more traditional soil problems such as measure in the evaluation.
salinity, chemical imbalance, erosion, and pollution of
ground water. Change in Car Trips or Car Miles
Storm Drainage Quality Per Person Per Day
Extremely poor storm drainage in a development will This measure might be considered an indicator of
affect the frequency of flooding and is, therefore, dealt how the development affects people's dependence on cars.
with in Measure 12 of Exhibit 1. However, less drastic A growing number of people wish to reduce their depend-
effects of inadequate storm drainage-such as minor ence on cars, something that many planners have long felt
flooding of streets, gutters, and lawns-still have nuisance would make for better cities. Even the "cleaner" cars now
being engineered will still create problems of congestion,
and negative aesthetic value and may also be considered. safety, and energy consumption. The measure might be
Many building codes provide drainage controls, but where applied to (a) people in the development, considering their
these codes are lacking, a special measure may be useful, average miles per day before and after living in the
especially for protecting areas adjacent to new develop- development, and (b) people in the community, especially
ment. where a commercial or industrial development affects work
Additional Measures of Changes in the and shopping proximity to residences. It might be espe-
Quality of Local Government Services cially useful to determine the trend in dependence on cars
over time.
Development may affect solid waste collection, street
cleanliness, and other public services besides those reflected
in the main list. Whenever it appears that a new develop- Consumer Protection Measures
ment iriight impair the quality of local government services Measures in Exhibit I do not include the amenities or
not covered by the main list of impact measures, appro- quality that the buyer or renter of a development gets for
priate additional measures should be added to the list. his money, though some important aspects of consumer
protection, however, are included in measures dealing with
Changes in Death and Illness Rates health and safety, crime, fire, natural disaster, drinking
New developments can affect community health by water, and pollution. It might also be pertinent in evaluat-
their impacts on pollution, housing, sanitation, and drink- ing whether a development should proceed to check the
ing water conditions; by the health, hygiene, and age developer's record for fair dealing. A particularly bad
distribution of the people they attract; and by their record in this respect might be grounds for disallowing
influence on psychological stresses. The synergistic effects further development by him in the community.
of these elements on death and illness rates are important
but are not feasible to estimate with current knowledge. Neighborhood Stability-Change
Level of Hazard to Workers and in Tenure Rates
Public During Construction Preserving the stability of a neighborhood is an
Construction safety is regulated by many local codes, oft-expressed objective of residents. It usually implies a
but the likelihood of any hazards other than the usual ones desire to have people around long enough to have lasting
would merit special attention. friendships or many acquaintances, or to have people in the
community who will care about it, and maintain it.
Level of Structural Safety However, sheer length of tenure is not an end in itself and
many factors in society outside the neighborhood or
The assumption behind the measures in Exhibit I is community encourage mobility. It is believed that measures
that building codes adequately provide for monitoring the in Exhibit I dealing with satisfaction with the community
structural safety and suitability of the soil for most will come close to telling most communities what they need
developments. Where the codes do not exist or are to know about stability.

Other Impact Measures Considered 93

THE URBAN INSTITUTE BOARD OF TRUSTEES
ROBERTS. McNAMARA, Chairman
President, International Bank for Reconstruction and
Development, Washington, D.C.
WILLIAM SCRANTON, Vice Chairman
Scranton, Pa.
JEAN FAIRFAX, Director, Division of Legal Information and
Community Service, NAACP Legal Defense and
Educational Fund, Inc., New York, N.Y.
EUGENE G. FUBINI, Consultant, Arlington, Va.
WILLIAM GORHAM, President, The Urban Institute,
Washington, D.C.
KATHARINE GRAHAM, Chairman of the Board,
Washington Post Co., Washington, D.C.
ROBERT V. HANSBERGER, Chairman and Chief Executive,
Futura Industries Corporation, Boise, Idaho
VERNON E. JORDAN, Executive Director, National Urban
League, Inc., New York, N.Y.
EDWARD HIRSCH LEVI, President, University of Chicago,
Chicago, 111.
RICHARD LLEWELYN-DAVIES,,President, Llewelyn-Daviles
Associates, New York, N.Y., and London, England
BAYLESS A. MANNING, President, Council on Foreign
Relations, New York, N.Y.
STANLEY MARCUS, President, Neiman-Marcus, Dallas, Tex.
ARJAY MILLER, Dean, Graduate School of Business,
Stanford University, Stanford, Calif.
J. IRWIN MILLER, Chairman, Cummins Engine Co., Inc.,
Columbus, Ind.
JOHN D. ROCKEFELLER IV, President, West Virginia
Wesleyan College, Buckhannon, W. Va.
WILLIAM D. RUCKELSHAUS, Ruckelshaus, Beveridge &
Fairbanks, Washington, D.C.
HERBERT SCARF, Professor of Economics, Yale University,
New Haven, Conn.
CHARLES L. SCHULTZE, Senior Fellow, Brookings
Institution, Washington, D.C.
FRANKLIN A. THOMAS, President, Bedford-Stuyvesant
Restoration Corp., New York, N.Y.
CYRUS R. VANCE, Partner, Simpson, Thacher & Bartlett,
New York, N.Y.
JOHN G. VENEMAN, President, Veneman Associates,
San Francisco, Calif.
JAMES VORENBERG, Professor, School of Law, Harvard
University, Cambridge, Mass.