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*Massachusetts Coastal Zone Management MASSACHUSETTS COASTAL SUBMERGENCE PROGRAM Passive Retreat of Massachusetts Coastal Upland Due to Relative Sea-Level Rise Commonwealth of Massachusetts Michael S. Dukakis, Governor - ive Office of Environmental Affairs ;,Hoyte, Secretary GE !chusetts Coastal Zone Management 4 59.4 i F. Delaney, Director .G5 1 987 PASSIVE RETREAT OF MASSACHUSETTS COASTAL UPLAND DUE TO RELATIVE SEA-LEVEL RISE by G.S. Giese, D.G. Aubrey and P. Zeeb Woods Hole Oceanographic Institution Woods Hole, MA 02543 I I lU.S. DEPARTMENT OF COMMERCE NOAA COASTAL SERVICES CENTER I ~~~~~~~~2234 SOUTH HOBSON AVENUE CHARLESTON, SC 29405-2413 I I ~I alhroj~newLPy ot Co o <b'ay I The preparation of this document was funded by the Office of Ocean and Coastal Resources Management, National Oceanic and Atmospheric Administration, U.S. Department of Commerce, under a program implementation grant to the Commonwealth of Massachusetts. i � gPUBLICATION: .,, mApproved by the State Purchasing Agent S 300-5-87-815491 Estimated Cost Per Copy $19.33 It 3 ~~~PASSIVE RETREAT OF MASSACHUSETTS COASTAL UPLAND DUE TO RELATIVE SEA-LEVEL RISE INTRODUCTION Shoreline recession is recognized widely as a major environmental management issue in 3 ~~~Massachusetts as well as in many other parts of the United States and throughout the world (Bird, 1976). In considering this issue, it is essential to separate the retreat of coastal upland areas from the retreat of wetlands because of the differences between the processes involved. The retreat of a barrier beach, for example, may involve the landward translation of an entire feature without diminution in its size, but upland retreat always results in the loss of upland area. Although upland I ~~~loss usually is accompanied by wetland gain, the upland lost is an irreversible loss of that area from those land uses for which wetlands are considered unfit. In Massachusetts these uses include, for 3 ~~~example, human habitation, transportation and commerce. Coastal upland retreat takes two distinct forms: active wave-produced erosion and passive loss resulting from relative sea-level rise. While a rise in relative sea level contributes to active wave-produced erosion, it is not possible at present to quantify the contribution to erosion made by sea-level rise. On the other hand, the recession of a passive shoreline as sea level rises can be estimated with reasonable accuracy. Unfortunately, estimates of passive shoreline recession are seldom available, probably I ~ ~~because upland loss due to this cause generally is considered to be small compared to that due to erosion. Relative sea-level rise along the Massachusetts coast over the past 40 years ranges between 3 ~~~2 and 3 mmn. per year (Aubrey and Emery, 1983). Within recent years, however, a rapidly increasing body of data has appeared in support of the hypothesis that global climatic warming 3 ~~~within the next century will cause increasing global sea level rises that can not be ignored. Hoffman (1984), for example, has projected global sea-level rises by the year 2100 ranging from 1.8 ft. ("low scenario") to 11.3 ft. ("high scenario"). Some emphasis in this report is placed on relative sea-level rise rather than absolute sea-level rise. Coastal submergence results not only from rise of ocean levels, but also from sinking of the I ~~~land. In Massachusetts, nearly two-thirds of the submergence during the past century (documented by tide-gauge data) results from subsidence of the land. Only one-third of the submergence appears to be due to ocean rise (Aubrey and Emery, 1983; Braatz and Aubrey, in press). In quantitative terms, over the past sixty years Massachusetts has been sinking at a rate of 1.9 mm/yr (0.0062 ft/yr) while the ocean has been rising at I mm/yr (0.003 Wtyk) on average. The estimates of magnitude of sea-level rise provided by Roffman (1984) do not include the effect of land sinking. If the higher rate of rise scenarios (averaging 28 mnm/yr) prove correct, the impact of land submergence is important only in the short term (the next 20-30 years). If the lowest rate-of-rise scenarios prove correct, however, then land subsidence will be a large fraction of the magnitude of sea-level rise (2 mm/yr versus 4-6 mnu/yr). The calculations based on hypsometric curves in the present study include the effect of landI submergence but the color-coded maps do not. The reader should be aware of this continental submergence, however, particularly if the low sea-level rise scenario is assumed to be true. Since3 the management implications for a lower rate of relative sea-level rise are less stringent than for the higher scenarios, the explicit neglect of land motions on the color-coded maps is justified.I The study reported here was designed to quantify the passive retreat of upland within the coastal communities of Massachusetts due to relative sea-level rise. The losses that presently occur annually, and those that will occur by the year 2025 given three specified projections of future relative sea-level rise, are presented for each community. Also presented are data that provide the means for predicting the rates and cumulative amounts of land area losses due to passive retreat that these communities will suffer in the future given any specified future relative sea-level rise or tidal range change scenario. Finally, color-coded. maps are presented for the harbors of Hyannis,3 Westport and Gloucester that display the areas that would be lost by the year 2100 given any one of four different sea-level rise scenarios. An appendix contains tables, graphs and figures that present the results of the study. A detailed description of the data analysis methodology also is included in the appendix.u The three sea-level rise scenarios presented here illustrate the potential magnitude of coastal -flooding from global climate warming. These scenarios are based on predictions containing significant uncertainties, given the lack of precise understanding of complex atmosheric chemical exchanges, ocean/atmosphere interactions, and effects of land albedo, for example. Consequently, the three scenarios presented are not necessarily the most probable sea-level rise scenarios; however they are commonly cited scenarios widely thought to approximate the range of possible impacts. One advantage of the hypsorneti-ic data is the ease with which updated scenarios can be applied to a3 coastal town to obtain a first-order quantification of impacts on that town. Application of the results of this study to coastal zone management and policy is fraught with theoretical and practical questions. How might the Commonwealth, a coastal county, or a coastal town respond to these results, and incorporate them into a managment scheme? With the 2 considerable uncertainty in the scientific basis for predicting the details of global warming, how can I ~ ~these uncertainties be translated into an equitable planning or zoning process? That a global warming is in process and will continue is incontrovertible. What are not known precisely are the U ~ ~~magnitude and timing of this global warming, and its exact impact on sea levels. The appropriate response to these issues and results on local and state-wide levels is one of 3 ~~increasing awareness. Legislation and re-zoning may be premature. However, awareness by town planners, politicians, and Conservation Commissions, for instance, must be increased. Long-range planning could take these shoreline retreat data into account when making major land use decisions. Conservation Commissions could err on the side of caution in a coastal construction issue, mandating pile foundations in areas of critical concern. Public works could incorporate these data in siting wells or new sewer systems. In summary, some rational response to these sea-level rise issues are appropriate at this time. Major legislation and drastic changes in regulations, N ~~however, may be premature and might better await a clearer consensus from the scientific community before enactment. * ~~~~Users of the data presented in this report must be aware that passive shoreline retreat via inundation is not the sole effect arising from global warming to which coastal communities must respond. Although the present study considers only the effect of passive retreat due to inundation, other impacts may be equally important. For example, rising sea levels will change the base level for river drainage and groundwater flow. Water quality deterioration may result from this impact. In addition, global warming will raise the ocean surface temperature, increasing the size of the "warm-pool" of water that is responsible for generating tropical cyclones. Although difficult to I ~~~predict in detail because of the complexities of non-linear atmospheric physics, this ocean warming is certain to alter storm climates along the eastern seaboard and elsewhere. If the net product is an increase in tropical cyclones reaching the northeast, this could result in more severe short-term (order of decades) economic impact than that due to simple passive retreat. While the present study investigates an issue of fundamental importance, the user should be aware of these other significant impacts, and plan their rational response to global warming accordingly. * ~~~~~~~METHODS Quantification of the passive retreat of coastal upland presents special problems due to the 3 ~~~peculiar "fractal" nature of the passive shoreline (Mandelbrot, 1977). Simply stated, the problem is that the complex form of the passive shoreline does not simplify as smaller and smaller segments 3 ~~~are examined, and thus the "tangible" shoreline always remains just out of reach of the investigator who would measure it. In order to skirt this problem, the present study deals not with the linear retreat of the shoreline, but rather with the areas that are lost as the shoreline recedes. Two separate approaches are used, each having special advantages and disadvantages. In the first, which treats entire coastal communities, the distribution of the area of the community with respect to its I ~~elevation is presented in the form of "hypsometric" curves, or cumulative frequency diagrams. I ~~~~~~~~~~~~~~3 While this is a powerful tool for the analysis of such geographical units as a whole, the results give no information about the change at a specific point within that unit. The second approach makes use of color-coded maps of areas that are of special concern for the management of ports and harbors. For this purpose the harbors of Hyannis, Westport and Gloucester were chosen. While it is difficult to quantify the effects of small changes from these color-coded maps, the areas that will (and will not) be affected are displayed clearly. Hypsometrv As a tool for calculating the retreat of coastal upland resulting from relative sea-level rise, hypsometry has been discussed by Giese et al. (1985). Unlike previous work, however, the present study makes use of digital elevation data that permits the application of the hypsometric method to large areas. A separate hypsometric curve was calculated for each of 72 Massachusetts coastal communities. The initial data for the upland hypsometric calculations were obtained from the U.S. Geological Survey's (USGS) National Cartographic Information Center (NCIC). They consist of two separate types of digital information, both of which are stored on magnetic tapes. The first type is elevation data that consists of land surface elevations to the nearest meter arranged in south-to-north profiles for entire one-degree latitude by one-degree longitude areas. The data points within the profiles, as well as the profiles themselves, are separated by intervals of three arc seconds, which is equivalent to a distance of about 92 m in a north-south direction and about 69 m in an east-west direction at a latitude of 42 degrees (the approximate mid-point of the study area). The second type of digital data consists of land use and land cover codes arranged in west-to-east rows aligned along a Universal Transverse Mercator (UTM) grid and covering entire one-degree latitude by two-degree longitude areas. The UTM coordinate system is rotated slightly counterclockwise with respect to the geographic latitude-longitude coordinate system. The land use and land cover code data points, and the rows containing them, are separated by intervals of 200 m. The land use codes include the U.S. Bureau of the Census designation for each 200 m square; these data permit the assignment of each square to a specific town or city. The land cover classification codes are sufficient to permit exclusion of wetland and inland water areas. A large part of the effort for this study consisted of the programming required to combine the raw digital data described above to produce a single data set consisting of elevation, census code and land-cover code for each 3-second box within one-degree blocks. A description of the programs and their use is included in Appendix B. During the study, the accuracy of the census and land-cover codes was checked by reference to the appropriate U.S.G.S. 7.5-minute series topographic maps, as well as by comparing the total calculated upland area of individual communities with the known value of their total land area. No problems were encountered with either type of code. Unfortunately, the same was not true of the elevation data. Initial tests of these data were performed by comparing profiles derived from the digital data to profiles based on the 7.5-minute series maps. The results of these tests generally 4 were satisfactory, particularly considering the fact that the entire elevation data set for each community was to be combined. However, when the cumulative distributions of elevation data were completed, it was evident that the USGS data were biased toward maxima in the vicinity of 3, 15, 30, 45 and higher multiples of 15 m. A program was written to smooth the distributions by redistributing the excessive values linearly to the depleted elevation categories between the maxima. A description of this procedure is included in Appendix B. The hypsometric curve thus calculated for one community (Barnstable) then was compared to the curve derived by a graphical method, and found to be acceptable. Nevertheless, it must be noted that cumulative hypsometric data presented in this report are less accurate than those that could be obtained using unbiased elevation data. Color-coded Mans The three maps that accompany this report were prepared to illustrate the effect upon three harbors of the relative sea-level rise predicted by four different scenarios for the year 2100. The harbors of Hyannis, Westport and Gloucester were chosen for this purpose because of their contrasting geological settings and because of their distribution along the Massachusetts coast. These maps were generated using data derived from the digitization of selected portions of the 7.5-minute series topographic maps for the three harbors. These maps have a contour interval of 10 feet, which is too great to resolve the flooding that was to be shown. Therefore, a surface was modelled to fit the digitized contours using a modified form of existing software. The levels of flooding characterizing the four scenarios then were applied to this modelled surface. Using color-plotting software and equipment, the flooded areas were displayed on color-coded maps. A detailed description of the methodology employed is included in Appendix B. The four sea-level rise scenarios illustrated on the maps were presented by Hoffman(1984), and produce flooding of 1.8, 4.7, 7.1 and 11.3 feet by the year 2100. These values were added to the NGVD elevations of the mean high water shorelines shown on the 7.5 minute series maps. The shoreline elevations were assumed equal to the half-tidal range at each particular harbor plus 0.5 ft to account for relative sea-level rise since 1929, the date of the NGVD datum. Local variations between NGVD and mean sea level were ignored, although these data are available. Two important differences between the hypsometric calculations and the color-coded maps should be noted. First, while the hyposometric calculations refer only to coastal uplands and wetland areas are entirely excluded, the color maps use as their basic reference level the present mean high water shoreline that, in many areas, borders on coastal wetlands. Therefore, the areas shown as being flooded according to the lowest rise scenario include wetland areas, many of which are salt marshes. The second difference, discussed in more detail below, is that the maps include a consideration of the ground water table rise that accompanies a rising relative sea level. This effect is excluded from the calculations based on hypsometry. 5 I u~--Upland I 00 yr. - - flood MHWS ___________ _______ MHW i.t~, ~ ~__--: .---_:_-.,+ MSL Fcats _o -MLW Figure I: Schematic of datum planes selected for sea-level rise scenarios. _m m m m ~n n m * ~~~~~~~RESULTS AND DISCUSSION The hypsometric curves for each community, together with tables giving the cumulative distribution of upland area with respect to elevation for each, are presented in Appendix A. The first area value presented in each table and graph (that for 3 mi) represents the upland area that lies between 2.5 and 3.5 m. This interval was chosen because at lower elevations it is impossible to distinguish between upland and wetland in the source data, and does not imply that there is no upland below 2.5 m. in the community. The assumption is made throughout this study that the areal frequency of upland below 2.5 m. is equal to that at 3 m. No assumption is made, however, about the elevations of the wetland/upland boundaries within the community, other than that these 3 ~~~boundaries, whatever their elevations, rise at the same rate as relative sea level (figure 1). It also should be noted that the data terminate at an elevation of 60 in., even when higher land exists within a community, in order to limit the size of the figures. There is a striking variation between communities in the shape of their hypsometric curves, reflecting variation in the geological processes that formed them. For example, communities on I ~~glacial outwash plains, such as Yarmouth, have curves with flatter slopes at low elevations as compared to those, such as Brewster, that lie on glacial moraines. Certain well-known local topographic features, such as the "Wellfleet Plains", also show up clearly on the figures. Making use of these hypsometric data, calculations have been made of the upland areas that 3 ~~each community would lose given particular changes in relative sea level. The results of these calculations are presented in Table 1. The first column in Table I lists the names of the coastal communities of Massachusetts, and the second column gives the upland area, in acres, of each community. The third column lists the percentage of upland area - and the fourth column the actual area measured in acres - that each community looses in response to a relative sea-level rise of 0.01 I ~~~ft. (3 mm), considered here to be the historical mean annual rate of rise (Aubrey and Emery, 1983). The following three pairs of columns give the amount of retreat, first in percent of total upland area 3 ~~and then in acres, that will occur between 1980 and 2025 given three different sea-level rise scenarios. The first scenario, case 1, calls for a continuation of the historical mean annual relative 3 ~~~sea-level rise rate of 0.01 ft/yr, giving a total rise of 0.45 ft over the 45 year period. Case 2 assumes that global sea level will rise 0.86 ft over the 45 year period (as given by Hoffman's "mid-range low" scenario) and that the local coastal subsidence rate will remain at 0.0062 ft/yr, I ~ ~~giving a total relative rise of 1. 14 ft by 2025. Case 3 is based on the same assumption about local subsidence, but uses Hoffman's "mid-range high" global sea-level rise estimate of 1.29 ft by 2025, 3 ~~~yielding a total relative rise of 1.57 ft. 'Be total Massachusetts upland loss at the historical relative sea-level rise rate is 65.4 acres 3 ~~per year. Averaged among the 72 communities, this works out to be 0.9 acres per year per community. However, the variation between communities is great, covering two orders of magnitude: Nantucket loses 6.1 acres per year, while Winthrop loses only 0.06 acres. After Nantucket, other communities having large annual losses are: Wareham, 4.7 acres; Falmouth, 3.8 I ~~~~~~~~~~~~~~7 TABLE 1 CALCULATED UPLAND RETREAT (Areas are in acres, % represents percent of upland submerged) HISTORICAL TOTAL RETREAT: 1980-2025 UPLAND ANNUAL RETREAT Case 1 Case 2 Case 3 AREA 0.01 ft/yr 0.45 ft 1.14 ft 1.57 ft RISE RISE RISE RISE TOWN NAME (ACRES) % AREA % AREA % AREA % AREA ACUSHNET 11520 0.002 0.22 0.09 9.8 0.22 25.0 0.30 34.4 AMESBURY 8052 0.002 0.13 0.07 5.8 0.18 14.7 0.25 20.2 BARNSTABLE 30709 0.012 3.72 0.54 167.2 1.38 423.6 1.90 583.4 BERKLEY 9582 0.005 0.43 0.20 19.4 0.51 49.2 0.71 67.7 BEVERLY 9748 0.003 0.28 0.13 12.7 0.33 32.2 0.46 44.4 BOSTON 24264 0.009 2.16 0.40 97.2 1.01 246.2 1.40 339.0 BOURNE 23935 0.006 1.53 0.29 68.9 0.73 174.6 1.00 240.5 BREWSTER 14110 0.005 0.72 0.23 32.4 0.58 82.0 0.80 113.0 CHATHAM 5250 0.020 1.04 0.89 46.8 2.26 118.5 3.11 163.2 CHELSEA 1217 0.010 0.12 0.44 5.4 1.12 13.6 1.54 18.7 CHILMARK 7196 0.007 0.50 0.32 22.7 0.80 57.4 1.10 79.1 COHASSET 3505 0.003 0.11 0.14 4.7 0.34 12.0 0.47 16.5 DANVERS 7866 0.003 0.25 0.14 11.3 0.36 28.7 0.50 39.5 DARTMOUTH 34785 0.006 2.05 0.27 92.4 0.67 234.0 0.93 322.2 DENNIS 10622 0.024 2.51 1.06 112.8 2.69 285.8 3.71 393.6 DIGHTON 13208 0.006 0.77 0.26 34.5 0.66 87.3 0.91 120.3 DUXBURY 12725 0.002 0.25 0.09 11.5 0.23 29.0 0.31 40.0 EASTHAM 6628 0.014 0.91 0.62 41.2 1.57 104.3 2.17 143.6 EDGARTOWN 9964 0.025 2.44 1.10 109.9 2.79 278.3 3.85 383.3 ESSEX 6227 0.003 0.22 0.16 9.8 0.40 24.8 0.55 34.2 EVERETT 1696 0.008 0.14 0.37 6.3 0.93 15.9 1.29 21.8 FAIRHAVEN 6765 0.020 1.35 0.90 60.9 2.28 154.2 3.14 212.4 FALL RIVER 20708 0.001 0.19 0.04 8.4 0.10 21.2 0.14 29.3 FALMOUTH 24340 0.016 3.82 0.71 172.0 1.79 435.6 2.46 600.0 FREETOWN 19862 0.002 0.34 0.08 15.2 0.19 38.5 0.27 53.0 GAY HEAD 1933 0.012 0.24 0.55 10.7 1.40 27.1 1.93 37.3 GLOUCESTER 15009 0.003 0.48 0.14 21.6 0.36 54.8 0.50 75.4 GOSNOLD 4327 0.013 0.58 0.60 26.1 1.53 66.1 2.10 91.0 HARWICH 11825 0.016 1.92 0.73 86.2 1.85 218.4 2.54 300.8 HINGHAM 8772 0.002 0.17 0.09 7.5 0.22 19.0 0.30 26.2 HULL 624 0.026 0.16 1.18 7.4 3.00 18.7 4.13 25.8 IPSWICH 14516 0.006 0.83 0.26 37.2 0.65 94.3 0.89 129.9 KINGSTON 11415 0.003 0.35 0.14 15.9 0.35 40.3 0.49 55.6 LYNN 6336 0.004 0.26 0.18 11.7 0.47 29.6 0.64 40.8 MANCHESTER 4793 0.002 0.12 0.11 5.2 0.27 13.1 0.38 18.1 MARBLEHEAD 2353 0.007 0.16 0.30 7.1 0.76 18.0 1.05 24.8 MARION 6883 0.031 2.13 1.39 96.0 3.53 243.2 4.87 335.0 MARSHFIELD 14332 0.004 0.60 0.19 27.1 0.48 68.6 0.66 94.5 MASHPEE 13386 0.010 1.35 0.45 60.8 1.15 154.1 1.59 212.3 MATTAPOISETT 5647 0.012 0.69 0.55 31.3 1.40 79.2 1.93 109.0 8 TABLE 1 (continued) CALCULATED UPLAND RETREAT (Areas are in acres, % represents percent of upland submerged) HISTORICAL TOTAL RETREAT: 1980-2025 UPLAND ANNUAL RETREAT Case 1 Case 2 Case 3 AREA 0.01 ft/yr 0.45 ft 1.14 ft 1.57 ft RISE RISE RISE RISE TOWN NAME (ACRES!) AREA % AREA % AREA % AREA NAHANT 465 0.019 0.09 0.83 3.9 2.11 9.8 2.90 13.5 NANTUCKET 23225 0.027 6.15 1.19 277.0 3.02 701.6 4.16 966.3 NEW BEDFORD 10410 0.006 0.60 0.26 27.2 0.66 68.8 0.91 94.8 NEWBURY 9442 0.009 0.81 0.39 36.5 0.98 92.6 1.35 127.5 NEWBURYPORT 4705 0.005 0.22 0.21 9.7 0.52 24.7 0.72 34.0 OAK BLUFFS 4288 0.014 0.59 0.62 26.4 1.56 67.0 2.15 92.2 ORLEANS 6211 0.017 1.07 0.78 48.4 1.97 122.7 2.72 168.7 PLYMOUTH 59264 0.001 0.77 0.06 34.7 0.15 87.8 0.20 121.0 PROVINCETOWN 1173 0.018 0.21 0.81 9.5 2.05 24.1 2.83 33.1 QUINCY 8062 0.010 0.84 0.47 37.7 1.19 95.6 1.63 131.6 REHOBOTH 27701 0.003 0.78 0.13 34.9 0.32 88.4 0.44 121.8 REVERE 2595 0.009 0.24 0.41 10.7 1.05 27.2 1.44 37.5 ROCKPORT 3715 0.004 0.14 0.18 6.5 0.44 16.5 0.61 22.7 ROWLEY 9184 0.002 0.17 0.08' 7.4 0.21 18.8 0.28 26.0 SALEM 3956 0.007 0.29 0.33 13.0 0.83 32.9 1.15 45.3 SALISBURY 6167 0.013 0.82 0.60 36.9 1.52 93.5 2.09 128.8 SANDWICH1 24469 0.005 1.20 0.22 54.0 0.56 136.7 0.77 188.2 SAUGUS 5859 0.002 0.13 0.10 6.1 0.26 15.4 0.36 21.2 SCITUATE 8745 0.004 0.38 0.20 17.3 0.50 43.9 0.69 60.4 SEEKONK 11433 0.001 0.09 0.04 4.1 0.09 10.4 0.13 14.4 SOMERSET 4184 0.011 0.46 0.50 20.7 1.25 52.5 1.73 72.3 SWAMPSCOTT 1931 0.006 0.11 0.25 4.8 0.63 12.1 0.86 16.7 SWANSEA 12599 0.007 0.86 0.31 38.6 0.78 97.7 1.07 134.5 TISBURY 3539 0.012 0.41 0.52 18.5 1.32 46.8 1.82 64.5 TRURO 10734 0.006 0.61 0.26 27.5 0.65 69.7 0.89 96.1 WAREHAM 19822 0.024 4.70 1.07 211.4 2.70 535.6 3.72 737.6 WELLFLEET 9127 0.011 1.01 0.50 45.6 1.27 115.5 1.74 159.1 WESTPORT 27340 0.004 1.12 0.18 50.4 0.47 127.8 0.64 176.0 WEST TISBURY 14466 0.006 0.90 0.28 40.4 0.71 102.2 0.97 140.8 WEYMOUTH 9944 0.001 0.14 0.06 6.3 0.16 15.9 0.22 21.9 WINTHROP 300 0.021 0.06 0.94 2.8 2.37 7.1 3.27 9.8 YARMOUTH 12556 0.026 3.21 1.15 144.6 2.92 366.4 4.02 504.7 TOTALS 804246 65.4 2945. 7459. 10273. The following coastal towns loose less than 0.001% of their total upland area annually as the result the historical mean sea-level rise rate of 0.01 ft/yr, and therefore were omitted from this table: Braintree, Hanover, Milton, Norwell, Peabody and Pembroke. 9 acres; Barnstable, 3.7 acres; and Yarmouth, 3.2 acres. In terms of annual percentage of total upland lost per year, the communities most affected are: Marion, which loses 0.03 1 % per year, followedI by Nantucket which looses 0.027 % per year, and Hull and Yarmouth, which loose 0.026% per year.3 Looking forward to the year 2025, if the historical rate of relative sea-level rise were to remain unchanged (case 1), the total Massachusetts upland loss would be 2,945 acres. A relative3 sea-level rise of 1. 14 ft, as projected in case 2, would be accompanied by an upland loss of 7,459 acres, and a rise of 1.57 ft (case 3) would cost the commonwealth 10,273 acres of upland. When considering these figures, it is important to realize that they do not include the upland losses that would result from the response of ground water levels to sea-level rise. In those communities where bedrock is absent and the terrain consists of unconsolidated sediments, theI water table level over geological time periods is controlled by relative sea level. As sea level rises, the water table level rises with it, increasing the size of existing streams, ponds and bogs, and creating new ones. This effect has not been included in the hypsometric analysis discussed above, although it was taken into account in the construction of the color-coded maps.3 The reader also should bear in mind that the calculated upland retreat rates are based on the assumption that the coastal uplands have a natural form and are not protected by engineering structures. Particularly in urban coastal areas where seawalls, riprap and fill are prevalent, the actual losses will be less than those predicted here. As the color-coded maps indicate, however, when large values of sea-level rise are considered, these structures are overwhelmed. It is of interest that the presently existing rate of upland retreat due to the passive effects of relative sea-level rise is much greater than the upland retreat rate due to active wave-produced3 erosion. This may be illustrated by a consideration of the Cape Cod coast, which is well-known as a region of rapid erosion. While detailed estimates for cliff retreat do not exist for the entire region,3 the rate of erosion of the outer coast is well-known (e.g., Zeigler et al., 1964), and reasonable estimates can be made for the remaining and more slowly retreating cliff areas. Using such existing3 information and reasonable estimates, the annual upland loss experienced by Cape Cod as the result of active wave-produced erosion is about 9 acres per year. On the other hand, the annual loss due to the passive effects of relative sea-level rise, calculated from the figures for each CapeI Cod town listed in Table 1, is about 24 acres per year. Thus it is seen that even considering a region of rapid erosion, and excluding the effects ground water table rise, passive retreat accounts3 for 73% of coastal upland loss under present conditions. Figures 2, 3, and 4 present the color-coded maps depicting the submergence patterns of3 Hyannis, Gloucester, and Westport harbors that would accompany each of the four Hoffman (1984) sea-level rise scenarios for the year 2100. The maps show in red the land areas that would be lost given the low scenario rise of 1.8 ft, in yellow the submerged areas given the mid-range low scenario rise of 4.7 ft, and in green and blue the areas submerged by the mid-range high scenario rise of 7.1 ft and the high range scenario rise of 11.3 ft respectively. The low scenario changes are 10I extensive only in wetland areas, such as the salt marshes northwest of Gloucester Harbor, the sand I ~~spit southwest of Hyannis Harbor, and fringing marshes in Westport Harbor. While the upland lost given this scenario is not extensive, the increased potential for storm wave and flooding damage I~~~should beof concern. The submergence that would accompany the other scenarios is extensive and would impact 3 ~~severely operations of harbor facilities. In addition, the maps show locally significant flooding of inland areas for these scenarios resulting from elevated ground water levels. As has been discussed above, it should be kept in mind that the levels used in applying these scenarios do not include the effects of coastal subsidence, and that for the lower rise rates the increases would be significant I ~~were they to be included. CONCLUSIONS 3 ~~~Major conclusions of the present study are: I1. Relative sea-level rise is the major process responsible for upland loss in Massachusetts. I ~ ~~Neglecting coastal erosion and fresh water table changes, Massachusetts presently looses about 65 acres of upland each year due to passive submergence. I ~ ~2. The rate of upland loss due to passive submergence varies widely from town to town, and depends upon the geology of the region in which the town lies. 1 ~~3. The hypsometric curves of the towns provide important basic information that permits the calculation of the upland areas which those towns will lose to passive submergence as the result of any given increase in relative sea-level. 4. The total land loss by the year 2025 has been calculated for several relative sea-level rise scenarios. At the present rate of rise, Massachusetts will have lost about 3,000 acres of upland between 1980 and 2025. This is the same upland loss that occurred between 1935 and 1980, an equal length of time. For a rise of 1. 14 ft, about 7,500 acres would be lost; and for a rise of 1.57 ft, the maximum Riely, over 10,000 acres would be lost. Given a nominal value of ocean-front property of $1,000,000 per acre, the economic impact of this retreat is substantial. 3 ~~5. Color-coded maps are a useful device for depicting the specific areas that will be submerged as the result of specified increases in relative sea level. These maps could be developed for each 3 ~~~coastal town in the future, to provide guidance for land use, public works, and conservation decisions. 6. These data can be used immediately to help provide a rational basis for local response to global climate warmning. Data from this report, although representing hypothetical scenarios, remove the quantification of the impacts of passive retreat from the realm of speculation, placing them on a firmer basis. Although enactment of legislation and major revision of regulations may be premature, local communities must increase their awareness of these impacts, and begin to 3 ~~~~incorporate these data in planning, design, and conservation issues. 7. Although the present study has shown that passive retreat is an important element of the shoreline response to anticipated global climate change, this inundation is certainly not the sole impact. Future research is mandated for other impacts on the coast of Massachusetts, including but not limited to: Effects of relative sea-level rise on groundwater resources. Effects of relative sea-level rise on marshes and other biotopes. Possible global climate change impact on storm climatology of Massachusetts waters. ACKNOWLEDGEMENTS This study has benefited from the contributions of many of our colleagues at the Woods Hole Oceanographic Institution. We are grateful for the assistance of Chris Pelloni of the Woods Hole office of the U.S. Geological Survey who provided coordinate translation of the numerical data. Jeff Benoit, of the Massachusetts Office of Coastal Zone Management, provided the foresight and management ability which made the study a reality. REFERENCES Aubrey, D.G. and K.O. Emery, 1983. Eigenanalysis of recent United States sea levels. Continental Shelf Research, v. 2, n. 1, p. 21-33. Bird, E.C.F., 1976. Shoreline changes during the past century. In Proc. 23rd International Geographical Congress, Moscow, 54 p. Braatz, B.V. and D.G. Aubrey, 1987. Recent relative sea-level change in eastern North America. Journal of Sedimentary Petrology, in press. Giese, G.S., H. Bokuniewicz, G. Zarillo, M.Zimmerman, J. Hennessy, G. Smith and S. Tangren, 1984. Hypsometry as a tool for calculating coastal submergence rates. Proc. 4th Sym. on Coastal and Ocean Management, v. 2, p. 1971-1978. Hoffman, J., D. Keyes and J. Titus, 1983. Projecting future sea-level rise: methodology, estimates to the year 2100 and research needs. U.S. Environmental Protection Agency, EPA 230-09-007, Washington, DC, 121 p. Mandelbrot, B.B., 1977. Fractals: Form. Chance. and Dimension. W.H. Freeman and Co., San Francisco, 365 p. Zeigler, J.M., S.D. Tuttle, G.S. Giese and H.J. Tasha, 1964. Residence time of sand composing the beaches and bars of Outer Cape Cod. Proc. 9th Cont.on Coastal Engineering, p. 403-416. 12 14000 MASSACHUSETTS COASTAL SUBMERGENCE PROJECT 13900 13600 R~ 13700 13500lo 13400 oiEli - 13300 13200 13100 13000) 12900 12900 12?2I: 126000 12500 12400 12300 12200 12100) 12000 11900 11100~~~~~~~~~~~~ 112000 10900~~~~~~~~~~~~~~~~~~~~~~~~~ 10900 107000 10700 105000- 10500 10400 20200 10100 10000 9000-- 9800 9700 96000 95000 94(0 9300 9200 9100 91000 91200 91400 910,00 91000 9--2000 92200 92402 92000 9290 030 93200 -9 402 01020 :1038c 942100 91 201 944001 94600 94800 95000 East"ing (in.) pn~tc 0 t~ dcmn rna440 ff~~O 9s~0 t. oI*0 HYANNIS HARBOR M ~ Cat aaenn 02.00 onO 000.140 Osatano. hI~~~~~~~~~~~~r..~~.Man.KlosI 4*SC 100asoach0usetts Casa zone ma~nad Officee .1~~~~~~Mt u..~omrd bm. 9MI Wooit. 24 Figure 2 13 MASSACHUSETTS COASTAL SUBMERGENCE PROJECT 20400 20200 20200 :0.:", ~ ~ ~ ~ ~ ~~~~~~~I win E 1~~~~~~~~~~0~~P m 19wo~~~~~~~~~~~I! 192,00 16700 16000 16500 i t - 0 000 Ann! .131 ~~~~6100~ ~ ~ ~ ~~~1 10OMASSACHUSETTS COASTAL SUBMERGENC PROJECT 09900 99500 99400 00.700 00400 90000 00000 00400 00100 9810 98.0000 07700 077000 97500 07100 00700 08000 00500 00400 00300 00200 060000-0 25407 2002 25000 27000 26200 24000 24200 2440 24600 240110 250204 25202 204110 20600U 20000 272 24200 07400 27000 0700 Oo Easting (in) 85~~ ~~s. .1 2~~~ ~~ ~~ 4~~. 0.54WSTPOR0HARORI Massachusetts Coastal Zone Managemnent office 05.0 .50 COSSOSI 955504.0909.8.54 950555 ~~~~~~ .11.31 .. Ridosrdf. D.1880,DJ, DO..i ...- Figure 4 17 I I I a I APPENDIX A Hypsometry by Town: I Tables & Graphs I I I I I I a a I I A-1 ACUSHNET ELEVATION CUMULATIVE PERCENT 3 0.61 4 1.21 5 1.82 6 2.30 7 2.85 8 3.54 9 5;00 10 6.36 11 7.94 12 10.75 13 13.79 14 22.09 15 26.77 16 31.45 17 36.14 18 39.66 19 43.01 20 47.07 21 50.28 22 53.85 23 57.73 24 65.46 25 69.34 26 72.49 27 76.01 28 78.46 29 80.79 30 82.78 31 84.77 32 86.76 33 88.28 34 90.25 35 91.71 36 93.13 37 94.52 38 95.47 39 96.18 40 96.85 41 97.56 42 98.12 43 98.57 44 98.82 45 98.94 46 99.06 47 99.18 48 9930 49 99.41 50 99.50 51 99.60 52 99.68 53 99.74 54 99.81 55 99.87 56 99.91 57 99.95 58 99.97 59 99.99 60 100.00 A-2 ACUSHNET HYPSOMETRY CALCULATED FOR UPLAND 3m.+ o 0- 0-, O U O X- 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-3 BARNSTABLE ELEVATION CUMULATIVE PERCENT 3 3.96 4 7.92 5 11.89 6 14.74 7 17.43 8 20.09 9 23.44 10 25.92 11 29.79 12 32.94 13 35.47 14 38.91 15 43.59 16 48.27 17 52.94 18 57.14 19 60.79 20 64.56 21 67.61 22 70.33 23 73.28 24 75A7 25 77.47 26 79.22 27 81.13 28 82.57 29 83.85 30 85.16 31 86.48 32 87.79 33 88.89 34 90.05 35 90.99 36 91.90 37 92.81 38 93.53 39 94.20 40 94.78 41 95.48 42 95.99 43 96.33 44 96.68 45 96.92 46 97.15 47 97.39 48 97.63 49 97.83 50 98.02 51 98.20 52 98.48 53 98.64 54 98.79 55 98.94 56 99.08 57 99.21 58 99.35 59 99.48 60 99.61 A-6 BARNSTABLE HYPSOMETRY CALCULATED FOR UPLAND 3m.+ O - 0- C: oI O - 010 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-7 BERKLEY ELEVATION CUMULATIVE PERCENT 3 1.47 4 2.95 5 4.42 6 5.65 7 6.90 8 8.21 9 10.13 10 11.68 11 13.45 12 15.88 13 18.16 14 20.83 15 24.38 16 27.94 17 31.49 18 34.85 19 38.26 20 42.09 21 45.17 22 48.32 23 51.94 24 54.61 25 57.33 26 60.10 27 63.79 28 66.77 29 70.38 30 73.67 31 76.96 32 80.26 33 83.29 34 86.07 35 88.61 36 90.89 37 92.92 38 94.69 39 96.21 40 97.48 41 98.49 42 99.25 43 99.75 44 100.00 A-8 BERKLEY HYPSOMETRY CALCULATED FOR UPLAND 3m.-+ 0o M-4 CO U - - 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-9 BEVERLY ELEVATION CUMULATIVE PERCENT 3 0.95 4 1.90 5 2.85 6 3.64 7 4.91 8 5.98 9 6.93 10 8.46 11 9.94 12 11.47 13 13.32 14 19.10 15 24.88 16 30.67 17 35.69 18 40.09 19 44.02 20 47.54 21 51.49 22 54.81 23 57.88 24 61.28 25 63.76 26 66.63 27 69.14 28 72.44 29 77.00 30 79.51 31 82.03 32 84.54 33 86.79 34 88.85 35 90.84 36 92.53 37 94.07 38 9536 39 96.55 40 97.54 41 98.37 42 98.90 43 99.32 44 99.60 45 99.65 46 99.69 47 99.74 48 99.77 49 99.81 50 99.84 51 99.87 52 99.90 53 99.92 54 99.94 55 99.95 56 99.97 57 99.98 58 100.00 A-10 BEVERLY HYPSOMETRY CALCULATED FOR UPLAND 3m.+ O co o : 10A 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-li BOSTON ELEVATION CUMULATIVE PERCENT 3 2.92 4 5.85 5 8.77 6 1133 7 14.42 8 16.71 9 18.85 10 21.43 11 23.54 12 25.99 13 28.21 14 30.97 15 34.13 16 37.30 17 40A7 18 42.93 19 45.45 20 47.84 21 50.31 22 52.46 23 54.53 24 56.93 25 58.86 26 60.91 27 62.75 28 65.16 29 67.23 30 68.99 31 70.75 32 72.51 33 73.94 34 75.33 35 76.60 36 77.70 37 78.85 38 79.87 39 80.85 40 81.90 41 82.79 42 83.89 43 84.83 44 85.93 45 87.10 46 88.28 47 89A5 48 90.43 49 91.22 50 91.98 51 92.64 52 93.32 53 94.01 54 94.53 55 95.00 56 95.57 57 95.96 58 9637 59 96.62 60 97.95 A-12 BOSTON HYPSOMETRY CALCULATED FOR UPLAND 3m.+ O - oC co: *O D o * Cr 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-13 BOURNE ELEVATION CUMULATIVE PERCENT 3 2.09 4 4.18 5 6.27 6 7.94 7 9.41 8 10.85 9 12.75 10 14.09 11 15.70 12 17.41 13 18.73 14 20.12 15 21.95 16 23.79 17 25.62 18 27.34 19 29.04 20 30.87 21 3230 22 33.66 23 35.32 24 36.64 25 37.90 26 39.10 27 40.64 28 42.00 29 4326 30 45.24 31 47.21 32 49.18 33 51.15 34 52.95 35 54.54 36 56.08 37 57.62 38 59.03 39 6031 40 61.66 41 63.02 42 64.20 43 65.25 44 66.36 45 67.86 46 69.35 47 70.84 48 72.51 49 73.86 50 75.07 51 76.15 52 77.43 53 78.49 54 7936 55 80.45 56 81.29 57 82.13 58 82.98 59 84.13 60 85.22 A-14 BOURNE HYPSOMETRY CALCULATED FOR UPLAND 3mnt� o o/ 0- 30 o 20 30 40 50 60 70 80 90 oo Percent of Upland Area A-15 I~_ ' BREWSTER ELEVATION CUMULATIVE PERCENT 3 1.68 4 336 5 5.03 6 6.11 7 7.24 8 10.72 9 14.05 10 15.91 11 17.80 12 20.52 13 22.63 14 25.24 15 29.72 16 34.19 17 38.66 18 42.84 19 46.98 20 51.28 21 54.78 22 57.83 23 61.32 24 64.18 25 66.85 26 69.19 27 71.85 28 73.97 29 76.13 30 78.92 31 81.71 32 84.51 33 88.79 34 93.32 35 94.88 36 96.23 37 97.49 38 98.14 39 98.67 40 99.13 41 99.48 42 99.74 43 99.92 A-16 BREWSTER HYPSOMETRY CALCULATED FOR UPLAND 3m.+ O_- 0- 0 to 20 30 40 50 60 70 80 90 100 * ~~Percent of Upland Area 3CO ~~~~~A-17 ~~01 0304 06 7 09 0 F:~ ~ ecn o padAe ''i C3~~~~~~A1 CHATHAM ELEVATION CUMULATIVE PERCENT 3 6.48 4 12.95 5 19.43 6 24.58 7 28.69 8 33.32 9 38.44 10 42.10 11 46.40 12 51.06 13 55.05 14 59.56 15 64.50 16 69.43 17 74.36 18 78.72 19 82.57 20 86.02 21 89.01 22 91.31 23 93.43 24 95.19 25 96.70 26 97.85 27 98.70 28 99.27 29 99.58 30 99.64 31 99.70 32 99.76 33 99.79 34 99.82 35 99.85 36 99.88 37 99.91 38 99.94 39 99.97 A-18 CHATHAM HYPSOMETRY CALCULATED FOR UPLAND 3m.+ CD - - o-- 3 -1 O O- r-' C o 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-19 CHELSEA ELEVATION CUMULATIVE PERCENT 3 3.23 4 6.45 5 9.68 6 12.52 7 16.39 8 19.74 9 22.19 10 25.55 11 29.16 12 34.71 13 43.87 14 49.03 15 54.19 16 59.35 17 65.42 18 69.68 19 73.81 20 77.55 21 81.42 22 84.77 23 87.74 24 90.06 25 91.61 26 93.16 27 94.71 28 95.48 29 96.00 30 96.65 31 97.29 32 97.94 33 98.32 34 98.84 35 99.10 36 99.48 37 99.61 38 99.87 39 100.00 A-20 CHELSEA HYPSOMETRY CALCULATED FOR UPLAND 3m.+ 0- O_ - 0- A-21 CHILMARK ELEVATION CUMULATIVE PERCENT 3 3.21 4 6.41 5 9.62 6 11.89 7 14.05 8 15.90 9 19.15 10 20.31 11 21.62 12 22.61 13 23.83 14 24.59 15 25.84 16 27.10 17 28.36 18 29.84 19 31.26 20 32.73 21 33.86 22 35.02 23 36.67 24 37.88 25 38.96 26 40.11 27 41.56 28 42.58 29 43.47 30 45.33 31 47.18 32 49.03 33 50.84 34 52.74 35 54.14 36 55.62 37 57.08 38 58.46 39 59.72 40 60.91 41 62.34 42 63.44 43 64.56 44 65.55 45 67.42 46 69.29 47 71.15 48 73.50 49 74.94 50 76.47 51 77.89 52 79.76 53 80.86 54 82.18 55 83.91 56 84.85 57 86.00 58 86.87 59 88.12 60 89.25 A-22 CHILMARK HYPSOMETRY CALCULATED FOR UPLAND 3m.+ O 0 3) C: 3, o 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-23 COHASSET ELEVATION CUMULATIVE PERCENT 3 1.00 4 2.00 5 3.00 6 3.74 7 5.22 8 6.28 9 7.56 10 9.30 11 11.01 12 13.50 13 16.43 14 23.31 15 30.19 16 37.06 17 43.59 18 49.02 19 53.95 20 58.57 21 63.42 22 67.82 23 71.50 24 75.24 25 78.72 26 81.43 27 84.17 28 86.85 29 89.81 30 90.93 31 92.04 32 93.15 33 94.07 34 94.92 35 95.75 36 96.71 37 97.12 38 97.72 39 98.23 40 98.57 41 98.86 42 99.14 43 9934 44 99.43 45 99.49 46 99.54 47 99.60 48 99.66 49 99.71 50 99.77 51 99.83 52 99.86 53 99.89 54 99.91 55 99.94 56 99.97 57 100.00 A-24 COHASSET HYPSOMETRY CALCULATED FOR UPLAND 3m.+ o O- 0- Percent of Upland Area OA-25 O - 3 O Percent of Upland Area A-25 DANVERS ELEVATION CUMULATIVE PERCENT 3 1.04 4 2.08 5 3.11 6 4.27 7 5.81 8 7.19 9 8.62 10 10.72 11 12.79 12 15.21 13 18.26 14 21.74 15 25.21 16 28.68 17 31.94 18 34.83 19 37.43 20 40.16 21 43.03 22 45.35 23 47.78 24 5034 25 52.83 26 55.45 27 58.26 28 62.20 29 66.93 30 69.62 31 7232 32 75.01 33 77.15 34 7930 35 81.74 36 83.19 37 84.99 38 86.55 39 88.20 40 89.64 41 90.76 42 92.00 43 92.81 44 93.67 45 94.27 46 94.87 47 95.47 48 95.85 49 96.29 50 96.67 51 97.01 52 97.37 53 97.82 54 98.06 55 9832 56 9854 57 98.76 58 98.94 59 99.00 60 99.44 A-26 DANVERS HYPSOMETRY CALCULATED FOR UPLAND 3m.+ 0- > CO- Q- I o 4) - -/ 0 [0 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-27 DARTMOUTH ELEVATION CUMULATIVE PERCENT 3 1.92 4 3.85 5 5.77 6 7.38 7 8.91 8 10.51 9 12.54 10 14.24 11 15.93 12 18.58 13 20.75 14 23.21 15 25.53 16 27.84 17 30.16 18 32.61 19 34.66 20 37.01 21 38.91 22 40.70 23 42.81 24 44.48 25 46.27 26 48.03 27 50.34 28 52.47 29 54.70 30 58.05 31 61.39 32 64.74 33 67.83 34 71.06 35 73.68 36 76.17 37 78.80 38 80.88 39 82.86 40 84.54 41 86.44 42 87.79 43 88.96 44 89.92 45 90.86 46 91.79 47 92.73 48 93.67 49 94.40 50 95.04 51 95.62 52 96.18 53 96.61 54 96.96 55 9738 56 97.67 57 97.88 58 98.05 59 98.25 60 98.41 A-28 DARTMOUTH HYPSOMETRY CALCULATED FOR UPLAND 3m.+ O - A-29 3 DENNIS ELEVATION CUMULATIVE PERCENT 3 7.75 4 15.50 5 23.25 6 28.62 7 33.18 8 37.64 9 4259 10 46.34 11 49.60 12 53.21 13 55.68 14 58.25 15 61.87 16 65.49 17 69.11 18 72.64 19 75.72 20 78.77 21 81.42 22 83.84 23 8622 24 88.09 25 89.77 26 91.01 27 9234 28 93.25 29 94.02 30 9458 31 95.15 32 95.72 33 96.13 34 96.71 35 97.10 36 97.41 37 97.85 38 98.09 39 98.37 40 98.65 41 98.86 42 99.10 43 99.21 44 99.43 45 99.49 46 99.55 47 99.61 48 99.67 49 99.72 50 99.76 51 99.81 52 99.85 53 99.88 54 99.91 55 99.94 56 99.96 57 99.97 58 99.99 59 100.00 A-30 DENNIS HYPSOMETRY CALCULATED FOR UPLAND 3m.+ O- *~ c.O Oo U~~~~~~ * -C - rT] / lii I I I II 11 I I I II II II 11)111111 III II 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-31 DIGHTON ELEVATION CUMULATIVE PERCENT 3 1.91 4 3.83 5 5.74 6 7.18 7 8.43 8 9.65 9 11.29 10 1253 11 13.81 12 15.57 13 16.85 14 18.13 15 19.90 16 21.67 17 23.44 18 25.14 19 26.51 20 28.29 21 29.66 22 30.94 23 32.57 24 33.80 25 35.06 26 36.51 27 38.62 28 40.19 29 42A5 30 48.56 31 54.67 32 60.78 33 65.74 34 70.32 35 73.78 36 76.49 37 78.84 38 80.72 39 82.49 40 84.12 41 85.67 42 86.93 43 87.89 44 88.76 45 89.47 46 90.18 47 90.90 48 92.10 49 93.15 50 94.00 51 94.65 52 95.54 53 96.10 54 96.70 55 9733 56 97.62 57 97.90 58 98.18 59 9853 60 98.76 A- 32 DIGHTON HYPSOMETRY CALCULATED FOR UPLAND 3m.+ 0 O O- O - o- 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area 3 o~~~ O~A-33 DUXBURY ELEVATION CUMULATIVE PERCENT 3 0.64 4 1.28 5 1.92 6 2.54 7 3.41 8 4.12 9 4.90 10 6.17 11 7.40 12 8.74 13 10.33 14 1551 15 21.89 16 28.27 17 34.65 18 39.80 19 44.75 20 49.28 21 5357 22 57.14 23 60.79 24 64.47 25 67.77 26 70.55 27 73.18 28 75.90 29 78.67 30 81.83 31 84.98 32 88.14 33 90.43 34 92.20 35 93.93 36 95.21 37 96.18 38 96.98 39 97.77 40 98.41 41 98.89 42 99.26 43 99.54 44 99.67 45 99.70 46 99.74 47 99.78 48 99.81 49 99.84 50 99.86 51 99.89 52 99.91 53 99.94 54 99.95 55 99.96 56 99.98 57 99.99 58 100.00 A-34 DUXBURY HYPSOMETRY CALCULATED FOR UPLAND 3m.+ 0 o O 0 10 20 30 40 50 60 70 80 90 100 M *E 'Aj 35 - / 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-35 EASTHAM ELEVATION CUMULATIVE PERCENT 3 4.53 4 9.06 5 13.59 6 17.29 7 20.95 8 24.69 9 28.79 10 32.32 11 35.89 12 50.61 13 55.43 14 60.01 15 64.83 16 69.65 17 74.47 18 8454 19 88.30 20 91.61 21 95.16 22 96.24 23 97.17 24 97.99 25 98.66 26 99.18 27 99.59 28 99.86 A-36 EASTHAM HYPOSOMETRY CALCULATED FOR UPLAND 3m.+ *D Co - O- I 00 C.- 0 O10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-37 EDGARTOWN ELEVATION CUMULATIVE PERCENT 3 8.03 4 16.06 5 24.09 6 29.67 7 34.82 8 39.80 9 57.85 10 62.43 11 66.00 12 70.35 13 73.66 14 77.12 15 80.17 16 83.22 17 86.27 18 88.99 19 91.17 20 93.49 21 95.08 22 96.46 23 97.63 24 98.50 25 98.98 26 9935 27 99.65 28 99.87 29 100.00 A-38 EDGARTOWN HYPSOMETRY CALCULATED FOR UPLAND 3m.+ *- Ui - 3 I CO- O 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-39 ESSEX ELEVATION CUMULATIVE PERCENT 3 1.16 4 2.32 5 3.48 6 4.82 7 6.53 8 8.25 9 9.88 10 12.28 11 14.30 12 17.12 13 20.05 14 26.07 15 32.10 16 38.12 17 43.32 18 48.11 19 52.22 20 56.05 21 60.04 22 63.36 23 66.29 24 69.26 25 71.86 26 74.41 27 76.50 28 78.82 29 81.22 30 83.31 31 85.40 32 87.49 33 89.18 34 90.72 35 92.28 36 93.60 37 94.76 38 95.74 39 96.67 40 97.43 41 98.01 42 98.41 43 98.89 44 99.07 45 99.17 46 99.27 47 9937 48 99.47 49 99.55 50 99.62 51 99.70 52 99.75 53 99.80 54 99.85 55 99.90 56 99.92 57 99.95 58 99.97 59 100.00 A-40 ESSEX HYPSOMETRY CALCULATED FOR UPLAND 3m.+ CQ - O - '*7-- 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-41 EVERETT ELEVATION CUMULATIVE PERCENT 3 2.69 4 537 5 8.06 6 1139 7 14.91 8 18.70 9 22.96 10 27.13 11 31.48 12 36.02 13 41.39 14 44.44 15 47.50 16 50.56 17 55.19 18 58.06 19 61.39 20 63.70 21 67.87 22 71.20 23 73.70 24 77.22 25 80.09 26 82.59 27 84.17 28 86.02 29 87.13 30 88.89 31 90.65 32 92.41 33 95.74 34 96.20 35 96.94 36 97.22 37 97.78 38 98.15 39 98.33 40 98.52 41 98.70 42 98.98 43 99.07 44 99.07 45 99.17 46 99.26 47 99.35 48 99.44 49 99.54 50 99.63 51 99.72 52 99.81 53 99.91 54 100.00 A-42 EVERETT HYPSOMETRY CALCULATED FOR UPLAND 3m.- O.. O - UA- CO -,,IIII IIIIIIII III IIIIIIIIIIII IIIIIIIIltl tl tII!IIlIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII 1 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-43 FAIRHAVEN ELEVATION CUMULATIVE PERCENT 3 656 4 13.13 5 19.69 6 23.67 7 2758 8 3138 9 3538 10 38.71 11 41.76 12 45.81 13 4946 14 5340 15 58.78 16 64.15 17 6953 18 74.49 19 7935 20 84.64 21 88.34 22 91.22 23 9430 24 9651 25 97.84 26 98.77 27 99.67 28 99.88 29 100.00 A-44 FAIRHAVEN HYPSOMETRY CALCULATED FOR UPLAND 3m.+ 0 - > Q0 o O - 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-45 FALL RIVER ELEVATION CUMULATIVE PERCENT 3 0.27 4 055 5 0.82 6 1.01 7 1.32 8 152 9 1.78 10 1.99 11 2.22 12 251 13 2.71 14 2.94 15 3.15 16 3.37 17 3.58 18 3.83 19 4.06 20 4.39 21 4.56 22 4.74 23 5.12 24 5.32 25 5.53 26 5.71 27 6.09 28 6.22 29 6.40 30 6.76 31 7.13 32 7.49 33 7.80 34 8.26 35 8.67 36 9.05 37 9.63 38 10.03 39 10.63 40 14.89 41 17.42 42 19.83 43 23.11 44 26.68 45 28.85 46 31.02 47 33.18 48 35.91 49 38.17 50 40.30 51 42.55 52 45.16 53 47.48 54 49.74 55 53.12 56 5557 57 58.26 58 61.18 59 65.16 60 68.24 A-46 FALL RIVER HYPSOMETRY CALCULATED FOR UPLAND 3m.+ o I -I cO O - I 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-47 FALMOUTH ELEVATION CUMULATIVE PERCENT 3 5.16 4 10.31 5 15.47 6 19.79 7 23.29 8 26.60 9 30.16 10 33.09 11 36.66 12 40.20 13 43.06 14 46.13 15 49.73 16 53.32 17 56.92 18 59.99 19 62.85 20 65.72 21 67.93 22 69.98 23 72.14 24 73.77 25 7535 26 76.77 27 7838 28 79.170 29 80.98 30 82.75 31 84.53 32 86.30 33 87.86 34 89.39 35 90.53 36 91.60 37 92.63 38 93.39 39 94.09 40 94.74 41 95.45 42 95.97 43 96.42 44 96.84 45 97.18 46 97.52 47 97.86 48 98.17 49 98.43 50 98.68 51 98.88 52 99.09 53 99.24 54 99.39 55 99.54 56 99.63 57 99.73 58 99.82 59 99.90 60 99.93 A-48 FALMOUTH HYPSOMETRY CALCULATED FOR UPLAND 3m.+ O- * O49 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-49 FREETOWN ELEVATION CUMULATIVE PERCENT 3 0.55 4 1.09 5 1.64 6 198 7 2.44 8 2.86 9 4.04 10 4.76 11 5.61 12 6.88 13 7.83 14 9.19 15 11.50 16 13.81 17 16.12 18 17.75 19 19.41 20 21.48 21 22.97 22 24.52 23 26.57 24 30.15 25 31.48 26 32.99 27 34.81 28 36.19 29 37.47 30 40.54 31 43.62 32 46.69 33 49.81 34 53.09 35 55.41 36 57.76 37 60.14 38 61.85 39 63.54 40 65.11 41 66.83 42 68.21 43 69.56 44 70.76 45 72.68 46 74.60 47 76.52 48 78.40 49 79.84 50 81.08 51 82.28 52 83.53 53 84.56 54 85.60 55 86.68 56 87.48 57 88.26 58 88.97 59 89.86 60 90.52 A-50 FREETOWN HYPSOMETRY CALCULATED FOR UPLAND 3m.+ ~I~Pre ofUlnAr IA- oZ 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area U ~~~~~~~~~~A-51 GAYHEAD ELEVATION CUMULATIVE PERCENT 3 4.04 4 8.07 5 12.11 6 15.47 7 18.22 8 21.02 9 2534 10 27.69 11 30.16 12 33.35 13 35.93 14 38.51 15 40.98 16 43.44 17 45.91 18 47.98 19 50.56 20 52.80 21 54.60 22 57.12 23 59.98 24 62.00 25 63.68 26 65.70 27 68.50 28 70.07 29 72.09 30 73.99 31 75.90 32 77.80 33 79.48 34 81.56 35 83.13 36 8436 37 86.49 38 8733 39 88.68 40 89.91 41 91.03 42 92.15 43 93.39 44 94.56 45 95.18 46 95.80 47 96.41 48 97.14 49 97.65 50 97.98 51 98.32 52 98.60 53 98.88 54 99.22 55 99.50 56 99.66 57 99.78 58 99.94 59 100.00 A-52 GAY HEAD HYPSOMETRY CALCULATED FOR UPLAND 3m.+ O So- O : 0 10 20 30 40 50 60 70 80 90 100 / Percent of Upland Area A-53 GLOUCESTER ELEVATION CUMULATIVE PERCENT 3 1.04 4 2.07 5 3.11 6 4.14 7 5.52 8 6.60 9 7.78 10 9.44 11 10.81 12 12.65 13 14.45 14 19.51 16 29.63 17 34.22 18 38.08 19 41.81 20 45.06 21 48.58 22 51.57 23 53.96 24 56.41 25 58.65 26 60.72 27 62.49 28 64.64 29 66.98 30 68.69 31 70.41 32 72.12 33 73.67 34 75.10 35 76.61 36 77.96 37 79.12 38 80.18 39 81.36 40 82.29 41 83.15 42 84.27 43 85.36 44 86.66 45 88.08 46 89.49 47 90.90 48 92.23 49 93.40 50 94.47 51 9538 52 96.27 53 97.02 54 97.66 55 98.23 56 98.67 57 99.07 58 9939 59 99.62 60 99.99 A-54 GLOUCESTER HYPSOMETRY CALCULATED FOR UPLAND 3m.+ O U - o 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-55 GOSNOLD ELEVATION CUMULATIVE PERCENT 3 439 4 8.77 5 13.16 6 16.07 7 19.02 8 22.06 9 2637 10 29.33 11 31.74 12 35.43 13 37.94 14 40.77 15 45.06 16 49.34 17 53.62 18 57.49 19 60.89 20 6437 21 67.40 22 70.13 23 72.85 24 75.53 25 77.76 26 79.65 27 82.56 28 84.35 29 85.75 30 87.49 31 89.23 32 90.97 33 92.45 34 93.80 35 94.81 36 95.72 37 96.55 38 97.07 39 97.66 40 98.13 41 98.57 42 98.96 43 99.14 44 99.27 45 99.38 46 99.48 47 99.58 48 99.69 49 99.74 50 99.79 51 99.84 52 99.87 53 99.90 54 99.92 55 99.95 56 99.97 57 100.00 A-56 GOSNOLD H'YPSOMETRY CALCULATED FOR UTPLAND 3m.t .z 0 io 20 30 40 5o 60 70 80 90 100 3 ~~Percent of Upland Area 3 ~~~~~~~~A-57 A-57 HARWICH ELEVATION CUMULATIVE PERCENT 3 5.31 4 10.62 5 15.92 6 19.98 7 23.76 8 27A1 9 33.02 10 36.21 11 39.24 12 42.72 13 45.66 14 48.66 15 55.15 16 61.64 17 68.13 18 73.85 19 78.70 20 83.54 21 87.01 22 90.02 23 92.70 24 94.93 25 96.71 26 98.09 27 99.10 28 99.72 A-58 HARWICH HYPSOMETRY CALCULATED FOR UPLAND 3m.+ C - o coo o- 3 0 - t-~ ~~~~~~~' ~~~~~~~~~ { ~'~~~,, IIII {~~ ~~I~ ~~I~ I,,,,, III II II { '| I{ ~ "I I ! {'{ . . . . " " I, 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-59 HINGHAM ELEVATION CUMULATIVE PERCENT 3 0.62 4 1.24 5 1.87 6 2.62 7 3.75 8 4.69 9 5.67 10 6.82 11 7.98 12 9.22 13 10.66 14 1535 15 20.04 16 24.73 17 29.10 18 32.68 19 36.25 20 39.47 21 42.59 22 45.50 23 48.17 24 50.78 25 53.01 26 55.21 27 5731 28 59.99 29 62.90 30 65.09 31 67.28 32 69.47 33 71.37 34 73.04 35 75.02 36 76.50 37 78.10 38 79.59 39 81.17 40 82.72 41 84.15 42 85.93 43 87.47 44 89.10 45 90.20 46 91.31 47 92.42 48 93.49 49 94.44 50 95.31 51 96.10 52 96.83 53 97.49 54 98.06 55 98.58 56 98.96 57 99.33 58 99.56 59 99.76 60 100.00 A-60 HINGHAM HYPSOMETRY CALCULATED FOR UPLAND 3m.+ C) - C,- O - A61 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-61 HULL ELEVATION CUMULATIVE PERCENT 3 8.62 4 17.25 5 25.87 6 31.83 7 39.01 8 43.94 9 48.25 10 53.59 11 59.34 12 63.24 13 69.20 14 72.28 15 75.36 16 78.44 17 81.11 18 8337 19 86.24 20 88.50 21 90.14 22 91.99 23 93.02 24 94.05 25 95.07 26 96.30 27 96.71 28 97.33 29 98.15 30 9836 31 98.56 32 98.77 33 9897 34 9938 35 99.59 36 99.79 37 100.00 A-62 HULL HYPSOMETRY CALCULATED FOR UPLAND 3m.+ 0o 0- - C -' 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-63 IPSWICH ELEVATION CUMULATIVE PERCENT 3 1.88 4 3.76 5 5.65 6 7.48 7 10.45 8 13.11 9 15.79 10 19.23 11 21.97 12 25.84 13 29.22 14 34.17 15 39.11 16 44.05 17 48.57 18 52.44 20 59.04 21 62.12 22 65.12 23 67.45 24 69.87 25 71.93 26 73.84 27 75.81 28 78.42 29 82.18 30 83.93 31 85.68 32 87.43 33 88.87 34 90.15 35 91.46 36 92.56 37 93.54 38 94.46 39 95.26 40 95.90 41 96.46 42 96.94 43 97.23 44 97.43 45 97.63 46 97.84 47 98.04 48 98.24 49 98.42 50 98.56 51 98.70 52 98.81 53 98.98 54 99.08 55 99.18 56 9930 57 99.36 58 99.42 59 99.47 60 99.84 A-64 IPSWICH HYPSOMETRY CALCULATED FOR UPLAND 3m.+ O - 0- D - , 0> ~~~~A -65 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-65 KINGSTON ELEVATION CUMULATIVE PERCENT 3 1.03 4 2.06 5 3.09 6 4.04 7 4.80 8 5.94 9 7.43 10 8.73 11 10.20 12 12.43 13 13.85 14 18.15 15 2238 16 26.60 17 30.82 18 34.53 19 37.86 20 41.04 21 44.09 22 47.02 23 49.80 24 52.22 25 54.13 26 55.80 27 57.42 28 58.81 29 60.28 30 62.33 31 64.38 32 66.43 33 67.98 34 69.50 35 70.79 36 71.96 37 73.17 38 74.45 39 7538 40 76.29 41 77.43 42 78.37 43 79.04 44 79.80 45 81.86 46 83.92 47 85.99 48 87.95 49 89.55 50 91.02 51 92.31 52 93.56 53 94.76 54 95.60 55 96.47 56 97.11 57 97.68 58 98.16 59 98.53 60 98.80 A-66 KINGSTON HYPSOMETRY CALCULATED FOR UPLAND 3m.+ o A- 67 O LYNN ELEVATION CUMULATIVE PERCENT 3 1.36 4 2.73 5 4.09 6 5.48 7 7.16 8 8.62 9 10.18 10 12.19 11 13.65 12 15.29 13 17.34 14 19.95 15 22.55 16 25.15 17 27.65 18 29.68 19 31.62 20 33.28 21 35.03 22 36.82 23 38.21 24 39.67 25 40.76 26 41.63 27 42.37 28 43.53 29 44.62 30 47.87 31 51.11 32 54.36 33 57.26 34 59.76 35 62.04 36 64.15 37 66.13 38 68.41 39 70.02 40 71.51 41 72.65 42 74.11 43 75.35 44 76.44 45 77.90 46 79.36 47 80.82 48 82.28 49 83.50 50 84.76 51 85.85 52 86.84 53 88.13 54 88.85 55 89.77 56 90.51 57 91.30 58 91.95 59 92.39 60 96.70 A-68 LYNN HYPSOMETRY CALCULATED FOR UPLAND 3m.+ 0- O - �'~ CO A-69 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-69 MANCHESTER ELEVATION CUMULATIVE PERCENT 3 0.79 4 1.57 5 2.36 6 2.98 7 4.00 8 4.65 9 5.70 10 7.11 11 8.42 12 10.22 13 12.87 14 19.36 15 25.84 16 32.33 17 38.09 18 43.04 19 47.33 20 51.56 21 55.52 22 59.25 23 62.43 24 65.87 25 68.56 26 71.01 27 73.47 28 76.32 29 79.79 30 81.56 31 83.33 32 85.10 33 86.73 34 88.27 35 89.68 36 90.76 37 92.07 38 92.96 39 93.97 40 94.63 41 95.41 42 95.97 43 96.66 44 97.28 45 9758 46 97.87 47 98.17 48 98.43 49 98.66 50 98.89 51 99.08 52 99.25 53 99.44 54 9957 55 99.67 56 99.74 57 99.80 58 99.87 59 99.90 60 100.00 A-70 MANCHESTER HYPSOMETRY CALCULATED FOR UPLAND 3m.+ 0 - r - 3/ 0- 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-71 MARBLEHEAD ELEVATION CUMULATIVE PERCENT 3 2.20 4 4.40 5 6.60 6 8.87 7 11.47 8 14.14 9 16.54 10 19.81 11 22.62 12 25.88 13 30.89 14 39.49 15 48.10 16 56.70 17 64.11 18 70.45 19 75.98 20 80.99 21 84.99 22 88.33 23 91.26 24 93.73 25 95.80 26 97.53 27 98.80 28 99.60 29 100.00 A-72 MARBLEHEAD HYPSO.METRY CALCULATED FOR UPLANI) .Sm.-t O z *~ c - O O - i O' _~~~~~~~~~~~.~ )O- I~~~~~~~~~~~~~~~~~~~~~~~~ O I F 0 10 20 :30 40 50 60 70 80 90 100 Percent of Upland Area .A-73 3 A-73~~~~~~~~~ MARION ELEVATION CUMULATIVE PERCENT 3 10.18 4 2036 5 30.54 6 36.95 7 42.83 8 48.50 9 54.93 10 59.12 11 62.82 12 67.22 13 70.19 14 73.23 15 76.23 16 79.23 17 82.22 18 84.97 19 87.35 20 9035 21 92.68 22 94.85 23 96.73 24 97.69 25 98.42 26 99.02 27 99.47 28 99.79 29 99.93 30 99.95 31 99.98 32 100.00 A-74 MARION HYPSOMETRY a CALCULATED FOR UPLAND 3m.-v 0: ~~~RI N ~~~~~~0 10 20 30 40 50 60 70 80 90 100 * ~~~~Percent of Upland Area 3 ~~~~~~~~~~A-75 MARSHFIELD ELEVATION CUMULATIVE PERCENT 3 1.38 4 2.76 5 4.14 6 5.53 7 7.38 8 932 9 11.95 10 1552 11 1835 12 21.96 13 25.54 14 32.52 15 35.68 16 38.83 17 41.99 18 44.52 19 46.91 20 48.98 21 51.24 22 53.12 23 54.85 24 56.59 25 58.09 26 59.38 27 60.73 28 62.12 29 63.68 30 65.81 31 67.95 32 70.08 33 71.88 34 73.62 35 75.27 36 76.72 37 78.23 38 79.44 39 80.57 40 81.71 41 82.65 42 83.62 43 8432 44 85.21 45 86.23 46 87.25 47 88.27 48 89.22 49 90.01 50 90.72 51 91.43 52 92.07 53 92.87 54 93.37 55 93.90 56 94.46 57 94.90 58 95.30 59 95.75 60 98.62 A-76 MARSHFIELD HYPSOMETRY CALCULATED FOR UPLAND 3m.� -/ I / 0.- 10- U Oo C- Q C) -\ - 7 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-77 MASHPEE ELEVATION CUMULATIVE PERCENT 3 3.32 4 6.65 5 9.97 6 12.42 7 14.79 8 17.12 9 20.18 10 22.57 11 24.80 12 30.72 13 33.43 14 36.82 15 43.51 16 50.19 17 56.87 18 61.36 19 65.03 20 68.61 21 71.53 22 74.00 23 76.46 24 78.42 25 80.20 26 81.85 27 83.37 28 84.48 29 85.55 30 87.31 31 89.07 32 90.82 33 92.43 34 93.90 35 95.09 36 96.15 37 97.10 38 97.92 39 98.52 40 99.01 41 99.41 42 99.70 43 99.91 44 100.00 A-78 M-4ASH'PEE EJYPSOMETRY CALCULATED FOR UPLAND 3m.v I~ nc E~ I ~CQ *~~ 2- 7 - IIIII.111I II I III~II II)IIIIII IIIIII.II) I .IIIII I I1II1tII1aIII II 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-79 MATTAPOISETT ELEVATION CUMULATIVE PERCENT 3 4.04 4 8.08 5 12.11 6 1532 7 18.63 8 22.63 9 27.70 10 31.18 11 34.78 12 39.51 13 42.91 14 46.68 15 51.28 16 55.89 17 60.49 18 64.37 19 67.56 20 70.94 21 73.56 22 76.59 23 8757 24 91.46 25 94.12 26 95.84 27 97.36 28 98.16 29 98.78 30 98.92 31 99.06 32 99.20 33 99.33 34 99.43 35 9954 36 99.63 37 99.72 38 99.79 39 99.84 40 99.89 41 99.93 42 99.96 43 99.98 44 100.00 A-80 MAX'TAPOISETT HYPSOMETRY CALCULATED FOR UPLAND 3m.+ O_ * o o O 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-81 NAHANT ELEVATION CUMULATIVE PERCENT 3 6.08 4 12.16 5 18.24 6 2432 7 32.09 8 39.86 9 45.27 10 53.72 11 58.11 12 65.88 13 68.58 14 71.96 15 75.34 16 78.72 17 81.76 18 84.46 19 87.16 20 89.53 21 91.55 22 93.58 23 95.27 24 96.62 25 97.64 26 98.65 27 99.32 28 99.66 29 100.00 A-82 NAHANT HYPSOMETRY CALCULATED FOR UPLAND 3m.+ 0- tO - ,- cUD - - CO I- ll tl llI lltlll JBIIl ,,ll l lllll lll,111,l,11 J IllIl ll Illlllllll lll IlllJ 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-83 NANTUCKET ELEVATION CUMULATIVE PERCENT 3 8.70 4 17.40 5 26.10 6 32.11 7 37.66 8 42.86 9 52.04 10 56.58 11 60.40 12 65.56 13 69.22 14 72.83 15 76.41 16 79.98 17 83.55 18 86.52 19 89.13 20 91.49 21 93.31 22 94.81 23 96.20 24 97.29 25 98.12 26 98.77 27 9930 28 99.65 29 99.82 30 99.84 31 99.86 32 99.88 33 99.91 34 99.93 35 99.94 36 99.95 37 99.97 38 99.98 39 99.99 40 99.99 A-84 NAN T UCLEL L 1 I , HY 'tLVl PIO Ei CALCULATED FOFR UTPLAND 3n.+ CD - I~ co O0- o t.O - I- 5~~~~~~~ &g e o - o- I~~~~~~~ o~. 02 - I~~~~~~~ 3, > . ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~// X.-2 - - 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland .Area A-85 NEW BEDFORD ..................................................... ELEVATION CUMULATIVE PERCENT 3 1.89 4 3.78 5 5.67 6 6.99 7 8.03 8 9.14 9 10.42 10 11.37 11 12.30 12 13.58 13 14.39 14 14.99 15 16.03 16 17.08 17 18.12 18 23.22 19 26.52 20 31.66 21 39.77 22 41.67 23 44.76 24 50.42 25 52.88 26 55.65 27 59.25 28 62.20 29 65.03 30 68.34 31 71.65 32 74.97 33 77.81 34 81.14 35 83.65 36 85.86 37 88.26 38 89.91 39 91.35 40 92.86 41 94.55 42 95.48 43 9638 44 97.04 45 97.35 46 97.67 47 97.99 48 98.28 49 98.55 50 98.79 51 99.02 52 99.21 53 99.39 54 99.55 55 99.68 56 99.79 57 99.88 58 99.94 59 99.98 60 100.00 A-86 NEW BEDFORtD HYPSOMETRY CALCULATED FOR UPLAND 3m.+ 0- 0o i_ O . - UI "0 10 20 30 40 50 60 70 80 90 100 *i~ ~Percent of Upland Area A-87 NEWBURY ELEVATION CUMULATIVE PERCENT 3 2.83 4 5.65 5 8.48 6 10.97 7 14.97 8 18.76 9 22.60 10 27.49 11 31.98 12 37.35 13 43.08 14 48.89 15 54.69 16 60.49 17 66.11 18 70.59 19 74.86 20 78.50 21 82.16 22 85.33 23 88.11 24 90.74 25 92.77 26 94.46 27 95.86 28 97.04 29 98.14 30 98.34 31 9g.54 32 98.74 33 98.90 34 99.05 35 99.24 36 99.37 37 99.48 38 99.58 39 99.67 40 99.75 41 99.82 42 99.87 43 99.90 44 99.92 45 99.93 46 99.95 47 99.97 48 99.98 49 100.00 A-88 NEWBURY HYPSOMETRY CALCULATED FOR UPLAND 3m.+ o Oo - - 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-89 NEWBURYPORT ELEVATION CUMULATIVE PERCENT 3 1.50 4 3.00 5 4.50 6 5.27 7 6.44 8 8.34 9 10.48 10 15.32 11 20.82 12 27.96 13 36.37 14 42.78 15 49.18 16 55.59 17 61.39 18 65.83 19 70.00 20 73.87 21 77.44 22 81.11 23 83.85 24 86.49 25 88.92 26 -91.06 27 92.86 28 94.63 29 96.43 30 96.83 31 97.23 32 97.63 33 98.00 34 98.33 35 98.63 36 98.90 37 99.13 38 99.33 39 99.50 40 99.67 41 99.80 42 99.90 43 99.97 44 100.00 A-90 NEWBURYPORT HYPSOMETRY CALCULATED FOR UPLAND 3m.+ I O - 0- . o 0- :,-j~i E -I 0 10 20 30 40 50 60 70 80 90 O00 * Percent of 'Upland Area 3 A-91 OAK BLUFFS ELEVATION CUMULATIVE PERCENT 3 450 4 9.01 5 13.51 6 16.88 7 20.32 8 2336 9 26.88 10 29.66 11 31.86 12 35.15 13 37.13 14 39.25 15 42.40 16 45.55 17 48.70 18 52.22 19 55.14 20 59.17 21 61.59 22 64.52 23 68.33 24 74.11 25 77.77 26 80.48 27 8334 28 85.46 29 87.15 30 88.58 31 90.00 32 91.43 33 92.75 34 93.96 35 95.06 36 96.05 37 96.92 38 97.69 39 98.35 40 98.90 41 99.34 42 99.67 43 100.00 A-92 CALCULATED FOR UPL-AND Pn 0: (0- 0- I i~~C I /~~C o0� A-93- ORLEANS ELEVATION CUMULATIVE PERCENT 3 5.68 4 11.36 5 17.04 6 21.67 7 25.99 8 30.39 9 36.05 10 39.70 11 43.49 12 46.94 13 50.63 14 54.46 15 59.84 16 65.21 17 70.58 18 74.98 19 78.95 20 82.55 21 85.65 22 88.05 23 90.43 24 92.38 25 93.94 26 95.40 27 96.70 28 97.57 29 98.11 30 98.39 31 98.67 32 98.95 33 99.16 34 99.28 35 99.44 36 99.54 37 99.69 38 99.80 39 99.87 40 99.92 41 99.95 42 99.97 43 100.00 A-94 ORLEANS HYPSOMETRY CALCULATED FOR UPLAND 3m.+ o C) n _ CQ - ) Cu- 3J O :_ CO - ,,,,,,,,,,,,,I IIII11 llllll l llllllll IIII llllllllll lllll ll lllll lll 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-95 PLYMOUTH ELEVATION CUMULATIVE PERCENT 3 0.44 4 0.89 5 1.33 6 2.02 7 2A7 8 2.91 9 3.56 10 4.07 11 4.67 12 5.53 13 6.26 14 8.15 15 9.95 16 11.75 17 13.55 18 15.16 19 16.77 20 18.68 21 20.32 22 21.72 23 23.32 24 25.52 25 26.99 26 28.40 27 30.36 28 31.93 29 33.82 30 37.22 31 40.62 32 44.02 33 47.01 34 50.41 35 53.23 36 56.12 37 59.72 38 61.87 39 63.75 40 65.52 41 67.48 42 68.82 43 70.05 44 71.14 45 73.51 46 75.88 47 78.25 48 80.53 49 82.36 50 84.02 51 85.57 52 87.03 53 88.26 54 89.33 55 90.46 56 91.33 57 92.05 58 92.70 59 93.36 60 94.03 A-96 PLYMOUTH HYPSOMETRY CALCULATED FOR UPLAND 3m.+ O 0- o _ o- 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area iA- 97 -- / A- 97 PROVINCETOWN ELEVATION CUMULATIVE PERCENT 3 5.89 4 11.78 5 17.67 6 2236 7 2851 8 33.60 9 38.82 10 43.78 11 46.99 12 49.40 13 53.01 14 57.97 15 62.92 16 67.87 17 72.42 18 76.71 19 8059 20 84.07 21 87.28 22 90.09 23 92.50 24 94.65 25 9639 26 97.86 27 98.93 28 99.60 29 100.00 A-98 PROVINCETOWN HYPSOMETRY CALCULATED FOR UPLAND 3m.t o CD o 3 A-99 O - 'q CO - V �z- 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-99 QUINCY ELEVATION CUMULATIVE PERCENT 3 3.41 4 6.82 5 10.22 6 12.93 7 16.07 8 18.77 9 21.29 10 24.07 11 26.50 12 29.00 13 31.37 14 33.77 15 36.16 16 38.56 17 41.01 18 43.29 19 45.41 20 47.17 21 48.67 22 50.46 23 52.02 24 53.59 25 54.66 26 55.56 27 56.57 28 57.53 29 58.11 30 59.08 31 60.06 32 61.03 33 61.71 34 62.41 35 63.37 36 64.28 37 64.93 38 65.63 39 66.47 40 67.07 41 67.63 42 68.51 43 69.09 44 70.01 45 71.14 46 72.27 47 73.40 48 74.47 49 75.46 50 76.44 51 7739 52 7833 53 7932 54 79.92 55 80.76 56 81.73 57 82.26 58 83.19 59 83.89 60 8738 A-100 QUINCY HYPSOMETRY CALCULATED FOR UPLAND 3m t 0- O - 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area 3'oA-101 A-101 REHOBOTH ELEVATION CUMULATIVE PERCENT 3 0.91 4 1.81 5 2.72 6 3.37 7 4.15 8 5.19 9 6.70 10 7.69 11 8.62 12 9.81 13 10.68 14 11.55 15 12.68 16 13.82 17 14.95 18 16.28 19 17.77 20 20.05 21 21.70 22 23.30 23 25.55 24 27.58 25 29.62 26 32.06 27 35.32 28 37.89 29 41.14 30 43.90 31 46.66 32 49.42 33 52.07 34 55.14 35 57.86 36 64.60 37 73.52 38 76.09 39 78.33 40 80.46 41 82.84 42 84.24 43 8538 44 86.40 45 87.12 46 87.85 47 88.57 48 8950 49 90.18 50 90.72 51 9136 52 92.16 53 92.82 54 93.41 55 94.24 56 94.87 57 9555 58 96.22 59 97.12 60 98.07 A-102 REHOBOTH HYPSOMETRY CALCULATED FOR UPLAND 3m.+ 0 O - O _ I oj CO3 1'11 1 111l1tI I Hil I I II I II 1111 1111 111111 1 1111111 II II I I I no II I III II I 1 olI II 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-103 REVERE ELEVATION CUMULATIVE PERCENT 3 3.02 4 6.05 5 9.07 6 12.10 7 17.36 8 21.17 9 25.83 10 31.94 11 37.69 12 44.46 13 51.42 14 55.17 15 58.92 16 62.67 17 66.73 18 70.05 19 73.14 20 76.29 21 79.43 22 81.67 23 83.85 24 86.15 25 88.08 26 89.96 27 90.74 28 91.59 29 92.20 30 92.92 31 93.65 32 9437 33 94.80 34 95.40 35 96.01 36 96.49 37 96.85 38 97.28 39 97.70 40 98.06 41 98.61 42 98.67 43 98.73 44 98.85 45 98.97 46 99.09. 47 99.21 48 99.33 49 99.46 50 99.58 51 99.64 52 99.70 53 99.76 54 99.82 55 99.88 56 99.94 A-1 04 REVERE HYPSOMETRY CALCULATED FOR UPLAND 3m.+ o 0 -0 tO 0 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-105 ROCKPORT ELEVATION CUMULATIVE PERCENT 3 1.27 4 2.54 5 3.80 6 5.16 7 7.19 8 8.41 9 9.97 10 11.71 11 13.02 12 14.24 13 15.89 14 18.09 15 21.13 16 24.18 17 27.22 18 29.29 19 31.66 20 33.73 21 36.09 22 37.66 23 39.56 24 41.50 25 43.03 26 44.76 27 46.03 28 47.93 29 50.30 30 54.31 31 58.33 32 62.34 33 65.89 34 69.10 35 72.15 36 74.77 37 77.26 38 79.25 39 81.49 40 83.43 41 84.66 42 86.01 43 86.90 44 87.87 45 89.26 46 90.66 47 92.05 48 93.20 49 94.63 50 95.56 51 96.41 52 97.13 53 97.93 54 98.39 55 98.86 56 99.11 57 99.32 58 99.62 59 99.75 60 100.00 A-106 ROCKPORT HYPSOMETRY CALCULATED FOR UPLAND 3m.+ O co O - O_0 E - CO - 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-107 ROWLEY ELEVATION CUMULATIVE PERCENT 3 0.60 4 1.20 5 1.79 6 2.60 7 350 8 4.51 9 5.42 10 6.44 11 7.40 12 8.67 13 9.98 14 11.91 15 17.66 16 23.40 17 29.15 18 34.02 19 38.68 20 43.09 21 4752 22 51.42 23 55.35 24 59.06 25 62.68 26 66.43 27 70.72 28 75.42 29 79.61 30 81.59 31 83.57 32 85.56 33 87.30 34 88.89 35 90.38 36 91.71 37 92.92 38 94.05 39 94.94 40 95.73 41 9631 42 96.82 43 97.23 44 97.45 45 97.66 46 97.86 47 98.07 48 98.17 49 98.34 50 98.55 51 98.62 52 98.74 53 98.84 54 98.92 55 98.99 56 99.08 57 99.15 58 99.21 59 99.25 60 99.61 A-108 ROWLEY HYPSOMETRY CALCULATED FOR UPLAND 3m.t o 0-- cr: o O- 0 10 20 30 40 50 60 70 80 90 100o Percent of Upland Area A-109 SALEM ELEVATION CUMULATIVE PERCENT 3 238 4 4.76 5 7.14 6 933 7 12.14 8 14.52 9 16.43 10 18.93 11 21.39 12 24.33 13 2730 14 31.27 15 35.20 16 39.13 17 43.06 18 46.90 19 49.84 20 52.54 21 55.20 22 57.42 23 59.40 24 61.35 25 62.90 26 64.56 27 65.87 28 67.26 29 68.37 30 70.95 31 73.53 32 76.11 33 78.33 34 8036 35 82.22 36 83.89 37 85.36 38 86.71 39 88.02 40 89.05 41 90.00 42 91.07 43 92.22 44 93.33 45 94.01 46' 94.68 47 95.36 48 96.03 49 96.67 50 97.26 51 97.74 52 98.17 53 98.57 54 98.97 55 99.25 56 99.48 57 99.68 58 99.84 59 99.92 60 99.96 A-1 10 SALEM HYPSOMETRY CALCULATED FOR UPLAND 3m.+ o 0O C- of Upland Area * A-111 o O-: 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-111 1 SALISBURY ELEVATION CUMULATIVE PERCENT 3 438 4 8.76 5 13.14 6 17.16 7 22.05 8 26.65 9 30.73 10 35.41 11 39.08 12 4330 13 47.48 14 52.44 15 57.41 16 6237 17 67.26 18 70.72 19 74.41 20 77.39 21 80.83 22 83.25 23 85.46 24 87.68 25 89.31 26 90.81 27 92.08 28 93.05 29 93.76 30 94.50 31 95.24 32 95.98 33 96.36 34 96.77 35 97.20 36 97.56 37 97.84 38 98.01 39 9832 40 98.55 41 98.73 42 98.91 43 99.03 44 99.08 45 99.13 46 99.19 47 99.24 48 99.34 49 99.47 50 99.52 51 99.57 52 99.59 53 99.67 54 99.69 55 99.72 56 99.75 57 99.80 58 99.80 59 99.85 60 100.00 A-1 12 SALISBUREY HYPSOMETRY CALCULATED FOR UPLAND 3m.+ I) A- 0 10 20 30 40 50 - 70 80 90 100 I> : A-113 SANDWICH ELEVATION CUMULATIVE PERCENT 3 1.61 4 3.22 5 4.83 6 6.03 7 7.15 8 8.06 9 9.17 10 10.01 11 10.84 12 11.77 13 12.39 14 13.11 15 13.88 16 14.66 17 15.43 18 16.12 19 16.72 20 17.26 21 17.83 22 18.34 23 19.09 24 19.83 25 20.41 26 21.13 27 22.22 28 22.96 29 24.04 30 27.26 31 30.48 32 33.70 33 36.36 34 39.46 35 41.86 36 44.07 37 46.65 38 51.67 39 53.56 40 55.19 41 56.93 42 58.26 43 59.51 44 60.81 45 63A5 46 66.10 47 68.74 48 7130 49 73.28 50 75.14 51 76.92 52 78.97 53 80.55 54 82.19 55 83.93 56 85.28 57 86.66 58 87.98 59 89.51 60 90.84 A-114 SANDWICH HYPSOMETRY CALCULATED FOR UPLAND 3m.t Lo CD o O - 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-115 A-1-15 SAUGUS ELEVATION CUMULATIVE PERCENT 3 0.75 4 150 5 2.25 6 3.51 7 5.06 8 5.92 9 7.29 10 9.11 11 10.40 12 12.62 13 15.03 14 18.76 15 22.96 16 27.17 17 3138 18 34.67 19 38.08 20 41.43 21 44.86 22 47.35 23 5038 24 53.51 25 56.30 26 59.08 27 6133 28 64.17 29 67.23 30 69.53 31 71.84 32 74.14 33 7637 34 7832 35 80.31 36 82.13 37 83.57 38 85.16 39 86.28 40 87.49 41 88.64 42 89.44 43 90.22 44 90.89 45 91.56 46 92.23 47 92.90 48 93.65 49 94.40 50 94.96 51 95.50 52 96.03 53 96.54 54 97.13 55 97.62 56 98.12 57 98.42 58 98.82 59 99.01 A-1 16 SAUGUS HYPSOMETRY CALCULATED FOR UPLAND 3m.o 0- : / O- / O - 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A- 17 SCITUATE ELEVATION CUMULATIVE PERCENT 3 1.44 4 2.87 5 431 6 5.67 7 736 8 8.87 9 10.27 10 12.05 11 13.59 12 15.08 13 17.02 14 21.85 15 26.68 16 31.51 17 35.98 18 40.09 19 43.75 20 47.07 21 50.50 22 53.36 23 56.07 24 58.78 25 61.31 26 63.64 27 65.66 28 67.97 29 7034 30 74.00 31 77.67 32 81.33 33 84.40 34 87.13 35 89.62 36 91.63 37 93.23 38 94.74 39 95.96 40 97.00 41 97.88 42 98.55 43 98.98 44 9939 45 99.44 46 99.50 47 99.55 48 99.64 49 99.71 50 99.77 51 99.80 52 99.87 53 99.91 54 99.93 55 99.95 56 99.96 57 99.98 58 100.00 A-118 SCITUATE HYPSOMETRY CALCULATED FOR UPLAND 3rm.+ 0- OO 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-119 SEEKONK ELEVATION CUMULATIVE PERCENT 3 0.27 4 0.55 5 0.82 6 1.07 7 1.62 8 2.17 9 3.42 10 4.35 11 5.45 12 7.39 13 9.10 14 10.90 15 13.73 16 16.56 17 19.39 18 21.99 19 25.21 20 29.95 21 34.67 22 39.26 23 45.21 24 49.56 25 53.56 26 57.40 27 62.55 28 66.58 29 70.50 30 72.80 31 75.09 32 77.38 33 79.57 34 82.24 35 84.56 36 86.58 37 88.57 38 90.46 39 92.24 40 93.82 41 95.17 42 96.00 43 96.65 44 97.16 45 97.38 46 97.60 47 97.82 48 98.08 49 98.28 50 98.49 51 98.63 52 98.81 53 99.00 54 99.08 55 99.26 56 99.37 57 99.46 58 99.53 59 99.66 60 99.70 A-120 SEEKONK HYPSOMETRY CALCULATED FOR UPLAND 3m.+ to 0- O * ~~Percent of Upland Area A-121 A-121 SOMERSET ELEVATION CUMULATIVE PERCENT 3 3.60 4 7.20 5 10.81 6 13.28 7 15.68 8 18.09 9 20.83 10 2330 11 25.18 12 2833 13 30.47 14 3257 15 35.01 16 37.45 17 39.89 18 41.73 19 43.56 20 46.08 21 47.84 22 49.57 23 51.93 24 53.96 25 55.68 26 57.64 27 60.23 28 62.29 29 64.43 30 71.71 31 78.99 32 86.27 33 90.81 34 93.13 35 94.37 36 95.50 37 96.51 38 9737 39 98.12 40 98.76 41 99.25 42 99.62 43 99.89 44 100.00 A-122 SOMERSET HYPSOMETRY CALCULATED FOR UPLAND 3m.+ QO: o - Oo- oN_ X - 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-123 SWAMPSCOTT ELEVATION CUMULATIVE PERCENT 3 1.79 4 3.58 5 5.37 6 6.26 7 8.86 8 10.65 9 13.25 10 16.42 11 19.19 12 22.11 13 26.26 14 30.49 15 34.72 16 38.94 17 43.25 18 47.56 19 50.73 20 53.82 21 57.64 22 60.81 23 63.50 24 66.02 25 68.21 26 70.81 27 72.76 28 75.20 29 78.78 30 80.98 31 83.17 32 85.37 33 87.48 34 89.35 35 91.22 36 92.85 37 94.23 38 95.53 39 96.67 40 97.64 41 98.37 42 98.94 43 99.43 44 99.59 45 99.67 46 99.76 47 99.84 48 99.92 49 100.00 A-124 SWAMPSCOTT HYPSOMETRY CALCULATED FOR UPLAND 23m.+ crQ I O- I - 0- C OX 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-125 SWANSEA ELEVATION CUMULATIVE PERCENT 3 2.22 4 4.44 5 6.65 6 8.60 7 10.53 8 12.56 9 15.58 10 17.76 11 20.25 12 23.90 13 26.60 14 29.23 15 31.54 16 33.84 17 36.15 18 39.12 - 19 42.29 20 45.99 21 48.71 22 51.53 23 54.99 24 57.67 25 59.94 26 61.77 27 64.14 28 66.40 29 68.95 30 72.45 31 75.95 32 79.45 33 82.99 34 87.39 35 90.47 36 93.10 37 96.22 38 97.92 39 98.94 40 99.34 41 99.63 42 99.81 43 99.94 44 100.00 A-126 SWANSEA HYPSOMETRY CALCULATED FOR UPLAND 3m.+ O CO Oo- 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-127 TISBURY ELEVATION CUMULATIVE PERCENT 3 3.82 4 7.63 5 11.45 6 14.11 7 16.81 8 18.81 9 21.69 10 23.96 11 26.09 12 28.39 13 29.64 14 30.43 15 33.98 16 37.53 17 41.08 18 44.19 19 47.29 20 50.89 21 53.68 22 55.95 23 59.27 24 65.35 25 67.61 26 70.41 27 72.89 28 74.98 29 76.97 30 79.59 31 82.21 32 84.83 33 87.22 34 89.35 35 91.35 36 92.90 37 94.63 38 95.96 39 97.03 40 97.96 41 98.80 42 99.33 43 99.69 44 99.87 45 99.91 46 99.96 47 100.00 A-128 TJSI3LF B HYPSOMETEfY H ~CALCULATED FOR UPLAND -3nrit- I _ _ _ _ _ _ _ 0: CD: 0- ~ ~~~~~~-2 TRURO ELEVATION CUMULATIVE PERCENT 3 1.86 4 3.72 5 5.57 6 7.21 7 8.81 8 10.22 9 11.86 10 13.25 11 14.92 12 16.25 13 17.81 14 21.76 15 26.18 16 30.60 17 34.49 18 38.39 19 41.48 20 '44.80 21 47.99 22 50.77 23 5334 24 5552 25 57.83 26 59.79 27 6153 28 63.48 29 65.67 30 69.09 31 72.52 32 75.94 33 78.98 34 81.48 35 84.09 36 86.16 37 88.26 38 90.08 39 91.75 40 93.15 41 9434 42 95.42 43 96.20 44 97.10 45 97.41 46 97.72 47 98.03 48 9830 49 98.55 50 98.80 51 99.02 52 99.21 53 99.39 54 99.53 55 99.66 56 99.78 57 99.87 58 99.93 59 99.97 A-130 TRURO HYPSOMETRY CALCULATED FOR UPLAND 3m.t I CO - - � 0- X 2- 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-131 WAREHAM ELEVATION CUMULATIVE PERCENT 3 7.77 4 15.54 5 2331 6 27.16 7 30.52 8 33.68 9 37.52 10 40.63 11 44.41 12 48.89 13 52.61 14 57.41 15 62.58 16 67.76 17 72.93 18 81.54 19 81.54 20 85.80 21 88.83 22 9133 23 93.53 24 95.69 25 97.04 26 98.09 27 98.91 28 99.44 29 99.71 30 99.75 31 99.78 32 99.81 33 99.84 34 99.86 35 99.89 36 99.91 37 99.93 38 99.94 39 99.96 40 99.98 41 99.98 42 99.99 A-132 WAREHAM HYPSOMETRY CALCULATED FOR UPLAND 3m.+ O1- oE8- I O o Percent of Upland Area A- 133 WELLFLEET ELEVATION CUMULATIVE PERCENT 3 3.64 4 7.28 5 10.92 6 14.14 7 16.96 8 19.79 9 24.08 10 27.42 11 30.88 12 42.18 13 46.08 14 50.66 15 55.75 16 60.83 17 '65.91 18 70.98 19 74.93 20 78.88 21 82.05 22 85.05 23 87.95 24 90.22 25 92.13 26 93.65 27 95.07 28 96.08 29 96.76 30 97.13 31 97.49 32 97.86 33 98.19 34 98.49 35 98.76 36 99.01 37 99.22 38 99.41 39 99.58 40 99.72 41 99.83 42 99.90 43 99.97 A-134 WELLFLEET HYPSOMETRY CALCULATED FOR UPLAND 3m�+ CD * C- * . 0 - - 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-135 WESTPORT ELEVATION CUMULATIVE PERCENT 3 1.34 4 2.69 5 4.03 6 5.03 7 6.09 8 7.09 9 8.46 10 9.45 11 10.49 12 11.80 13 12.86 14 13.85 15 15.15 16 16.46 17 17.77 18 19.12 19 20.36 20 22.09 21 23.31 22 24.65 23 26.33 24 27.74 25 29.15 26 3057 27 32.57 28 34.52 29 36.42 30 40.14 31 43.86 32 47.58 33 50.83 34 54.28 35 56.58 36 58.63 37 61.09 38 62.93 39 64.72 40 67.80 41 71.22 42 72.84 43 74.68 44 76.86 45 78.36 46 79.86 47 81.35 48 82.85 49 84.12 50 85.15 51 86.10 52 8730 53 88.26 54 89.18 55 90.21 56 90.99 57 91.81 58 92.60 59 93.60 60 94.46 A-136 WESTPORT HYPSOMETRY CALCULATED FOR UPLAND 3mv+ - OD- 0-_ . A-137 0 102-0 4 0 60 7 0 9 0 *~ Pecn fUpadAe WEST TISBURY ELEVATION CUMULATIVE PERCENT 3 2.03 4 4.06 5 6.09 6 7.71 7 937 8 10.97 9 21A3 10 23.55 11 2535 12 27.58 13 29.29 14 30.89 15 33.51 16 36.14 17 38.77 18 41.23 19 43A8 20 46.60 21 49.02 22 5139 23 54.29 24 59.17 25 62.09 26 64.88 27 68.35 28 70.81 29 73.33 30 74.85 31 76.37 32 77.89 33 79.29 34 80.76 35 81.99 36 83.12 37 84.48 38 85.32 39 86.31 40 87.16 41 88.13 42 88.78 43 89.43 44 89.96 45 90.64 46 9133 47 92.01 48 92.73 49 93.23 50 93.73 51 94.11 52 94.64 53 95.00 54 95.42 55 95.83 56 96.16 57 96.57 58 96.84 59 97.21 60 97.54 A-138 WEST TISDBUBtY HYPSOMlE tRY CALC(ULATED FOR UPLAND 3n.+ O / CO- 7" O., I I i i''' I I I I I III I I T I I I.I I III II II 0 10 20 30 40 50 60 70 80 ',0 100 Percent of Upland Area A-139 WEYMOUTH ELEVATION CUMULATIVE PERCENT 3 0.47 4 0.95 5 1.42 6 1.83 7 2.51 8 2.95 9 357 10 439 11 5.18 12 6.09 13 7.20 14 8.75 15 10.29 16 11.84 17 13.45 18 14.68 19 16.04 20 17.27 21 18.25 22 19.45 23 2052 24 21.69 25 22.64 26 23.79 27 24.87 28 26.48 29 28.35 30 31.42 31 34.48 32 37.54 33 40.21 34 42.47 35 44.73 36 46.61 37 48.34 38 49.92 39 51.36 40 52.64 41 53.65 42 54.83 43 55.60 44 56.36 45 59.87 46 63.37 47 66.88 48 71.38 49 75.21 50 78.69 51 82.66 52 86.25 53 89.64 54 92.04 55 94.38 56 96.51 57 97.92 58 98.88 59 99.49 60 100.00 ;A-140 WEYMOUTH HYPSOMETRY CALCULATED FOR UPLAND 3m.+ o oi/ Percent of Upland Area m*-* /~~~~A-41 U 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area WINTHROP ELEVATION CUMULATIVE PERCENT 3 6.81 4 13.61 5 20.42 6 26.70 7 32.46 8 41.88 9 45.55 10 52.36 11 58.64 12 65.45 13 73.82 14 76.44 15 79.06 16 81.68 17 84.29 18 86.91 19 89.01 20 91.10 21 92.67 22 94.24 23 95.81 24 96.86 25 97.91 26 98.95 27 99.48 28 100.00 A-142 W tIN'THROP HYPSOMETRY' CALCULAT'ED FOR UPLAND 3m.-+ c( - 0 ,-, o -~~~A-143 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-143 YARMOUTH ELEVATION CUMULATIVE PERCENT 3 8.40 4 16.81 5 25.21 6 32.32 7 40.52 8 49.99 9 55.45 10 59.63 11 63.44 12 67.91 13 71.44 14 75.32 15 77.79 16 80.26 17 82.73 18 84.93 19 86.91 20 88.93 21 90.46 22 91.95 23 94.62 24 94.62 25 95.61 26 96.46 27 97.38 28 98.10 29 98.58 30 98.76 31 98.94 32 99.11 33 99.27 34 99.38 35 99.51 36 99.61 37 99.70 38 99.77 39 99.84 40 99.89 41 99.92 42 99.96 43 99.99 44 100.00 A-144 YARMOUTH HYPSOMETRY CALCULATED FOR UPLAND 3m.+ O O o 0 1 * C i,,,,,,,,, ,,,,,,,,,l,,,,,,,,,l,, l l l l 1 1 1 0 10 20 30 40 50 60 70 80 90 100 Percent of Upland Area A-1 45 APPENDIX B Software Guide for Massachusetts Hypsometry Data Base Processing This document outlines the two methodologies used by the Woods Hole Oceanographic Institution (WHOI) to generate digital and graphical products that define the hypsometry of coastal Massachusetts. Two avenues of data generation and analysis were created in this project, each described in a distinct section below. Part one: To analyze a large-scale, statewide data base, software was written to reduce and compile the Digital Elevation Model (DEM) with census and landcover data generated by the Defense Mapping Agency (DMA) and distributed by the United States Geological Survey (USGS.). In general, this process involves reformatting and regridding of the landcover and census data (so that it can be meshed with the DEM, and partitioned into town-scale subsets). Part two: For a more quantitative areal representation of local hypsometry and shoreline retreat resulting from relative sea-level rise, smaller, more detailed data bases were generated at WHOI. These data were derived from the USGS topographic quadrangle sheets, and have been processed to yield a more detailed and complete digital elevation model of three Massachusetts harbors. Much of the following information includes specific references to program and data file name conventions that, while not important in and of themselves, are useful as direct references to the software library at the laboratory. A. DATA STORAGE/DIRECTORY STRUCTURE [PES.HYP] All software is stored, edited and debugged in this directory. Software may be executed in this directory or others. B-1 [PES.DIGDAT] All digitizer output is stored here, as are the reformatted versions of the various data files. Reformatting can be executed here or in .HYP with inputs and outputs designated with [-.DIGDAT] preceding filename. [PES.HYPDAT] All individual town hypsometry data sets are stored here; all are named with a '.LIS' extension. These files also may be generated with an executable file stored in .HYP or one copied into this directory. [PES.HYPDAT.TABLE] All the tables associated with individual town hypsometry data sets are stored here. All are named with a '.TAB' extension. [PES.HYPDAT.PLOTS] All the plot files associated with the town hypsometry data sets are stored here. All are named with a '.PLT' extension. B. PART ONE: STATE-WIDE HYPSOMETRY BY TOWN 1.) DATA BASE A. The DEM data is in one-degree squares at 3 second intervals stored as south-to-north profiles. Elevations are to the nearest meter, formatted as follows: * (8) 1024-byte virtual records making up a 8192-byte physical block. Only thefirst 1020 bytes of each virtual record contain data. - Thefirst block contains header information in the first and part of the second record - Other Blocks: Ist record-- 210 bytes (35 values in 6-bytefields) that are part of the previous profile 2nd record-- 144 bytes of header for the next profile and 876 bytes (146 values) of data. Thefirst profile of the data set starts at this point in the first block. 3rd-8th record-- 1020 bytes (170 values) of data each. Each value is six bytes. B-2 B. Land use, land cover, and political unit data sets cover the area of a USGS 1:250,000 scale map, and lie along west-to-east rows at 200 meter intervals on the UTM grid. The UTM grid is rotated counterclockwise just slightly with respect to longitude, yet bounded by the latitude boundaries of the USGS maps. Consequently some rows are shorter because they either run into the northern longitude bound or start along the southern longitude bound. These data are multiplexed and structured into 80-character records blocked into groups of 102 data points. The blocksize is 8160 bytes. The beginning and end of a block are unrelated to the beginning or end of a row. Each record contains the UTM coordinates to locate the point that it describes. This portion of the data base is hereafter referred to as the 'GRIDCELL' data as well. 2.) COORDINATE TRANSLATION In order to locate the elevation data with respect to political units and land types (beaches, ponds, lakes, rivers being areas of special interest) the two data sets must be overlayed. To locate the land cover, etc. data with respect to the Lat./Long. system the United States Geological Survey (USGS) translated all the UTM coordinate pairs to Lat/Long values. OUTPUT FORMATS USED BY USGS For both the Boston and Providence data sets the translated Lat/Long coordinates that located each record were output separately (onto magnetic tape) maintaining the blocking factor of 102. We then merged (MERGEV3.FOR, MERGEV4A.FOR) these data with the appropriate fields from the original tape, creating 5100-byte blocks that contain 102 data points. Version 3 of MERGE handles the format used with the Providence sheet; version 4A handles the slightly different Boston sheet format. Each block of this new data set is made up of 102 50-byte virtual records. Each record contains ten bytes each for Latitude, Longitude, Land Cover Code, State/County Code, and Town (census) Code. 3.) REGRIDDING DATA NOTE: GRDMATV3.FOR is for Providence data; GRDMATV4A.FOR is for Boston data. Input formats are the same, but data peculiarities necessitated customized error handling routines. Once all the data describing each point in terms of land cover, political unit, and Lat/Long position were assembled on one tape, a new matrix was created that has data arranged on a grid identical to the DEM grid. GRDMATV3/V4A.FOR uses a simple method to create this DEM- based matrix of land and political codes. Essentially the software travels from point-to-point through an empty 3-second Lat/Long grid and searches for the closest data point in the UTM B-3 GRIDCELL system, assigning the values associated with that point to its current location. It only examines the eight points surrounding the previous closest point found. Because the 200 meter UTM interval is about twice that of the 3-second DEM interval, this limited search field always contains the closest point. The GRIDCELL data are first put into an array of 600 by 900 points. Spatial organization is maintained by padding the input data stream with leading and trailing spaces to preserve the row length of 900 points. The partial rows at the beginning and end of the data set are aligned by their longitude values. Longitude and latitude values are used to tag data errors, end of row, and leading space conditions. Most bad data points are eliminated and new ones interpolated from surrounding values. This matrix is filled left-to-right/north-to-south according to the order in which the GRIDCELL data are stored. Then the closest-point interpolation routine examines the data in north-to-south columns compatible with the DEM grid of 3-second intervals, starting in the NW corner. As each column is filled it is written to a magnetic storage tape. This is the only point during the data reduction process that any information is stored as unformatted data. These data rows now merely must be inverted in order to match the DEM format. User input determines the starting point for the interpolation routine in Lat./Long. and the corresponding closest point in the source matrix. If the user choses to process the entire 1 by 2 degree grid at once (as is most convenient) these values are easily determined [the first closest point would be (1,1)]. See the program for other notes. NOTE: GRDMATV3/V4A.FOR is the monster program in this process, requiring up to 50 hours of run-time and costing about 900 charge units (1 charge unit = $1.42) if run during prime time. Its storage arrays require about 12 megabytes of virtual memory. Because the VAX has only 10 megabytes total of physical memory page faulting occurs--this slows down the run. . 4.) MESHING DATA MESH2.FOR combines the DEM and GRDCELL data, each stored on separate tapes, onto one tape that stores the data profiles in groups of three: elevation, land code, and town code along north-to-south profiles. As with the original DEM data, each profile contains 1201 points. Two headers begin each block: elevation profiles are headed by the starting Long./Lat., gridcell profiles by profile number and data-type (1 = land code; 2 = census code). At 12 bytes per field the blocksize is 14436 bytes. At this stage the number of profiles in the data set is not limited except by the tape storage limit. Two degrees data (2400 profiles, covering a 1 by 2 degree rectangle) can easily be stored on a 1200 ft. 9-track tape if written at 6250 bytes per inch (BPI). At 1600 BPI only 900 profiles or so will fit. B-4 5.) THE MASTER SET At this point a master data set exists, from which the hypsometry of all the towns fully contained in it can be computed. HYPSO3.FOR collects all the data for one town and performs a frequency count of elevation points. Areal percent and cumulative areal percent are calculated for all the elevations encountered above three meters. These data are written as a table into a file. A second table also is produced displaying corrected data that are "unclustered" by the Giese method (see below). HYPSO4.FOR is a second version that uses two different correction routines, writing out three tables. The user then chooses the most desirable of the two and edits out the other. At this stage the land-type codes are used to cull the data set. Data points not counted include those existing on beaches, in wetlands, or in water bodies. The resulting data set represents the 'upland' area of the town selected. HYPSO3/4 allows the user to specify a search bracket, defined by profile numbers, to reduce run time. If data for a single town are found in several different master set files, several output files of HYPSO3 may be combined using CURVADD.FOR. CURVADD only adds the corrected data tables. If running HYPS04, one of the corrected tables must be eliminated before inputting to CURVADD or HYPLOT2. 6.) UNCLUSTERING As mentioned in the text of this report, when the cumulative distributions of elevation data are compiled for a town, it is evident that the USGS data are biased toward maxima in the vicinity of 3, 15, 30, 45 and higher multiples of 15 m. HYPSO3/4 smooth the data using a linear redistribution technique which preserves the total number of data points within each "cluster". HYPSO3 sets equal the number of data points at 3, 4 and 5 meters, and redistributes the excess in a linear fashion between 6 and 14 meters. Next, the number of points at 15, 16 and 17 meters is set equal, and the excess is distributed linearly between 18 and 29 meters. This process is then continued for each set of 15 one-meter elevation categories. HYPSO4 differs only in the respect that the first cluster ends at 13 meters (instead of 14), but the second and subsequent clusters end at the same values as in HYPS03. 7.) PLOTTING HYPLOT2.FOR reads the output of CURVADD.FOR or HYPSO3.FOR and creates a plot file using DISSPLA routines. B-5 C. PART TWO: HYPSOMETRY OF THREE HARBORS-- CONTOURING, COASTAL FLOODING, AND GROUNDWATER EFFECTS NOTE: The full procedure for this operation is described only for Hyannis. Details that differ for the other harbors are outlined in following sections. HYANNIS 1.) DATA GENERATION Elevation Data: For this harbor a rectangle 4000 by 5000 meters was delineated, its southwest comer at UTM (391000,4609000). Within this area all contours were digitized, with different prefixes used to indicate the Z-coordinate or elevation values. Pond boundaries were input as separate contours. The shoreline was assigned an elevation of two feet relative to the NGVD of 1929 (this figure represents half the current tidal range plus six inches of sea level rise since 1929). Offshore contours were digitized, and contours valued at -3 and -4 ft. were added just offshore to help constrain the shoreline position. Approximately 11300 data points were recorded. Scaling: A scale of 6.34969 meters per inch for 1:25,000 quadrangle maps yields output having a *10 scaling (units of decimeters). The origin must be entered as (0,0) so that the digitizer's five-digit integer output buffers are not overflowed. This offset is added back during reformatting in MINFORM.FOR and MINOFF.FOR, such that coordinate values are in the Universal Transverse Mercator System (UTM). NOTE: A first attempt to generate this data set used a lower data density and thus produced only 6300 points (HYI*.DIG and .DAT). -30 ft. was used as the offshore contour depth, but was found to cause modelling problems onshore. Modelling the crucial low elevation areas (i.e., 1-10 ft.) presents a problem stemming from poor offshore (bathymetric) data. If only those offshore contours plotted on the topographic map are used to constrain the surface, shoals may be created just offshore and the shoreline is positioned poorly due to the extremely gentle slope in this area. Using artificially deep data points just offshore defines the position of the shoreline quite well, but will arch the onshore surface just inside the constraining shoreline data points. The compromise settled on is represented by the UPL4.DIG & DAT and OFF5.DIG & DAT combined into the HY5.DAT data file, and uses points of moderate depth to position the shoreline but not deform the onshore model to a great degree. B-6 2.) FORMATTING DIGITIZER OUTPUT FOR MINCURV: MINFORM.FOR and MINOFF.FOR are the programs used to put the digitizer output into X, Y, Z format for input to MINCURV.FOR.The digitizer will attach prefixes to its data output, but is limited to 14 different strings (AD-DD, OD-9D). To distinguish between all the different contours, pond boundaries, shoreline and shoreline structure vectors, as well as offshore contours, digitized data were processed in two batches where each prefix was translated into an appropriate elevation or depth. After formatting these two batches are merged into one file for gridding. Documentation contained in MINFORM.FOR and MINOFF.FOR explains how this was done for Hyannis. Other versions of these programs were written to accomodate other harbors. Perhaps a generic version will become appropriate that allows interactive assignment of certain Z-coordinate values to digitizer prefixes if many such maps are to be generated in the future. 3.) GRIDDING: PUBLIC: MINCURV was used to generate an evenly spaced grid of elevation points. To retain full resolution within the single-precision storage arrays used by MINCURV, the first two digits of the northing and first digit of the easting value are not read in. This fix leaves the coordinates in a form that is still compatible with the USGS's UTM notations (i.e., our coordinates are what appear in upper case digits on the quadrangle maps). The nformation Processing Center's (IPC) documentation of MINCURV is good. See our sample run as well. A FEW HINTS: -Remember to read data as F_.1 to account for the *10 scaling. -Oversize the output grid to avoid loosing any data. -When entering Min and Max values for X and Y, drop the appropriate leading digits. MINCURV'S method: MINCURV performs a minimum curvature surface fit using the data provided. Therefore, slope breaks may affect the modelling of adjacent portions of the surface, especially in areas of low data density. This feature becomes troublesome when it becomes necessary to constrain the shoreline position more tightly than is done by the USGS 10-foot contours. To resolve the shoreline more closely, intuitively derived elevation data must be added immediately above and below the shoreline. A relatively steep nearshore slope is required to achieve the proper constraints, resulting in a slope break at the shoreline that can lead to an B-7 unrealistic arching of the onshore surface. This undesirable effect is mitigated by minimizing the slope break and further constraining the onshore surface with onshore data that 'hold down the arch'. FILES IN [.DIGDAT] - '*.DIG' Files are digitizer output -'*.DAT' Files are reformatted for input to MINCURV -'*.GRD' Files are output of MINCURV -'*.VEC' Digitizer output for vector plotting. Only the shore vector doubles as a contour. NOTE: '.GRD' files become '.DAT' when transferred to [.HYP] because UNIRAS needs to see the '.DAT' suffix. 4.) PLOT PREVIEWING WITH THE RASTEC: The Raster Technologies Monitor is an extremely convenient way to examine a data set and perform some quick modelling of sea level rise effects. 1. 'RASTEC:RASTECDEF' enables interactive use of Rastec. It currently is executed by the PES login file. 2. RASTEC is available only on the RED VAX. PES is accessible from RED using the same login name and password. 3. The RASTEC is 512 by 512 pixels, so that plot resolution is limited by data density before it is limited by the hardware (unless, of course, MINCURV output grids exceed this size). 4. HYPRT.FOR is Roger Goldsmith's program to set up the plot image. 5. RASTEC is a pixel-by-pixel representation of the input grid, using 255 different intensity levels of three different colors to show elevation values. It does not contour; therefore edges will show some noise with an amplitude similar to the grid interval used by MINCURV (for Hyannis= 20 m.) 'HYPRT.EXE' asks for a minimum Z value and a Z increment. For example: if -16 is entered for Z-minimum. and 1 is given as the Z increment, -16.0 through -16.9 values are assigned intensity 1. Z-values of 0 through .9 are assigned intensity 17. This decimal truncation, if not accounted for, can produce some unwanted results. If the Z-increment is lowered to .1, only values of -16.0 will be intensity 1, but the Rastec will run out of intensity values at 25.5 feet above the minimum. B-8 6. An assortment of 'LUTRMP' (look-up table) commands allows the user to specify the intensity ranges displayed for different colors over different ranges of original intensities. This system is enabled after running HYPRT.EXE by entering 'RTLOCAL'. A '!' prompt is then displayed and these commands can be entered. 'CSAV filename' saves all subsequently entered commands. 'CINPUT filename' executes this command string. 'QUIT' terminates the 'RTLOCAL' mode. Reference the RASTEC User's Manual and abbreviated pamphlet for details regarding these and other commands. 5.) UNIRAS PLOTTING: HYPUC.FOR is R. Goldsmith's program to plot harbor maps. It needs to see 5 files, all having the same name but different extensions: *.DAT-- MINCURV output (copy from [.DIGDAT]*.GRD) *.IND-- Data set size parameters I*LIM-- Class and color definitions (contouring directions) *.TEX-- Text plotting directions (optional) *.POL-- Polygon plotting directions (optional) Roger's program documentation indicates the formats for each of these files, but here we outline a few additional hints for the lay-user and beginner. Data set size parameters: Look at format carefully. Maximum coordinates are included both as Latitude, then Longitude as well as X, then Y. Limits: UNIRAS default colors are listed in the RASPAK Manual as the 'CMY' dithering technique menu. Defining one's own colors is not hard and produces better results, once some familiarity with the RGB system is achieved. *.LIM must be assigned to 'LIMITS' before each run. Note: The contouring limits are what we use to represent flood-levels for various sea level rise scenarios. This way the inundated area corresponding to a particular vertical rise in sea level is denoted by the colors associated with the contour intervals between present sea level and the predicted rise. Text plotting: Again, follow format closely. Assign *.TEX to'TEXT'. Vector plotting: Vector plotting in the UNIRAS system is controlled by a '.POL' file that contains all the information necessary to have UNIRAS plot a set of vectors, polygons, and fill any polygons so designated. Vectors must be plotted in segments of less than 1000 points. Vectors and polygons appearing later in the file will be plotted over the earlier ones, obscuring them where overlap occurs. Assign *.POL' to 'POLYS'. B-9 Polygon plotting independent of the coastal contouring scheme was used to represent the enlargement of inland water bodies due to the rise in groundwater table. It was assumed that the groundwater table rise is equal to sea level rise. 'VECTOR.FOR' is a program written to create a '.POL' file interactively. It asks the user for certain data and reads in the plot data from a digitizer output file. Creating the plot: To run HYPUC.FOR: Assign TT T41XX HYPUC.FOR makes a UNIRAST.DAT file To send plot to TK4695: 1) Assign the desired version of UNIRAST.DAT file to the most recent version number 2) Type 'ASSIGN TT T4695' 3) Type 'DUNIRAS TK4695' To send plot to RASTEC: 1) Assign TT 41XX 2) Type 'DUNIRAS RASTEC/SC=SC' WESTPORT The Westport map area was established in a manner similar to the Hyannis area. Its origin is at UTM (324000,4696000) and is 4000 meters on a side. Only one inland water body is contained in the Westport map area, at one foot above mean high water. Flood level contours generated for the sea surface were considered legitimate for this coastal pond as well. Several versions of this data base exist; the latest is GL3.dat. At a scale of 1:25,000, there are 60.96012 meters per inch. Digitizer (*10) scaling is 6.0967012. GLOUCESTER Gloucester presented a radically different geology and land surface for flood modelling. Again the grid was set up along UTM lines with the origin at UTM (361500,4716500), extending 4000 meters east and north. Changes in the groundwater table were considered negligible here because of the relatively impermeable bedrock that contains it. Gloucester's steep and crenulated nearshore and its several extensive marshes made this harbor the most difficult to model. Four revisions were necessary. The current data base is GL4.dat. At a scale of 1:25,000, there are 60.96012 meters per inch. Digitizer (* 10) scaling is 6.0967012. B-1 0