[Federal Register Volume 62, Number 83 (Wednesday, April 30, 1997)]
[Rules and Regulations]
[Pages 23377-23392]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 97-11194]
[[Page 23377]]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
50 CFR Part 17
RIN 1018-AC22
Endangered and Threatened Wildlife and Plants; Final Rule To List
the Barton Springs Salamander as Endangered
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Final rule.
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SUMMARY: The Fish and Wildlife Service (Service) determines the Barton
Springs salamander (Eurycea sosorum) to be an endangered species
pursuant to the Endangered Species Act of 1973, as amended (Act). The
Barton Springs salamander is known only from Barton Springs in Zilker
Park, Austin, Travis County, Texas. The primary threats to this species
are degradation of the quality and quantity of water that feeds Barton
Springs due to urban expansion over the Barton Springs watershed. Also
of concern is disturbance to the salamander's surface habitat in the
pools where it occurs. This action implements Federal protection
provided by the Act for the Barton Springs salamander.
EFFECTIVE DATE: May 30, 1997.
ADDRESSES: The complete file for this rule is available for inspection,
by appointment, during normal business hours at the Ecological Services
Field Office, U.S. Fish and Wildlife Service, 10711 Burnet Road, Suite
200, Austin, Texas 78758.
FOR FURTHER INFORMATION CONTACT: Lisa O'Donnell, Fish and Wildlife
Biologist (see ADDRESSES section) (telephone: 512/490-0057; facsimile
(512/490-0974)).
SUPPLEMENTARY INFORMATION:
Background
The Service determines the Barton Springs salamander (Eurycea
sosorum) to be an endangered species, under the authority of the
Endangered Species Act (Act) (16 U.S.C. 1531 et seq.). The Barton
Springs salamander is entirely aquatic and neotenic (meaning it does
not metamorphose into a terrestrial form and retains its bright red
external gills throughout life) and depends on a constant supply of
clean, flowing water from Barton Springs. Adults attain an average
length of 6.35 centimeters (cm) (2.5 inches (in)). This species is
slender, with slightly elongate limbs and reduced eyes. Dorsal
coloration varies from pale purplish-brown or gray to yellowish-cream.
Irregular spacing of dorsal pigments and pigment gaps results in a
mottled, ``salt and pepper'' pattern (Sweet 1978, Chippindale et al.
1993a).
The Barton Springs salamander was first collected from Barton
Springs Pool in 1946 by Bryce Brown and Alvin Flury (Chippindale et al.
1993a,b). Although he did not publish a formal description, Dr. Samuel
Sweet (University of California at Santa Barbara) was the first to
recognize the Barton Springs salamander as distinct from other central
Texas Eurycea salamanders based on its restricted distribution and
unique morphological and skeletal characteristics (such as its reduced
eyes, elongate limbs, dorsal coloration, and reduced number of
presacral vertebrae) (Sweet 1978, 1984). Based on Sweet's work and
genetic studies conducted by Chippindale et al. (1990, 1992, 1993b),
the Barton Springs salamander was formally described in June 1993
(Chippindale et al. 1993a). An adult male (based on external
examination only) collected from Barton Springs Pool in November 1992
was selected to be the holotype (Chippindale et al. 1993a).
The water that discharges at Barton Springs originates from the
Barton Springs segment of the Edwards aquifer (hereafter referred to as
the ``Barton Springs segment''). Barton Springs is the fourth largest
spring in Texas, exceeded only by Comal, San Marcos, and San Felipe
springs (Brune 1981). The Barton Springs salamander is found near three
of four hydrologically connected spring outlets that collectively make
up Barton Springs. These three spring outlets are known as Parthenia
(=Main), Eliza (=Concession, =Elk's), and Sunken Garden (=Old Mill,
=Walsh) springs, and they occur in Zilker Park, which is owned and
operated by the City of Austin. No salamanders have been found at the
fourth spring outlet, which is in Barton Creek immediately above Barton
Springs Pool (Chippindale et al. 1993a,b; Sweet, pers. comm., 1993;
Robert Hansen, City of Austin, in litt., 1995a; William Russell, Texas
Speleological Survey, in litt. 1995). The area around the main spring
outlet (Parthenia Springs) was impounded in the late 1920's to create
Barton Springs Pool. Flows from Eliza and Sunken Garden springs are
also retained by concrete structures, forming small pools located on
either side of Barton Springs Pool. The salamander has been observed at
depths of about 0.1 to 5 meters (m) (0.3 to 16 feet (ft)) of water
under gravel and small rocks, submerged leaves, and algae; among
aquatic vegetation; and buried in organic debris. It is generally not
found on exposed limestone surfaces or in silted areas (Sweet 1978; Dr.
Charles Sexton, City of Austin, in litt., 1992; Chippindale et al.
1993a,b; Jim Collett, Robert Hansen, and Mateo Scoggins, City of
Austin, pers. comms., 1994-1995; Lisa O'Donnell, U.S. Fish and Wildlife
Service (USFWS), pers. obs., 1996).
``Dozens or hundreds'' of individuals were estimated to occur among
sunken leaves in Eliza Pool during the 1970's (Chippindale et al.
1993a,b), while fewer than 15, and occasionally no individuals, were
observed during surveys conducted in Eliza Pool between 1987 and 1992
(Chippindale et al. 1993a,b). No salamanders were observed at this
location between December 1993 and May 1995 (Paul Chippindale,
University of Texas at Arlington, Collett, Hansen, and Scoggins; pers.
comms., 1994-1995; Hansen in litt. 1995b). Numbers ranged from 0 to 28
between June 1995 and July 1996, and dead salamanders have been found
(O'Donnell, unpubl. data, 1995-1996).
The Barton Springs salamander was reportedly abundant among the
aquatic vegetation in the deep end of Barton Springs Pool when it was
collected in 1946 (Hillis and Chippindale 1992; Chippindale et al.
1993a,b). Between 1989 and 1991, Sexton (in litt., 1992) reported
finding salamanders under rock rubble immediately adjacent to the main
spring outflows on ``about one out of four [snorkeling] dives.'' On
July 28, 1992, at least 50 salamanders (David Hillis, University of
Texas at Austin, pers. comm., 1993) were found over an area of roughly
400 square (sq) m (4,300 sq ft) near the spring outflows in Barton
Springs Pool, about 3 to 5 m (10 to 15 ft) below the water (Chippindale
et al. 1993a,b). Following reports of a fish kill on September 28,
1992, attributed to the improper application of chlorine to clean
Barton Springs Pool, only 10 to 11 salamanders were observed and could
only be found in an area of about 5 sq m (54 sq ft) in the immediate
vicinity of the Parthenia Spring outflows (Chippindale et al. 1993a,b).
At least 80 individuals were observed during the first comprehensive
survey effort conducted in Barton Springs Pool on November 16, 1992,
and about 150 individuals were seen on November 24, 1992 (Chippindale
et al. 1993a,b). A comprehensive survey conducted immediately following
an October 1994 flood event reported a total of 16 salamanders, and a
total of 10 salamanders was counted in March 1995 (Hansen, in litt.
1995c).
The City of Austin initiated monthly transect surveys in June 1993
to provide
[[Page 23378]]
more consistent data concerning the range and size of the Barton
Springs salamander population in Barton Springs Pool. Survey counts
ranged from 1 to 27 individuals (mean = 13) between July 1993 and March
1995. The highest survey counts (27 individuals) were reported in
November 1993 and May 1994. The lowest counts (ranging from 1 to 6
individuals) occurred during a five-month period following the October
1994 flood event (Hansen, in litt. 1995c). Survey counts between April
1995 and April 1996 ranged from 3 to 45 salamanders (City of Austin,
unpubl. data).
The salamander was first observed at Sunken Garden Springs on
January 12, 1993 (Chippindale et al. 1993b). Less than 20 individuals
have been reported on any given visit to that outlet (Chippindale
1993b; Hansen, pers. comm., 1995). Because it is part of the Barton
Springs complex and is hydrologically connected to Parthenia Springs,
biologists had speculated that the salamander occurred at Sunken Garden
Springs. However, no salamanders were observed during previous surveys
conducted at this location between 1987 and 1992. Low water levels and
the presence of large rocks and sediment make searching for salamanders
difficult at Sunken Garden Springs (Chippindale et al. 1993b;
O'Donnell, pers. obs., 1995).
No evidence exists that the species' range extends beyond the
immediate vicinity of Barton Springs. Despite survey efforts and
searches at other spring outlets, caves, and uncased wells in the
Barton Springs segment, no other locations of the Barton Springs
salamander have been found (Chippindale et al. 1993a,b; Russell, in
litt. 1995; Russell 1996; Hillis; Andy Price, Texas Parks and Wildlife
Department; Sweet; pers. comms., 1993; Hansen, in litt. 1995a). No
other species of Eurycea is known to occur in this portion of the
aquifer. Although the extent to which the Barton Springs salamander
occurs in the aquifer is unknown, it is likely concentrated near the
spring openings where food supplies are abundant, water chemistry and
temperatures are relatively constant, and where the salamander has
immediate access to both surface and subsurface habitats. Barton
Springs is also the main discharge point for the entire Barton Springs
segment, and is one of the few perennial springs in the area.
The Barton Springs salamander's diet is believed to consist almost
entirely of amphipods (Hyallela azteca) and other small invertebrates
(James Reddell, Texas Memorial Museum, University of Texas at Austin,
pers. comm., 1993; Hillis and Chippindale 1992; Chippindale et al.
1993a,b). Primary predators of the Barton Springs salamander are
believed to be fish and crayfish (Chippindale et al. 1993a,b; Collett,
Hansen, and Scoggins, pers. comms., 1995). Observations of larvae and
females with eggs indicate breeding occurs year-round (Chippindale,
pers. comm., 1993; Collett, Hansen, and Scoggins, pers. comms., 1994-
1995). The Barton Springs salamander's eggs are white (Lynn Ables and
Streett Coale, Dallas Aquarium; Jim Dwyer, Midwest Science Center;
pers. comms., 1996) and have never been observed in the wild
(Chippindale, Hillis, and Price, pers. comms. 1993; Collett, Hansen,
and Scoggins, pers. comms., 1994-1995; O'Donnell, pers. obs., 1995-
1996).
The Barton Springs segment covers roughly 400 sq kilometers (km)
(155 sq miles (mi)) from southern Travis County to northern Hays
County, Texas, and has a storage capacity of over 37,000 hectare-meters
(300,000 acre-feet) (Slade et al. 1985, 1986). The watersheds of the
six creeks upstream (west) of the recharge zone span about 684 sq km
(264 sq mi). This area is referred to as the contributing zone and
includes portions of Travis, Hays, and Blanco counties. The recharge
and contributing zones (hereafter referred to collectively as the
''Barton Springs watershed'') make up the total area that provides
water to the aquifer, which equals about 917 sq km (354 sq mi). A
detailed description of the Barton Springs segment of the Edwards
aquifer can be found in the Service's February 17, 1994, proposed rule
(59 FR 7968). Porous limestone, karst aquifers, such as the Barton
springs segment may transport pollutants rapidly once such materials
enter the creeks or other recharge features (EPA 1990, TWC 1989, Slade
et al.1986, Ford and Williams 1994, Notenboom et al. 1994)
Because of the characteristics of karst aquifers, Barton Springs is
believed to be heavily influenced by the quality and quantity of
runoff, particularly in the recharge zone (City of Austin 1991; Slade
et al. 1986). Thus, increasing urban development over the area
supplying recharge waters to the Barton Springs segment can threaten
water quality within the aquifer. The Texas Water Commission (now known
as the Texas Natural Resource Conservation Commission (TNRCC))
identified the Edwards aquifer as being one of the most sensitive
aquifers in Texas to groundwater pollution (TWC 1989; Hart, in litt.,
1991; TNRCC 1994).
Previous Federal Action
The Barton Springs salamander was a Category 2 candidate species on
the Service's candidate notices of review from December 30, 1982 (47 FR
58454; September 18, 1985: 50 FR 37958; January 6, 1989: 54 FR 554; and
November 21, 1991: 56 FR 58804) until publication of the proposed rule
to list the species as endangered (59 FR 7968; February 17, 1994). Dr.
Mark Kirkpatrick and Ms. Barbara Mahler petitioned the Service to list
the Barton Springs salamander on January 22, 1992, and on December 11,
1992 (57 FR 58779), the Service published a notice in the Federal
Register that the petition presented substantial information that the
requested action may be warranted. A proposed rule to list the Barton
Springs salamander was published in the Federal Register on February
17, 1994 (59 FR 7968). The Service held a public hearing on June 16,
1994, in Austin, Texas (59 FR 27257). On March 10, 1995, the Service
published a notice extending the 1-year deadline for final action on
the proposed rule until August 17, 1995, and reopened the public
comment period (60 FR 13105).
On April 10, 1995, Congress enacted a moratorium prohibiting work
on listing actions (Public Law 104-6) and eliminated funding for the
Service to conduct final listing actions. On November 27, 1995, in
response to a lawsuit from the Save Our Springs Legal Defense Fund
(Save Our Springs Legal Defense Fund, Inc., et al. v. Bruce Babbitt), a
U.S. District Court invalidated the Service's March 10, 1995, notice of
extension and ruled that the Service had to make a final determination
on whether or not to list the Barton Springs salamander within 14 days
of the court order. The court granted a stay pending the Service's
appeal of the order, on the grounds that the moratorium and lack of
funding prohibited the Service from making a final listing
determination. The moratorium was lifted on April 26, 1996, by means of
a Presidential waiver, at which time limited funding for listing
actions was made available through the Omnibus Appropriations Act (Pub.
L. No. 104-134, 100 Stat. 1321, 1996). The Service published guidance
for restarting the listing period on May 16, 1996 (61 FR 24722). Due to
the potential for new information during the lapse between the
reinstatement of the listing program and the close of the last 45-day
comment period (May 17, 1995), the Service reopened the public comment
period on June 24, 1996, for 30 days. That comment period closed July
10, 1996, by U.S. District Court order.
[[Page 23379]]
On September 4, 1996 (61 FR 46608), the Service withdrew the
proposed rule to list the Barton Springs salamander as endangered based
on a conservation agreement signed by the Service and the TNRCC, Texas
Parks and Wildlife Department (TPWD), and Texas Department of
Transportation (TxDOT) on August 13, 1996. The goal of the Barton
Springs Salamander Conservation Agreement and Strategy (Agreement) is
to continue existing and initiate new management actions to protect the
Barton Springs ecosystem and its watershed. The Agreement is
administered by the Barton Springs Salamander Conservation Team
(BSSCT), which includes representatives from each of the four signatory
agencies. In deciding to withdraw the proposed listing rule, the
Service found that the Agreement, by protecting water quality at Barton
Springs and in the Barton Springs segment of the Edwards aquifer and by
conserving water quantity, reduces the threats to the species to the
point where listing is no longer warranted.
On March 25, 1997, the U.S. District Court for the Western District
of Texas found the Service's withdrawal invalid and ordered the Service
to make a listing determination within 30 days. The court ordered the
Service to ignore the Agreement in making the new decision. On April 8,
1997, the Service requested the court to delay the due date for the new
listing decision until July 23, 1997, so that the Service could reopen
the comment period and consider information developed since July 10,
1996, when the comment period on the proposed listing closed. The court
denied this request on April 15, 1997. The Service is therefore not
able to consider the following information in making a final listing
determination: (1) The Agreement and the BSSCT's efforts to implement
it, including public and technical input given as part of the BSSCT's
March 1, 1997 public workshop; (2) updated salamander survey results;
(3) the City of Austin's revised pool maintenance procedures designed
to reduce salamander mortality; (4) the discovery of a new salamander
location upstream from the Barton Springs Pool; (5) two additional
ovipositioning events at the Dallas Aquarium; (6) reinstatement of the
Save Our Springs (SOS) ordinance; (7) the Barton Creek Watershed
Protection Initiative with private landowners and the Nature
Conservancy of Texas; and (8) and adoption of TNRCC's chapters 313 and
216 of the Texas Administrative Code (see discussion under Factor D
below).
Summary of Comments and Recommendations
In the February 17, 1994, proposed rule (59 FR 7968) and associated
Federal Register notices, including notification of a public hearing
(59 FR 27257; May 26, 1994) and each of the five comment periods
(February 17 to April 18, 1994 (59 FR 7968); May 26 to July 1, 1994 (59
FR 27257; May 26, 1994); July 8 to July 29, 1994 (59 FR 35089; July 8,
1994); March 10 to May 17, 1995 (60 FR 13105; March 10, 1995); and June
24 to July 10, 1996 (61 FR 32413; June 24, 1996)), all interested
parties were requested to submit factual reports or information to be
considered in making a final listing determination. Appropriate Federal
and State agencies, local governments, scientific organizations, and
other interested parties were contacted and asked to comment. Legal
notices of the public hearing, which invited general public comment
were published in the Dripping Springs Century News and Austin-American
Statesman on June 8, 1994, in the Drippings Springs Dispatch on June 9,
1994, and in the Austin Chronicle on June 10, 1994. The Service
received 657 written and oral comments, 8 videotapes, 5 petitions, and
2 resolutions from individuals and agencies. Of the 657 comments, 524
supported the proposed action, 123 opposed it, and 10 stated neither
support nor opposition. Four petitions totaling over 1,800 signatures
and one resolution from the City of Austin supported listing, and one
petition containing 29 signatures and one resolution from the City of
Dripping Springs opposed the listing.
A public hearing was held in two sessions on June 16, 1994, at the
Lyndon Baines Johnson Auditorium at the University of Texas at Austin.
Over 160 people attended the public hearing, and 74 provided oral
testimony.
The Service solicited formal scientific peer review of the proposal
from six individuals during the March 10 to May 17, 1995, comment
period and received comments from three reviewers. The major comments
from these peer reviewers are: the Barton Springs salamander is a
distinct species restricted to Barton Springs; the salamander appears
to be primarily a surface-dwelling species that retreats underground
during unfavorable conditions (such as drought) and to lay eggs; the
salamander is vulnerable to declining water quality and quantity and
other forms of habitat modification; regulations are inadequate to
protect the Barton Springs salamander; the Service should present more
data that show increasing levels of pollutants in the groundwater; the
Service should provide further explanation as to why the Barton Springs
salamander is restricted to Barton Springs; and increased nutrient
levels should not affect dissolved oxygen concentrations in the
aquifer. The peer reviewers' comments are reflected in this final rule.
Written and oral comments are incorporated into this final rule
where appropriate. Comments not incorporated are addressed in the
following summary. Comments of a similar nature or point are grouped
and summarized. Where differing viewpoints on an issue were expressed,
the Service briefly summarizes the general issue.
1. Comment: Several commenters questioned whether information
regarding threats to the Barton Springs salamander is adequate to
support a listing decision. Some commenters stated that threats to the
salamander are greater now than ever before.
Service Response: Section 4(a)(1) of the Act states that species
shall be listed as threatened or endangered provided that the continued
existence of the species is threatened by one or more of the five
factors discussed below in the ``Summary of Factors Affecting the
Species'' section of this rule. Under section 4(b)(1), the Service must
make its listing decisions based on the best scientific and commercial
data available. The Service has met these requirements in this listing
decision.
Over 50 percent of the water used by Texans comes from groundwater.
The Barton Springs watershed provides the sole source of drinking water
for more than 35,000 people living over the aquifer and contributes a
significant supply of water to the Colorado River, which is the primary
source of drinking water for the City of Austin. In addition to
providing a reliable supply of safe drinking water that requires little
or no treatment, many people depend on the Barton Springs watershed for
other needs, including agriculture and recreational activities.
Amphibians are known to be very sensitive to environmental
contaminants (see Factor E below). Because the Barton Springs
salamander lives at the main discharge point for the aquifer and is
continuously exposed to the waters emanating from it, it is a primary
indicator of the health of this natural resource. As an important
indicator species, the Barton Springs salamander serves as an early
warning sign of deteriorating water quality and quantity in the Barton
Springs watershed, which affects the health and
[[Page 23380]]
well-being of the human population that depends on this resource.
2. Comment: The Service received comments questioning the
sensitivity of the Barton Springs salamander to changes in water
quality and quantity, and asserting that since the salamander has
survived past impacts, it appears to be hardy and resilient and able to
withstand future impacts.
Service Response: Although the Barton Springs salamander has
survived past impacts, only 4 to 6 percent of the Barton Springs
watershed is currently developed, and development is expected to
continue. Furthermore, although the species as a whole has persisted to
date, survey information indicates that individual salamanders have not
survived certain impacts, and the species and its prey base are
vulnerable to changes in water quality and quantity (see Factors A and
E below). As discussed in Factor E, the difficulty in maintaining and
propagating the Barton Springs salamander in captivity provides further
evidence that this species is sensitive to environmental change.
Toxicity data for the salamander's primary food source, Hyallela
azteca, demonstrate the sensitivity of that amphipod to contaminants.
3. Comment: Several people commented on the adequacy of the
existing rules and regulations in protecting water quality and quantity
in the Barton Springs watershed. One commenter specifically mentioned
that, because only two oil pipeline spills have been recorded (see
Factor A), regulations are apparently adequate to protect water
quality.
Service Response: The Act states that species shall be listed based
on one or more of the five factors discussed in this final rule. The
Service's analysis of the inadequacy of existing regulatory mechanisms
(Factor D) demonstrates that additional measures are needed to protect
the Barton Springs salamander from extinction. Although certain rules
and regulations provide some water quality and quantity benefits, they
do not alleviate all of the identified threats to the Barton Springs
salamander.
4. Comment: Several inquiries were made regarding possible effects
of listing the Barton Springs salamander on land use in the Barton
Springs watershed and whether listing would infringe on private
property rights. Other comments discussed possible economic impacts and
benefits from listing.
Service Response: While economic effects, private property rights,
and related concerns, cannot be considered in listing decisions, such
factors are considered in recovering listed species. By Federal
Register notice on July 1, 1994 (59 FR 34272), the Secretaries of
Interior and Commerce set forth an interagency policy to minimize
social and economic impacts consistent with timely recovery of listed
species. Thus, it is the Service's desire that any recovery actions
associated with the Barton Springs salamander minimize adverse social
and economic impacts to the extent practicable.
5. Comment: The Service received several comments on the status of
the Barton Springs salamander's population size, stating that this
information should be considered in making a listing determination.
Service Response: Data from monthly surveys of the Barton Springs
salamander are presented in the Background section and Factor A of this
final rule. These survey data further support the need for listing.
Although it may be an important listing consideration, the absolute
population size does not need to be declining to warrant listing under
the Act.
6. Comment: The Service received several comments regarding whether
the Barton Springs salamander is restricted to Barton Springs.
Service Response: Survey information of other springs, caves, and
wells in the Barton Springs segment provided since publication of the
proposed rule further substantiate that the Barton Springs salamander's
range is limited to the immediate vicinity of Barton Springs (see
Background). Because Sunken Garden Springs is part of the Barton
Springs complex and scientists assumed that the Barton Springs
salamander occurred there, the presence of salamanders at this spring
outlet does not indicate that the salamander's range has expanded, as
some commenters asserted.
7. Comment: Many people questioned whether recreational use of
Barton Springs Pool is likely to impact the Barton Springs salamander.
Service Response: The Service recognizes that swimming is a
compatible activity with conservation of the salamander. The Service
has provided additional discussion on recreation related issues in
Factor E (``Other natural or manmade factors affecting its continued
existence'') of this final rule. The Service acknowledges in both the
proposed and final rules that certain pool maintenance practices may
impact the Barton Springs salamander, and that the City of Austin is
continuing to seek solutions that benefit both the recreational aspect
of Barton Springs Pool and the Barton Springs salamander (see Factor
A).
8. Comment: The Service received several comments regarding whether
critical habitat should be designated for the Barton Springs
salamander.
Service Response: Critical habitat has not been proposed for the
Barton Springs salamander (see Critical Habitat section below). The Act
requires that critical habitat be designated for a species at the time
it is listed unless designation is not prudent or not determinable.
Listing regulations at 50 CFR 424.12(a)(1) provide that critical
habitat is not prudent if no benefit to the species is derived from its
designation. Designation of critical habitat benefits a listed species
only when adverse modification or destruction of critical habitat could
occur without the survival and recovery of the species also being
jeopardized. Because the Barton Springs salamander is restricted to one
area that discharges water from the entire Barton Springs watershed,
any action that would result in adverse modification or destruction of
the salamander's critical habitat would also jeopardize its continued
survival and recovery. Designating critical habitat would therefore not
provide a benefit to the species beyond the benefits already provided
by listing and subsequent evaluation of activities under the jeopardy
standard of section 7 of the Act. Because jeopardy to the species and
adverse modification of its critical habitat are indistinguishable, the
Service has determined that designation of critical habitat for the
Barton Springs salamander is not prudent.
9. Comment: A few commenters questioned whether the Barton Springs
salamander represents a distinct species.
Service Response: The Barton Springs salamander was first
recognized as a distinct species in the 1970's (see Background). A
formal description of the salamander was peer-reviewed and published in
June 1993 (Chippindale et al. 1993a). Although the Barton Springs
salamander may bear some morphological resemblance to other Eurycea
salamander species, differences in its morphology, its isolation from
other Eurycea populations, and genetic research provide sufficient
evidence to support its designation as a distinct species.
10. Comment: The Service received comments questioning whether a
relationship exists between increasing urbanization and declining water
quality and quantity.
Service Response: A discussion of the relationship between
increasing urbanization and declining water quality and quantity is
presented in Factor A of this final rule.
[[Page 23381]]
11. Comment: Some commenters questioned whether reduced aquifer
levels and encroachment of the bad water line constitute threats to the
Barton Springs salamander.
Service Response: A discussion of this issue is presented in Factor
A. Under the 1996 pumping and drought regime, springflows at Barton
Springs reached historically low levels, and both Eliza Pool and Sunken
Garden Springs drained completely dry during drawdown of Barton Springs
Pool. Barton Springs is located near the bad water line, and
encroachment of bad water to the springs has occurred historically
under low flow conditions. During periods of low flows, Sunken Garden
Springs measures high levels of total dissolved solids, indicating bad
water encroachment.
Factor A also presents information on the increasing number of new
permitted wells in the Barton Springs segment and a discussion of
groundwater pumpage. A substantial increase in groundwater withdrawals
(compounded by drought) will increase the frequency, severity, and/or
duration of low aquifer levels and springflows and the potential for
movement of the bad water line toward Barton Springs. Increased pumpage
may also increase leakage from the lower Trinity aquifer, which
contains higher levels of total dissolved solids and fluoride than
water in the Barton Springs segment, thus further lowering water
quality.
12. Comment: The Fish and Wildlife Service needs to implement its
new directives from the Department of Interior and Commerce, including
scientific peer review, minimization of social and economic impacts,
greater predictability, the ecosystem approach, and State agency
involvement.
Service Response: The Service has followed its policy directives in
preparing this final rule. During the reopening of the public comment
period following the notice to extend the final listing decision (60 FR
13105; March 10, 1995), the Service formally solicited peer review from
six independent specialists to evaluate the information presented in
the proposed rule. The beginning of this section (``Summary of Comments
and Recommendations'') summarizes the opinions of the three individuals
who provided peer review. Informal peer review was also solicited
during the public hearing and each public comment period, during which
the Service received over 650 letters of comment. The Service solicited
information and expertise from Federal, State, and local agencies,
including the U.S. Geological Survey, Texas Parks and Wildlife
Department, Texas Natural Resource Conservation Commission, Barton
Springs/Edwards Aquifer Conservation District, and the City of Austin
in preparing the proposed and final rules, and provided written
notifications to these agencies of the 90-day finding and proposed
rule.
The Available Conservation Measures section of this final rule
identifies specific activities that will not be affected by section 9
of the Act regarding ``take'' of the Barton Springs salamander, and
provides guidance and recommendations for avoiding impacts to the
salamander. The recovery plan will be drafted to minimize social and
economic impacts while ensuring the long-term survival and recovery of
the Barton Springs salamander. Protecting the ecosystem upon which the
salamander and people depend will be an important component in recovery
planning.
13. Comment: The Service refuses to acknowledge the benefits of
existing regulations. The Service's unwillingness to enforce its own
limited and inadequate requirements further contributes to the
endangered status of the Barton Springs salamander.
Service Response: As stated in the proposed rule, the Service
acknowledges that the existing rules and regulations provide some
benefits to water quality and quantity. However, the purpose of Factor
D is to evaluate the inadequacies of existing regulatory mechanisms.
The Service hopes that this evaluation will assist in identifying
measures to strengthen efforts to protect water quality and quantity in
the Barton Springs watershed and to promote the long-term survival of
the Barton Springs salamander.
14. Comment: The Service must consider spill response programs
designed to remediate the contamination of groundwater resources by
hazardous substance and hazardous waste releases.
Service Response: The Service is unaware of any concerted,
organized effort among the various Federal, State, and local agencies
to implement a contingency plan for emergency spills in the Barton
Springs watershed. Also, efforts to restore contaminated groundwater to
its original purity may be technologically infeasible and/or cost-
prohibitive (see Factor A). Spill remediation is especially problematic
for catastrophic spills that occur in proximity to Barton Springs or in
areas that are difficult to access. Because remediation is not always
effective or possible, prevention is needed to ensure the protection of
water resources.
15. Comment: Many of the references cited in the proposed rule are
not studies or reports specific to Barton Springs, Austin, or even the
Edwards aquifer, but instead describe general nationwide or statewide
environmental management issues. These are general policy documents,
which do not address the circumstances faced by the Barton Springs
salamander.
Service Response: Most of the reports and documents cited in this
final rule specifically address the effects of urbanization on surface
and groundwater, karst aquifers, the Barton Springs watershed, the
Barton Springs salamander, and/or the salamander's primary food source,
and thus are pertinent to evaluating threats to the Barton Springs
salamander. The information presented in these reports is highly
consistent with respect to the threat of urbanization on water
resources.
16. Comment: The Service cites a 1986 study by Slade et al. that
projected a doubling of water demands from the year 1982 to 2000. Since
we are more than halfway through the 18-year time period, are more
recent data available?
Service Response: The estimated total pumpage in 1982 was 470
hectare-meters (3,800 acre-feet), at which time discharge from the
Barton Springs segment (withdrawal plus springflow) was determined to
be roughly equal to recharge. Slade et al. (1986) predicted that a
substantial increase in groundwater withdrawal (compounded by drought)
would cause a decrease in the quantity of water in the aquifer and
discharge from Barton Springs. The Barton Springs/Edwards Aquifer
Conservation District estimated total pumpage for 1994 at 570 hectare-
meters (4,600 acre-feet). However, as stated in Factor A, the exact
volume of water that is pumped from the aquifer is difficult to
estimate, since meter reports are not required for non-permitted wells.
Furthermore, groundwater pumpage varies considerably from year to year,
influenced primarily by the amount of rainfall. The volume of pumpage
increases and its effects on aquifer levels and springflows become more
pronounced during dry spells, whereas periods of high rainfall can mask
the effects of increased dependence on groundwater supplies.
17. Comment: There appears to be no direct, quantifiable
relationship between water quality in Barton Creek and water quality at
Barton Springs.
Service Response: The Background section and Factor A of this final
rule discuss the hydrologic regime of the Barton Springs watershed. The
surface and groundwaters of the Barton Springs watershed are integrally
related, and all of the six creeks that cross the recharge
[[Page 23382]]
zone of the aquifer affect water quality at Barton Springs. Because of
the karst characteristics of the aquifer and because Barton Springs is
the main discharge point for the entire watershed, pollutants entering
the watershed from any of the recharge sources may eventually reach
Barton Springs. The USGS has clearly demonstrated that water quality in
Barton Creek has the most immediate impact on water quality at Barton
Springs of any recharge source in the Barton Springs watershed because
of its recharge contribution and proximity to Barton Springs. Data show
that contaminants in Barton Creek can enter the aquifer near Barton
Springs and discharge from the springs within hours or days of storm
events.
18. Comment: The waters from the outlying areas of the contributing
zone are not the cause of current degradation and will never
significantly contribute to the degradation of the springs compared to
the existing development around Barton Springs. Many existing land uses
were constructed and operated under less stringent standards.
Retrofitting existing development would result in far more improvement
of water quality than would further restriction of new development.
Service Response: The Service acknowledges that there is a
relationship between current water quality and quantity degradation and
existing development and considers retrofitting of these developments
to be an important factor in protecting Barton Springs. However, water
quality at Barton Springs is also influenced by the quality and
quantity of water throughout the entire watershed (see Background and
Factor A). Although water quality at Barton Springs responds most
rapidly to changes in water quality in Barton Creek, Barton Springs
represents a mixture of all of the recharge waters in the Barton
Springs watershed. High-quality water in the undeveloped portions of
the Barton Springs watershed helps disperse and dilute pollutants from
the urbanized areas. Because of the karst characteristics of the
aquifer, pollution can originate from anywhere within the Barton
Springs watershed, especially pollutants that are relatively stable and
mobile in water. Thus, as urbanization expands across the watershed,
the ability of the aquifer to dilute and disperse increasing pollutant
loads will decrease. While the Service concurs that retrofitting of
existing development near Barton Springs may be important to protect
water quality, measures are also needed to ensure continued protection
of water quality and quantity throughout the remainder of the
watershed. A report prepared for the City of Austin (1995) examines
options for retrofitting developments to improve stormwater quality in
the Barton Springs watershed.
19. Comment: The proposed rule did not discuss other sources of
water contributing to flows from Barton Springs, including the San
Antonio segment of the Edwards aquifer and the Colorado River.
Service Response: Independent studies (Slade et al. 1985, 1986;
Stein 1995) conclude that most of the water discharging from Barton
Springs originates from within the Barton Springs watershed (see
Background section). However, under low flow conditions, the bad water
zone of the San Antonio segment appears to flow northward toward Barton
Springs. Upward leakage from the lower Trinity aquifer may also
infiltrate the Barton Springs segment during low flows. Because these
aquifers are high in total dissolved solids, their contribution affects
the quality of water in the Barton Springs watershed and at Barton
Springs.
The Service is unaware of any reports or data indicating that the
Colorado River contributes water to the Barton Springs watershed.
However, Barton Springs does supply baseflow to the Colorado River,
which may be substantial during dry periods.
20. Comment: The Service must comply with the National
Environmental Policy Act (NEPA) prior to listing the Barton Springs
salamander as endangered. This would require the Service to study the
social and environmental impacts of the proposed listing and prepare
appropriate environmental documentation.
Service Response: The Service has determined that Environmental
Assessments and Environmental Impact Statements, as defined under the
authority of the National Environmental Policy Act of 1969, need not be
prepared in connection with regulations adopted pursuant to section
4(a) of the Endangered Species Act of 1973, as amended. A notice
outlining the Service's reasons for this determination was published in
the Federal Register on October 25, 1983 (48 FR 49244).
21. Comment: The statement that ``Loop 360 provides a major route
for transportation of petroleum and gasoline products to service
stations in the Austin area'' is unsupported by any data or citation of
a study. What is the basis of this statement?
Service Response: This statement was based on the fact that no
designated hazardous materials routes exist for the Austin area, and
thus all major roadways can be considered to be transportation routes
for hazardous materials. Because Loop 360 supports a high volume of
traffic, and many service stations exist in this part of the Austin
area, it is considered to be a major transportation route. The
Service's statement is also supported by the Hazardous Materials Water
Contamination Risk study prepared for the City of Austin (1994).
22. Comment: Both Hays County and Dripping Springs experienced high
rates of growth in the 1980's, yet are still sparsely populated. The
Service's statement in the proposed rule suggests these areas will soon
be overrun with people at intensely urbanized levels, which is an
unrealistic assumption.
Service Response: The Service quoted a study (see Factor A)
conducted by the Capital Area Planning Council. Additional information
on population growth for the northern portion of Hays County is
presented in this final rule.
23. Comment: More of the recharge and contributing zones have been
developed than the Service states in the proposed rule. Based on an
analysis of historical trends in land development for the recharge zone
of the Barton Springs segment, approximately 1,200 hectares (ha) (3,050
acres (ac)) in the recharge zone had been developed in 1979.
Approximately 3,000 ha (7,500 ac) had been developed by 1993, which
represents approximately 13 percent of the entire recharge zone of the
Barton Springs segment.
Service Response: Factor A of the proposed rule states that ``* * *
only about 3 to 4 percent of the recharge and contributing zones is
currently developed,'' which was based on an estimate of impervious
cover provided by the USGS. A report prepared for the City of Austin
(1995) has estimated impervious cover over the Barton Springs watershed
to be 6 percent (see Factor A). Assuming that the commenter's
calculations of development are also equal to the amount of impervious
cover, the commenter's assertion that about 13 percent of the recharge
zone is developed does not appear to be inconsistent with the estimated
3 to 6 percent impervious cover for the entire watershed.
24. Comment: What evidence exists that demonstrates that sediments
entering the pools where the salamander occurs actually settle in the
salamander's habitat?
Service Response: Biologists with the City of Austin have found
that silt and sediments that are hosed from the shallow end into the
deep end of Barton Springs Pool during cleaning reduce the
[[Page 23383]]
amount of available salamander habitat. Increased sediment influxes
following major rain events also reduce habitat availability. Sediments
cover much of the bottom of Eliza Pool and Sunken Garden Springs, and
the Barton Springs salamander is typically found in silt-free areas
near the spring outlets.
25. Comment: A significant number of references cited in the
proposed rule are not peer-reviewed scientific publications and thus
should not be given the same level of credibility as those having a
more rigorous review and approval process.
Service Response: All official agency reports cited in the proposed
rule have undergone extensive internal review, and some have solicited
outside peer review. Articles cited from scientific journals have all
received formal peer review. Although the Service relies primarily on
final documents in making listing decisions, the best available
information may also come from other sources such as written
correspondence, factual information and data from draft documents,
expert opinions, and personal communications. The Service strives to
evaluate the accuracy of this ``gray literature'' before considering it
in making a listing decision.
26. Comment: Several individuals commented on the methods and
results of certain reports used by the Service in the proposed rule,
including three USGS reports (Slade et al. 1985, 1986; Veenhuis and
Slade 1990) and a Barton Springs/Edwards Aquifer Conservation District
(BS/EACD) report (Hauwert and Vickers 1994). The Service was also
criticized for not making available for public review and comment the
raw data upon which these and other reports cited by the Service are
based.
Service Response: The reports cited in the proposed rule and in
this final rule present sufficient information and data needed to
review and assess the methodologies used by the investigators, their
study results and data analyses, and conclusions. The Service has
reviewed these reports and determined that the data were gathered and
analyzed in accordance with sound scientific principles, and accepts
these reports as valid and relevant scientific information.
Furthermore, the results and conclusions of independent studies
consistently show similar trends regarding impacts of urbanization on
water quality and quantity. The USGS and BS/EACD have both provided
written responses to the criticisms of their reports (Raymond Slade,
USGS, in litt. 1994; Nico Hauwert, BS/EACD in litt. 1995; Bill Couch,
BS/EACD, in litt. 1996).
27. Comment: The occurrence of turbidity, accumulation of
sediments, and contaminants in Barton Springs watershed could be due to
natural phenomena.
Service Response: The volume of sediments observed in urbanizing
portions of the Barton Springs watershed and increased turbidity during
periods of major construction indicate that such activities influence
these phenomena. As discussed in Factor A, the relationship between
urban runoff and increased erosion and sedimentation is well
documented. Increases in turbidity tend to coincide with land clearing
and construction activities, and discharge of turbid runoff from
construction projects has been observed entering receiving waters in
the Barton Springs watershed.
Research shows that the contaminants discussed in Factor A
(including elevated levels of nutrients, heavy metals, petroleum
hydrocarbons, and pesticides) are primarily associated with urban
runoff. The Service is unaware of any natural sources in the Barton
Springs watershed that could result in significant concentrations (or
any detectable concentrations for manmade compounds such as pesticides)
of these contaminants in water.
28. Comment: A report by T.U. Taylor (in litt. 1922) states that
elevated levels of fecal coliform bacteria have been documented at
Barton Springs since 1922. However, the Service stated in the proposed
rule that the City of Austin determined that the method used to measure
bacterial counts at the time of the report is different from that used
today, and thus ``the bacterial counts are not directly comparable to *
* * current sampling techniques'' (Austin Librach, City of Austin, in
litt., 1991). The City of Austin's review of the report does not
provide a basis for refuting its conclusions or excluding them from
further consideration. The comparison of fecal coliform counts taken in
the context of the standards of the time, to counts taken today and in
the context of today's standards, is a valid comparison.
Service Response: To date, the Service has only been provided a
copy of a cover letter (dated August 28, 1922) to a supplementary
report submitted by Mr. Taylor to the City of Austin. The letter states
the need to filter Barton Springs water for human consumption due to
contamination with ``B. coli.'' Because no report accompanied the
letter, and the Service has been unable to obtain a copy of the report,
the Service can draw no further conclusions regarding its findings.
29. Comment: What is the basis for the Service's statement that
``contaminants that adsorb to the surface of sediments may be
transported through the aquifer and later be released back into the
water column ''?
Service Response: The Service based this statement on information
presented in Schueler (1987), which states that once deposited,
pollutants in ``enriched sediments can be remobilized under suitable
environmental conditions posing a risk to benthic life'' (see Factor
A).
30. Comment: The Service received a comment letter that contained a
document comparing the findings and conclusions of the proposed rule
with those made in a report by the Aquatic Biological Advisory Team
(ABAT), which concluded that insufficient information appears to exist
to support a listing decision.
Service Response: The City of Austin and Texas Parks and Wildlife
Department formed the ABAT, which consisted of five nationally
recognized specialists, to make research and management recommendations
needed to conserve the Barton Springs and Bull Creek watersheds and
their resident salamander populations (the Barton Springs and
Jollyville Plateau salamanders). The ABAT members were specifically
instructed not to make recommendations regarding listing nor to
evaluate specific laws or regulations. The Service believes that
substantial evidence exists to support a listing determination for the
Barton Springs salamander, but also recognizes that additional research
is important to assist in making sound management recommendations. The
Service concurs with most of the ABAT's management recommendations,
which could be incorporated into a regional management plan for the
Barton Springs watershed, as well as a recovery plan for the Barton
Springs salamander.
31. Comment: The TNRCC and TxDOT provided information regarding
existing and proposed rules and regulations, which they state are
adequate to protect the Barton Springs salamander.
Service Response: An evaluation of the existing rules and
regulations is provided in Factor D of this final rule. The Service
encourages State and local entities to identify proposed regulations
and additional protective measures that can serve as a basis for a
regional management plan for the Barton Springs watershed.
Summary of Factors Affecting the Species
After thorough review and consideration of all information
available, the Service has determined
[[Page 23384]]
that the Barton Springs salamander should be classified as an
endangered species. Procedures found at section 4 of the Act and
regulations implementing the listing provisions of the Act (50 CFR part
424) were followed. A species may be determined to be endangered or
threatened due to one or more of the five factors described in section
4(a)(1). These factors and their application to the Barton Springs
salamander (Eurycea sosorum Chippendale, Price, and Hillis) are as
follows:
A. The present or threatened destruction, modification, or
curtailment of its habitat or range. The primary threat to the Barton
Springs salamander is degradation of the quality and quantity of water
that feeds Barton Springs resulting from urban expansion over the
Barton Springs watershed (including roadway, residential, commercial,
and industrial development). A discussion of some potential effects of
contaminants on the salamander and its prey base (amphipods) is
provided in this section and under Factor E. Potential factors
contributing to declining water quality and quantity in this portion of
the Edwards aquifer include chronic degradation, catastrophic hazardous
material spills and increased water withdrawals from the aquifer. Also
of concern are impacts to the salamander's surface habitat.
Urbanization can dramatically alter the normal hydrologic regime
and water quality of an area. As areas are cleared of natural
vegetation and topsoil and replaced with impervious cover (paved
surfaces), rainfall no longer percolates through the ground but instead
is rapidly converted to surface runoff. Creekflow shifts from
predominantly baseflow, which is derived from natural filtration
processes and discharges from local groundwater supplies, to
predominantly stormwater runoff. The amount of stormwater runoff tends
to increase in direct proportion to the amount of impervious cover.
With increasing stormflows, the amount of baseflow available to sustain
water supplies during drought cycles is diminished and the frequency
and severity of flooding increases. The increased amount and velocity
of runoff increases erosion and streambank destabilization, which in
turn leads to increased sediment loadings, channel widening, and
changes in the morphology and aquatic ecology of the affected creek
(Schueler 1991). Sediment from soil erosion is ``by volume the greatest
single pollutant of surface waters and is the potential carrier of most
pollutants found in water'' (Menzer and Nelson 1980).
Urbanization introduces many pollutants into an area, including
suspended solids, nutrients, petroleum hydrocarbons, bacteria, heavy
metals, volatile organic compounds, fertilizers, and pesticides (TWC
1989; EPA 1990; Schueler 1991; Notenboom et al. 1994; Menzer and Nelson
1980). Stormwater runoff is a primary source of water pollution.
Pollutant loadings in receiving waters, particularly in areas that have
little or no pollution controls, generally increase with increasing
impervious cover (Schueler 1991). A report by the USGS on the
relationship between urbanization and water quality in streams
throughout the Austin area (9 of 18 sample sites were along streams in
the Barton Springs segment and its contributing zone) demonstrated
statistically significant increases in constituent concentrations with
increasing impervious cover (Veenhuis and Slade 1990). Degradation of
water quality in the Barton Springs watershed is also evidenced by
algal blooms, erosion, trash and debris, and accumulations of sediments
and toxics (City of Austin 1995).
Water quality in the aquifer and at Barton Springs is directly
affected by the quality of water in the six creeks that cross the
recharge zone (see Background section). Of these creeks, water quality
at Barton Springs responds most rapidly to changes in water quality in
Barton Creek (Slade et al. 1986; City of Austin 1991). Data show that
contaminants in Barton Creek can enter the aquifer near Barton Springs
and discharge from the springs within hours or days of storm events
(Slade et al. 1986; City of Austin 1991). Because groundwater
originating from Barton Creek remains in the aquifer for short periods
before discharging at the springs, there is little time for attenuation
of pollutants before discharging at Barton Springs (Slade et al. 1986;
City of Austin 1991). Increases in turbidity (a measure of suspended
solids or sediment), algal growth, nutrients, and fecal-group bacteria
have been documented along Barton Creek between SH 71 and Loop 360 and
at Barton Springs, and have been largely attributed to construction
activities and the conveyance and treatment of sewage in this area
(Slade et al. 1986; Austin Librach, City of Austin in litt., 1990; City
of Austin 1991, 1993; Barbara Britton, TWC, in litt., 1992).
Water quality in the more heavily developed areas of the Barton
Springs segment and at Barton Springs is also beginning to show signs
of degradation (Slade et al. 1986; Librach in litt., 1990; City of
Austin 1991, 1993; Slade 1992; Hauwert and Vickers 1994; Texas
Groundwater Protection Committee (TGPC) 1995). The BS/EACD found
elevated levels of sediment, fecal-group bacteria, trace metals,
nutrients, and petroleum hydrocarbons in certain springs and wells
between Sunset Valley and Barton Springs (Hauwert and Vickers 1994,
TGPC 1994). Slade et al. (1986) reported that levels of fecal-group
bacteria, nitrate nitrogen, and turbidity were highest in wells near
creeks draining developed areas. In addition to sediments and bacteria,
tetrachloroethene, a commonly used drycleaning solvent, has been
detected in water samples from Barton Springs (Slade 1991). Possible
sources of groundwater contamination include urban runoff, construction
activities, leaking septic tanks and pipelines, and petroleum storage
tank releases (Slade et al. 1986; TWC 1989; EPA 1990; Hauwert and
Vickers 1994).
One of the most immediate threats to the Barton Springs salamander
is siltation of its habitat, owing primarily to construction activities
in the Barton Creek watershed (Slade et al. 1986, City of Austin 1991,
Hauwert and Vickers 1994, TGPC 1994). Major highway, subdivision, and
other construction projects along Barton Creek increased during the
early 1980's and 1990's. While high turbidity has been observed in
Barton Springs Pool following major storm events since the early 1980's
(Slade et al. 1986; Hauwert 1995), the duration and frequency of
sediment discharges from Barton Springs increased substantially during
the 1990's (Hauwert 1995; TGPC 1994). Barton Springs discharged large
amounts of sediments following most major rain events in 1993, 1994
(Hauwert and Vickers 1994; TGPC 1994), and 1995 (Collett, pers. comms.,
1994-1995). Sediments have been observed emanating directly from the
spring outlets in Barton Springs Pool (Doyle Mosier, Lower Colorado
River Authority; Debbie Dorsey, City of Austin; pers. comms., 1993;
Collett and Hansen, pers. comms., 1994-1995) about 8 to 12 hours
following the start of a heavy rain (Slade et al. 1986; City of Austin
1991; Hauwert and Vickers 1994; David Johns, City of Austin, pers.
comm. 1996).
Several uncased wells in the Barton Creek watershed, one of which
is located 5 km (3 mi) south of Barton Springs near the Loop 360
bridge, have been completely filled with a cream-colored, carbonate
silt (up to 45 m (150 ft)) (Hauwert and Vickers 1994). A well in Sunset
Valley measured 1 to 1.5 ft accumulations of cream-colored sediment
over an eight-month period prior to July 1993, and reportedly
[[Page 23385]]
caused the well pump to seize (Hauwert and Vickers 1994). Several well
owners, drillers, and operators also reported a significant influx of
sediments during 1993, particularly during periods of heavy rainfall
and low water-level conditions (Hauwert and Vickers 1994).
Studies have shown that high levels of suspended solids reduce the
diversity and density of aquatic fauna (EPA 1986; Barrett et al. 1995).
In Barton Springs Pool, the lowest recorded population counts of the
salamander (ranging from 1 to 6 individuals) occurred over the five-
month period following an October 1994 flood event (see Background
section). The flood deposited a large amount of silt and debris over
the salamander's habitat in the pool, and the area occupied by the
salamander during the following months was reduced to the silt-free
areas immediately adjacent to the spring outlets (Hansen, in litt.,
1995c).
In addition to covering the salamander's habitat, problems
resulting from increased sediment loads may include: Clogging of the
gills of aquatic species, causing asphyxiation (Garton 1977; Werner
1983; Schueler 1987); smothering their eggs and reducing the
availability of spawning sites (EPA 1986; Schueler 1987); filling
interstitial spaces and voids, thereby reducing water circulation and
oxygen availability (EPA 1986); filling and blocking of recharge
features and underground conduits, restricting recharge and groundwater
storage volume and movement; reducing light transmission needed for
photosynthesis, food production, and the capture of prey by sight-
feeding predators (EPA 1986; Schueler 1987); and exposing aquatic life
to contaminants that readily bind to sediments (such as petroleum
hydrocarbons and heavy metals). Once deposited, pollutants in
``enriched sediments can be remobilized under suitable environmental
conditions, posing a risk to benthic life'' (Schueler 1987).
Research indicates that species in or near contaminated sediments
may be adversely affected even if water-quality criteria are not
exceeded (Landrum and Robbins 1990; Medine and McCutcheon 1989).
Sediments act as a sink for many organic and inorganic contaminants
(Menzer and Nelson 1980; Landrum and Robbins 1990; Medine and
McCutcheon 1989) and can accumulate these contaminants to levels that
may impact aquatic ecosystems (Landrum and Robbins 1990; Medine and
McCutcheon 1989). Metal-contaminated sediment toxicity studies have
shown Hyallela azteca, the primary food item of the Barton Springs
salamander, to be the most sensitive organism of those tested (Phipps
et al. 1995; Burton and Ingersoll 1994). Most polycyclic aromatic
hydrocarbons (PAHs), a component of oil, are associated with sediments
in aquatic ecosystems, which may be ingested by benthic organisms
(Eisler 1987). Hyallela azteca has been shown to assimilate PAHs from
contaminated sediments (Eisler 1987). Sediments collected from the main
stem of Barton Creek on November 21, 1994, about 150 m above Barton
Springs Pool, contained several PAHs that were 2.5 to 22 times the
levels shown to always have a toxic effect (survival, growth, or
maturation) on Hyallela azteca (City of Austin, unpubl. data, 1994;
Ingersoll et al., in press). Sediments collected from Barton Springs on
April 20, 1995, also contained PAHs at levels up to 6.5 times those
shown to be toxic to Hyallela azteca (City of Austin, unpubl. data,
1995; Ingersoll et al., in press).
In addition to sediment concentrations, high levels of total
petroleum hydrocarbons have been detected in water samples from Sunken
Garden Springs (Hauwert and Vickers 1994). Petroleum hydrocarbons
include both aliphatic hydrocarbons and PAHs (Albers 1995). Normal
concentrations of petroleum hydrocarbons in the Edwards aquifer are
below the detection limit of 1.0 mg/l. However, levels of total
petroleum hydrocarbons measured 1.9 mg/l following a 9-mm (0.35-in)
rain event in March 1994, and 1.3 mg/l in April 1994. A well that is
hydrologically connected with Barton Springs contained a level of 2.1
mg/l in May 1993 (Hauwert and Vickers 1994; BS/EACD 1994). Petroleum
hydrocarbons may enter water supplies through sewage effluents, urban
and highway runoff, and chronic leakage or acute spills of petroleum
and petroleum products (Eisler 1987; Hauwert and Vickers 1994; Albers
1995).
Water samples from Sunken Garden Springs also contained elevated
levels of lead, which are commonly found in petroleum-contaminated
waters. Total and dissolved lead levels at Sunken Garden Springs
measured 0.024 and 0.015 mg/l, respectively (Hauwert and Vickers 1994;
BS/EACD 1994). Typical freshwater concentrations for lead are between
0.001 and 0.01 mg/l (Menzer and Nelson 1980). The EPA drinking water
standard for total lead is 0.015 mg/l. In aquatic environments,
dissolved lead is the most toxic form, and adverse effects (including
reduced survival, impaired reproduction, and reduced growth) on aquatic
biota have been reported at concentrations of 0.001 to 0.005 mg/l
(Eisler 1988a). Sources of lead in water may include industrial
discharges, highway runoff, and sewage effluent (Pain 1995).
Aquatic organisms may absorb lead through skin, gills, intestines,
and other organs, and may ingest lead through feeding (Pain 1995). Lead
concentrations tend to be highest in benthic organisms, which may
assimilate lead directly from sediments (Eisler 1988a). Research
indicates that lead is not essential or beneficial to living organisms,
and that all known effects are deleterious, including those on
survival, growth, reproduction, development, behavior, learning, and
metabolism (Eisler 1988a; Pain 1995). Adverse effects increase with
elevated water temperatures, reduced pH, younger life stages, and long
exposures (Eisler 1988a; Pain 1995). Synergistic and additive effects
may also occur when lead is mixed with other metals or toxic chemicals
(Eisler 1988a). Studies have shown that lead is highest in urban
streams and lowest in rural streams, and that species diversity is also
greater in rural streams than urban ones (Eisler 1988a).
Arsenic, which has been used in the manufacture of agricultural
pesticides and other products (Eisler 1988b) and may be found in
roadway and urban runoff, has been detected in wells in the Barton
Springs watershed at levels exceeding EPA drinking water standards
(0.05 mg/l) (Hauwert and Vickers 1994) and in other areas of Texas (TWC
1989). Concentrations of arsenic compounds adversely affecting aquatic
biota have been reported at 0.019 to 0.048 mg/l (Eisler 1988b).
Toxicity of arsenic to aquatic life depends on many factors, including
water temperature, pH, suspended solids, organic content, phosphate
concentration, presence of other contaminants, arsenic speciation, and
duration of exposure. As with many contaminants, early life stages are
most sensitive, and large differences in responses exist between
species (Eisler 1988b).
Leaking underground storage tanks ``are considered to be one of the
principal contributing sources of ground-water pollution, placing a
significant loading on the State's aquifers, due to their regional
distribution and high number which are estimated to be leaking'' (TWC
1989). Chronic releases from leaking tanks represent a serious risk of
water contamination (City of Austin 1994). The TNRCC (1994) lists
leaking underground storage tanks as one of the top three most
frequently encountered sources of groundwater contamination in the
Edwards aquifer. Common pollutants from leaking underground storage
tanks include gasoline, diesel,
[[Page 23386]]
and other oil products (TWC 1989). The TNRCC's ``Leaking Petroleum
Storage Tank Case Report'' lists 626 leaking petroleum storage tanks
for Hays and Travis counties for the period between October 1984 and
April 1995, of which 158 cases resulted in some form of groundwater
contamination. Fifteen of the reports specifically identified impacts
to the Edwards aquifer, of which only three had been officially closed
or were near closure.
The conveyance and treatment of sewage in the watershed,
particularly in the recharge zone, may also impair water quality.
Sewage effluent may contain organics (including PAHs), metals,
nutrients (nitrogen and phosphorus), inorganic acids, and
microorganisms (Eisler 1987; Menzer and Nelson 1980; TWC 1989; City of
Austin 1991, 1993; Notenboom et al. 1994). Sewage contamination has
occurred at Barton Springs following major rain events (TWC 1989), and
high bacterial counts and algal blooms have been reported (Slade et al.
1986; City of Austin 1991). In 1982, high levels of fecal coliform
bacteria at Barton Springs were attributed to a sewerline leak upstream
from Barton Springs Pool. While fecal coliform bacteria are believed to
be harmless, they indicate the presence of other organisms that may be
pathogenic to aquatic life (Lager et al. 1977), some of which may pose
a threat to salamanders and/or their prey base.
Wastewater discharges have been identified as a primary cause of
algal blooms, which have been a recurring problem in both Barton Creek
and at Barton Springs (City of Austin 1991, 1993). Increased nutrients
promote eutrophication of aquatic ecosystems, including the growth of
bacteria, algae, and nuisance aquatic plants, and lowered oxygen
levels. Menzer and Nelson (1980) note that ``changes in nutrient pools
must eventually directly affect the productivity of the entire
ecosystem, even though the effects may not be measurable in biologic
terms until a number of years later.'' Because most nutrients in urban
runoff are present in soluble form and are thus readily consumed by
algae, nutrient concentrations present in urban runoff tend to
stimulate algal blooms (Schueler 1987). A 5 km-(3-mi) long algal bloom
observed along Barton Creek in April 1993 may have been the result of
an accidental discharge of 1.6 million liters (440,000 gallons) of
effluent and irrigation water from a golf course (City of Austin 1993,
1995).
Based on USGS data (Slade et al. 1986), the average level of
nitrates at Barton Springs Pool has increased from about 1.0 mg/l
(measured as nitrate nitrogen) prior to 1955 to a 1986 level of about
1.5 mg/l. Sunken Garden Springs measured greater than 2.0 mg/l nitrate
nitrogen during the BS/EACD study (Hauwert and Vickers 1994). Elevated
nitrate concentrations in groundwater are attributed primarily to human
activities (TWC 1989). Total nitrogen (as nitrogen) concentrations
measured in wells in the more urbanized areas of the Barton Springs
watershed are typically two to six times higher than in rural areas
(Slade 1992). Elevated levels of total phosphorus and orthophosphorus
have also been detected in certain springs and wells in the Barton
Springs watershed (Slade 1992; Hauwert and Vickers 1994). In addition
to wastewater discharge, other possible sources of nutrients in the
Barton Springs watershed include fertilizers, solid wastes, animal
waste, and decomposition of natural vegetation (Hauwert and Vickers
1994; Slade et al. 1986).
Over 145 km (90 mi) of wastewater lines occur in the recharge zone
of the Barton Springs segment (Maureen McReynolds, City of Austin Water
and Wastewater Utility, pers. comm., 1993). Most of the creeks
contributing recharge to the Barton Springs segment are underlain by
wastewater lines, and five wastewater treatment plants are located
within the Barton Springs watershed (City of Austin 1991). Leaking
septic tanks and inadequate filtering in septic fields have also been
identified as a major source of groundwater contamination, particularly
for older systems (TWC 1989; EPA 1990; City of Austin 1991; Hauwert and
Vickers 1994; TNRCC 1994). The TNRCC (1994) cites septic tanks as the
most frequently encountered source of groundwater contamination in the
Edwards aquifer. Although the amount of effluent leached from an
individual septic system may be small, the cumulative impact over the
landscape can be significant, especially for karst aquifers (EPA 1990).
An estimated 4,800 septic systems currently exist in the Barton Springs
watershed and may contribute as much as 23 percent of the total
nitrogen load to the aquifer (City of Austin 1995).
Highways can have major impacts on groundwater quality (TNRCC 1994;
Barrett et al. 1995). The TNRCC (1994) lists highways and roads as the
fifth most common potential source of groundwater contamination in the
Edwards aquifer. Elevated concentrations of metals, Kjeldahl nitrogen,
and organic compounds have been detected in groundwater near highways
and their control structures. Highway construction can also cause large
increases in suspended solids to receiving waters (Barrett et al.
1995). Several major highways have been built over the recharge zone
since the late 1980's, and the expansion of US 290 from SH 71 through
Oak Hill to a six-lane freeway is underway. US 290 crosses the Barton
Creek watershed and discharges stormwater runoff from detention ponds
into tributaries of Barton Creek. Bypass events from a regional water
quality pond at the US 290/Loop 360 interchange have resulted in
significant sediment deposition along the entire length of an unnamed
tributary and a portion of Barton Creek (City of Austin, in litt. 1995;
City of Austin, unpubl. data, 1996; USFWS, in litt. 1996), less than 5
km (3 mi) from Barton Springs.
Organophosphorus pesticides commonly used in urban areas tend to
degrade rapidly in the environment, but certain pesticides may remain
biologically active for some time (Eisler 1986, Hill 1995). For
example, diazinon, which is commonly used in commercial and residential
areas, may remain biologically active in soils for up to 6 months under
conditions of low temperature, low moisture, high alkalinity, and lack
of microbial degraders (Eisler 1986). Diazinon has shown adverse
effects on stream insects at concentrations of 0.3 micrograms/l (Eisler
1986). To ensure protection of sensitive aquatic fauna, Eisler (1986)
recommends that levels of diazinon in water not exceed 0.08 micrograms/
l. Many organophosphorus compounds may result in adverse effects after
short-term exposures. Exposure may include contact with or ingestion of
contaminated water, sediments, or food items (Hill 1995).
Increasing urbanization also increases the risk of catastrophic
spills. Because of the Barton Springs salamander's limited range, a
single catastrophic spill has the potential to impact the entire
species and its habitat. Catastrophic spills can result from major
transportation accidents, underground storage tank leaks, pipeline
ruptures, sewage spills, vandalism, and other sources. Because no
designated route for hazardous materials exists for the Austin area,
potentially hazardous materials may be transported on major roadways
crossing the Barton Springs watershed (City of Austin 1994). Expansion
of major roadways and increasing volumes of traffic, particularly
across the recharge zone near Barton Springs, increases the threat of
catastrophic spills.
Oil pipeline ruptures also represent a source of groundwater
contamination with potentially catastrophic
[[Page 23387]]
consequences. Three oil pipelines run roughly parallel to each other
across the Barton Springs watershed and cross Barton Creek near the
Hays/Travis county line. Two of these lines have ruptured within the
recharge zone about 13 km (8 mi) south of Barton Springs, which
constitute the largest spills reported from Hays and Travis counties
between 1986 and 1992 (TWC, unpubl. data). The first major spill
occurred in 1986, about 270 m (300 yards) from Slaughter Creek, when an
oil pipeline was severed during a construction operation and released
about 366,000 liters (96,600 gallons) of oil. Although about 91 percent
of the spill was reportedly recovered (Rose 1986), petroleum
hydrocarbon fumes were detected about six weeks later in caves located
up to 2.7 km (1.7 mi) northeast of the spill (Russell 1987). The second
pipeline break occurred in 1987 near the first spill site and released
over 190,000 liters (49,000 gallons) of oil. According to the TWC
database, more than 97 percent of this spill was recovered (TWC,
unpubl. data).
Response times to hazardous materials spills vary, depending on
several factors including detection capability, location and size of
the spill, weather conditions, whether or not the spill is reported,
and the party performing the cleanup. In some cases, spills may go
undetected and/or unreported. Generally, cleanup is initiated within
several hours once the spill has been detected and reported, but many
weeks or possibly years may be necessary to complete the cleanup
effort. In areas where access is difficult (due to remoteness, steep
terrain, or other factors), remediation may not be possible or may be
ineffective due to delays in initiating cleanup.
Increased demands on water supplies from the aquifer can also
reduce the quality and quantity of water in the Barton Springs segment
and at Barton Springs. The volume of springflow is regulated by the
level of water in the aquifer. Discharge decreases as water storage in
the aquifer drops, which historically has resulted primarily from a
lack of recharging rains rather than groundwater withdrawal for public
consumption. During these low flow conditions, ``bad water'' within the
San Antonio segment of the Edwards aquifer may move northward and
contribute to flows from Barton Springs (Slade et al. 1986; Stein
1995). In addition, increased withdrawals could result in upward
leakage from the underlying Trinity aquifer, which has higher levels of
dissolved solids and fluoride than water in the Barton Springs segment
(Slade et al. 1986).
Under low flow conditions, Barton Springs and a well near the bad
water line (YD-58-50-216) have shown increased dissolved solids
concentrations, particularly sodium and chloride, indicating
encroachment of bad water (Slade et al. 1986). The BS/EACD (Hauwert and
Vickers 1994) measured high levels of dissolved solids at Sunken Garden
Springs, indicating a significant influence of bad water during low
flow conditions. The potential for encroachment of the bad water line
and/or recharge from the Trinity aquifer increases with pumpage of the
aquifer and extended low recharge or low flow conditions (Slade et al.
1986). The encroachment of bad water could have negative impacts on the
plants and animals associated with Barton Springs. High sodium and
chloride levels have been shown to increase fish mortality by
disturbing ion balances (Werner 1983).
Based on water-budget analyses and pumpage estimates for 1982
(Slade et al. 1985, 1986), discharge from the Barton Springs segment
(withdrawal plus springflow) was determined to be roughly equal to
recharge from surface waters. Thus, a substantial increase in
groundwater withdrawal would be expected to cause a decrease in the
quantity of water in the aquifer and discharge from Barton Springs. The
estimated total pumpage in 1982 was 470 hectare-meters (3,800 acre-
feet), or about 10 percent of the long-term mean discharge of 1,400 l/s
(50 cfs) for Barton Springs (Slade et al. 1985, 1986). The BS/EACD
estimated total pumpage for 1994 to be about 570 hectare-meters (4,600
acre-feet) (Botto and Rauschuber 1995). The exact volume of water that
is pumped from the aquifer is difficult to estimate, since meter
reports are only required for municipal, industrial, irrigation, and
commercial wells and not for wells that pump less than 38,000 l (10,000
ga) per day, domestic wells, or agricultural wells used for non-
commercial livestock and poultry operations (BS/EACD 1994). Groundwater
pumpage increases considerably and its effects on aquifer levels and
springflows become more pronounced during dry spells (Slade et al.
1986; D.G. Rauschuber & Associates and R.J. Brandes Co. 1990; BS/EACD
1994; Nico Hauwert and Ron Fiesler, BS/EACD, pers. comms., 1995).
The number of wells in the Barton Springs segment is growing with
the increasing dependence on the Edwards aquifer for drinking water,
irrigation, and industrial use (BS/EACD 1994 and 1995; Botto and
Rauschuber 1995). In the 235 sq mi area of the Barton Springs segment,
a total of 54 new wells were drilled between fiscal year (FY) 1989
(September 1, 1988 to August 31, 1989) and FY 1993, with a maximum of
18 wells drilled during a single year (BS/EACD 1995). During FY 1994,
46 new wells were drilled, which is more than two and a half times the
number drilled in FY 1993 (BS/EACD 1994). An additional 45 wells were
drilled in FY 1995 (BS/EACD 1995). As urbanization in the outlying
areas of Austin expands and reliance on groundwater supplies increases,
the number of wells and the total volume of water withdrawal is also
expected to continue to increase.
In addition to contributing to declining groundwater supplies, the
TWC (1989) cites water wells as a major source of groundwater
contamination by providing direct access of pollutants into the aquifer
and possibly through inter-aquifer transfer of bad water. Reduced
groundwater levels exacerbate the problem through decreased dilution of
pollutants.
Under the 1996 pumping and drought regime, flows from Barton
Springs approached historically low conditions. Because the flows from
Eliza and Sunken Garden springs are considerably less than flows from
the main springs in Barton Springs Pool (see Background section), the
impacts of increased groundwater withdrawals and drought are realized
more quickly for these spring outlets. As of July 1996, the water level
in both Eliza Pool and Sunken Garden Springs was less than a foot deep
(O'Donnell, pers. obs., 1996). Both springs ceased flowing during the
drawdown of Barton Springs Pool (Hansen, pers. comm., 1996; O'Donnell,
pers. obs. 1996).
Other potential impacts to the salamander's surface habitat may
include the use of high pressure fire hoses in areas where the
salamander occurs, hosing silt from the shallow end of Barton Springs
Pool into the salamander's habitat, diverting water from Sunken Garden
Springs into Barton Creek below Barton Springs, and runoff from the
train station above Eliza Pool. Following the 1992 fish kill (see
Background section), chlorine is no longer used to clean Barton Springs
Pool. The City of Austin has drafted a management plan to avoid,
minimize, and mitigate impacts to the salamander from pool cleaning and
other park maintenance practices.
Impervious cover over the Barton Springs watershed is currently
estimated at 4 to 6 percent (Slade 1992; City of Austin 1995). This
area is under increasing pressure from urbanization (Austin
Transportation Study (ATS) 1994). The ATS has projected that the Austin
metropolitan area will support a
[[Page 23388]]
population of over 1.3 million by the year 2020, up from 815,000 in
1994. Southwest Austin, which covers only a portion of the Barton
Springs watershed, is projected to almost double in size, from an
estimated 32,000 people in 1994 to 58,000 by the year 2020. Likewise,
the population in northern Hays County is expected to more than triple
in size by the year 2020, from 18,000 in 1994 to 68,000 in 2020 (ATS
1994). According to the Capital Area Planning Council (CAPCO), Hays
County has the second highest growth rate in the ten-county CAPCO
region. Dripping Springs, which is located in the contributing zone
between Onion Creek and Barton Creek, ``will likely continue to
experience a high rate of growth as development continues along U.S.
290 from the Oak Hill area westward'' (CAPCO 1990).
Several major highways, including a segment of State Highway 45,
the southern extension of Loop 1 (``MOPAC''), and the Southwest Parkway
have been built in the last decade to accommodate the projected
population growth, real estate speculation, and traffic demands in this
area. Justification for the Highway 290 expansion was largely based on
the population growth projected for and already occurring in this area
(ATS 1994). In addition to these roadways, the remainder of State
Highway 45, an 82-mi loop around Austin, is proposed to be built within
the next 20 to 25 years. This highway would cross Barton Creek and
several other creeks in the Barton Springs watershed (City of Austin
1994).
Less than 2,400 ha (6,000 ac) of preserve lands currently exist in
the Barton Springs watershed (USFWS 1996). Much of the remaining area
along Barton Creek and within the City of Austin's Extra-territorial
Jurisdiction (ETJ) is slated for development at levels of greater than
30 percent impervious cover (City of Austin unpubl. data).
B. Overutilization for commercial, recreational, scientific, or
educational purposes. No threat from overutilization of this species is
known at this time.
C. Disease or predation. No diseases or parasites of the Barton
Springs salamander have been reported. Primary predators of the Barton
Springs salamander are believed to be predatory fish and crayfish;
however, no information exists to indicate that predation poses a major
threat to this species.
D. The inadequacy of existing regulatory mechanisms. No existing
rules or regulations specifically require protection of the Barton
Springs salamander or the Barton Springs ecosystem, and no
comprehensive plan is in place to protect the Barton Springs watershed
from increasing threats to water quality and quantity. The salamander
is not included on the TPWD's list of threatened and endangered
species, so the species is not protected by that agency.
Since the publication of the proposed rule, the City of Austin's
``Save Our Springs'' (SOS) ordinance was overturned by a Hays County
jury in November 1994 (Jerry J. Quick, et al. v. City of Austin). Prior
to its invalidation, the SOS ordinance was the most stringent water
quality protection regulation in the Barton Springs watershed,
requiring impervious cover limitations of 15 to 25 percent (based on
net site area), buffers along major creeks, no increases in loadings of
13 pollutants, barring of exemptions and variances from the ordinance
provisions, and attempts to reduce the risk of accidental contamination
(Camille Barnett, City of Austin, in litt., 1993).
In addition to the overturning of the SOS ordinance, several bills
passed during the State's 74th (1995) legislative session that curtail
the City of Austin's ability to implement water quality protective
measures within its five-mile ETJ. Senate Bill 1017 and House Bill 3193
exempt large developments (over 1,000 acres, or 500 acres if approved
by the TNRCC) from all City of Austin water quality ordinances and land
use regulations. The TNRCC has determined that this legislation
conflicts with State and Federal regulations; does not address
groundwater quality; is inadequate to ensure protection of surface
water quality and would not meet State water quality standards;
provides little or no inspection, enforcement, or compliance
safeguards; and would allow surface and groundwater quality to degrade
(Mark Jordan, TNRCC, in litt., 1995). Other laws passed during the 1995
session that limit the enforcement authority of local governments
include Senate Bill 14, which allows landowners to sue local and State
governments to invalidate regulations or seek compensation for actions
that would decrease property values by 25 percent or more; and Senate
Bill 1704, which ``grandfathers'' developers from updated health and
safety ordinances.
Other laws and regulations potentially affecting water quality in
the Barton Springs watershed include the Federal Clean Water Act, Safe
Drinking Water Act, Resource Conservation and Recovery Act, and
Comprehensive Environmental Response, Compensation, and Liability Act;
the Edwards Rules and Texas Underground Storage Tanks Act (30 Texas
Administrative Code, Chapters 313 and 334), which are promulgated and
enforced by the TNRCC; the City of Austin's water quality protective
ordinances (Williamson Creek Ordinance (1980), Barton Creek Watershed
Ordinance (1981), Lower Watersheds Ordinance (1981), Comprehensive
Watersheds Ordinance (1986), ``Composite Ordinance'' (1991), and the
amended Composite Ordinance (1994); and the City of Dripping Springs'
Site Development Ordinance 52B. In addition to the inadequacies of
these rules and regulations (discussed below), many of the agencies
charged with their administration lack adequate resources to carry out
their responsibilities (TNRCC 1994).
The purpose of the Clean Water Act is ``to restore and maintain the
physical, chemical, and biological integrity of the Nation's waters.''
Section 304 of the Clean Water Act provides the EPA authority to
develop water quality criteria to protect water resources, including
groundwater. However, the primary focus of the Clean Water Act is on
surface water, and the law does not mandate protection of groundwater
resources. Furthermore, surface and groundwater tend to be treated as
separate and distinct resources rather than interactively, and
protection focuses on human use rather than effects on aquatic
organisms. Section 302, which provides for a National Pollution
Discharge Elimination System (NPDES), primarily addresses point source
pollution and not non-point source pollution or groundwater
contamination. Efforts are needed to integrate the relationship between
surface and groundwater into the regulatory framework and to assess the
impact of surface water regulations and management practices on
groundwater resources.
Part C of the Safe Drinking Water Act, the Underground Injection
Control Program, requires that the injection of fluids underground not
endanger drinking water supplies. Section 1427 (Sole Source Aquifer
Program) requires that federally funded projects potentially affecting
a sole source aquifer ensure that drinking water will not be
contaminated. A portion of the Barton Springs watershed has been
designated as a Sole Source Aquifer. The Sole Source Aquifer Program
applies only to Federal projects and not to State or private projects,
unless they receive Federal funds, and no requirements related to
aquatic organisms are included.
[[Page 23389]]
The Federal Resource Conservation and Recovery Act (RCRA) and
Comprehensive Environmental Response, Compensation, and Liability Act
focus on remedial actions once groundwater contamination has occurred,
rather than on prevention. Under these Acts, monitoring is required to
determine when remediative cleanup actions following groundwater
contamination by chemical and waste sites is complete. In addition, the
RCRA requires that all underground storage tanks installed since 1988
be equipped with spill and overfill protection devices, protected from
corrosion that could result in releases, and equipped with devices that
would detect any releases that might occur. Previously existing tanks
are to be upgraded to these same standards over a ten-year period.
Much of the responsibility for protecting surface and groundwaters
is directed to and administered by the states. Section 106 of the Clean
Water Act provides funds to the states for water quality programs,
including comprehensive groundwater protection programs. Section 303
requires states to set water quality standards for surface waters,
employing the criteria established by the EPA under section 304, and to
designate uses for each water body. Section 319 provides technical and
financial assistance to the states to implement programs to control
nonpoint source pollution for both surface water and groundwater. The
EPA's policy, ``Protecting the Nation's Groundwater: EPA's Strategy for
the 1990's'' also recognizes states as having the primary role of
protecting groundwater. Section 1428 of the Safe Drinking Water Act,
the Wellhead Protection Program, directs states to control sources of
contaminants near public supply wells used for drinking water. Most of
the State of Texas' efforts to protect surface and groundwater
resources focus on point sources of pollution, monitoring, and
remediative actions (TNRCC 1994). The TNRCC's Tier II Antidegradation
Policy applies only to regulatory actions that would exceed fishable/
swimmable quality of Barton and Onion creeks, and allows degradation if
necessary for important economic or social development.
The Edwards Rules regulate construction-related activities on the
recharge zone of the Edwards aquifer that may ``alter or disturb the
topographic, geologic, or existing recharge characteristics of a site''
as well as any other activity ``which may pose a potential for
contaminating the Edwards aquifer,'' including sewage collection
systems and hazardous materials storage tanks. The Edwards Rules
regulate construction activities though review of Water Pollution
Abatement Plans (WPAPs). The WPAPs do not require site-specific water
quality performance standards for developments over the recharge zone
nor do they address land use, impervious cover limitations, nonpoint
source pollution, application of fertilizers and pesticides, or
retrofitting for developments existing prior to the implementation of
the Rules. (Travis County was incorporated into the Rules in March
1990; Hays County was incorporated in 1984.) The WPAPs also do not
apply to development activities in the aquifer's contributing zone. To
date, the Edwards Rules do not include a comprehensive plan to address
the effects of cumulative impacts on water quality in the aquifer or
its contributing zone.
The Edwards Rules and the Texas Underground Storage Tanks Act
(Title 31, Chapters 313 and 334 of the Texas Administrative Code)
require that all tanks installed after September 29, 1989, be equipped
with release detection devices, corrosion protection, and spill/
overflow protection; that all previously existing tanks be upgraded to
the same standards by December 22, 1994; and that tanks located in the
Edwards aquifer recharge and transition zones be of double-walled or
equivalent construction with continuous monitoring of the space between
the tank and piping walls for leak detection. The adequacy of these
measures in preventing groundwater contamination, particularly over the
long term, has not been demonstrated. Routine testing of tanks to
ensure proper functioning is not required until after a leak has been
detected, and no routine monitoring or testing by the TNRCC is
conducted to determine compliance with the regulations. Formal approval
by the TNRCC of construction plans for new tanks is only required for
the recharge zone and not the contributing zone. The TNRCC does not
maintain a database of the total number of storage tanks that have been
upgraded, those that still need to be upgraded, or those that are in
violation of the regulations (Jackie Hardee, TNRCC, pers. comm., 1995).
A Section 10(a)(1)(B) permit allowing the incidental taking of two
endangered songbirds and six endangered karst invertebrates, known as
the Balcones Canyonlands Conservation Plan (BCCP), was issued to Travis
County and the City of Austin in May 1996 (USFWS 1996). The BCCP does
not allow incidental taking of the Barton Springs salamander, and
requires that all permit applicants ensure that their activities do not
degrade waters in the Barton Springs watershed. The guidance provided
in the Available Conservation Measures section of this final rule is
intended to assist landowners in achieving this goal. Acquisition of
4,000 acres in the Barton Creek watershed as BCCP preserve land will
provide additional benefits to the salamander by preserving the natural
integrity of the landscape and positively contributing to water quality
and quantity in Barton Creek and Barton Springs. The BCCP does not
apply to development activities in Hays County.
To protect water quantity in the Barton Springs segment, the BS/
EACD has developed a Drought Contingency Plan (D.G. Rauschuber &
Associates and R.J. Brandes Co. 1990). Barton Springs has always flowed
during recorded history, and one of the BS/EACD's goals is to assure
that Barton Springs flow ``does not fall appreciably below historic low
levels'' (D.G. Rauschuber & Associates and R.J. Brandes Co. 1990). The
BS/EACD regulates about 60 to 80 percent of the total volume that is
pumped from the Barton Springs segment and has the ability to limit
development of new wells, impose water conservation measures, and
curtail pumpage from these wells during drought conditions (Bill Couch,
BS/EACD, pers. comm., 1992, and in litt. 1994; Botto and Rauschuber
1995). According to the BS/EACD (B. Couch, pers. comm., 1992), water
well production in the higher elevations of the Barton Springs segment
has been limited during periods of lower aquifer levels in recent
years. However, the ability of the BS/EACD to ensure the success of the
plan is limited, since it does not regulate 20 to 40 percent of the
total volume that is pumped from the Barton Springs segment.
E. Other natural or manmade factors affecting its continued
existence. The very restricted range of the Barton Springs salamander
makes this species especially vulnerable to acute and/or chronic
groundwater contamination. Since the salamander is fully aquatic, there
is no possibility for escape from contamination or other threats to its
habitat. A single incident (such as a contaminant spill) has the
potential to eliminate the entire species and/or its prey base.
Crustaceans, particularly amphipods, on which the salamander feeds are
especially sensitive to water pollution (Mayer and Ellersieck 1986;
Phipps et al. 1995; Burton and Ingersoll 1994).
Research indicates that amphibians, particularly their eggs and
larvae, are sensitive to many pollutants, such as heavy metals; certain
insecticides,
[[Page 23390]]
particularly cyclodienes (endosulfan, endrin, toxaphene, and dieldrin),
and certain organophosphates (parathion, malathion); nitrite; salts;
and petroleum hydrocarbons (Harfenist et al. 1989). Christine Bishop
(Canadian Wildlife Service) states that ``the health of amphibians can
suffer from exposure to pesticides (Harfenist et al. 1989). Because of
their semipermeable skin, the development of their eggs and larvae in
water, and their position in the food web, amphibians can be exposed to
waterborne and airborne pollutants in their breeding and foraging
habitats * * *. [Furthermore] pesticides probably change the quality
and quantity of amphibian food and habitat (Bishop and Pettit 1992).''
Toxic effects to amphibians from pollutants may be either lethal or
sublethal, including morphological and developmental aberrations,
lowered reproduction and survival, and changes in behavior and certain
biochemical processes.
Observations of central Texas Eurycea salamanders in captivity
indicate that these species, including the Barton Springs salamander,
are very sensitive to changes in water quality and are ``quite delicate
and difficult to keep alive'' (Sweet, in litt., 1993). Sweet reported
that captive individuals exhibit adverse reactions to plastic
containers, aged tapwater, and detergent residues. The water in which
these salamanders are kept also requires frequent changing (Sweet, in
litt., 1993). Unsuccessful attempts at captive propagation of the San
Marcos salamander (Janet Nelson, Southwest Texas State University,
pers. comm., 1992) and very limited success at inducing captive
spawning in the Barton Springs salamander (Ables, Coale, and Dwyer,
pers. comms., 1996) may also be due to these species' sensitivity to
environmental stress.
Several citizens have expressed concern over impacts to the
salamander from recreational use of Barton Springs Pool for swimming.
However, no evidence exists to indicate that swimming in Barton Springs
Pool poses a threat to the salamander population, which is located 3 to
5 m (10 to 15 ft) below the water's surface. The survey data show no
correlation between recreational use of the pool and salamander
abundance. Furthermore, salamander population declines have occurred in
Eliza Pool, which is closed to the public. Although certain pool
maintenance practices may impact individual salamanders occurring in
the pools, they are unlikely to have a major impact on the entire
species.
The Service has carefully assessed the best scientific and
commercial information available regarding the past, present, and
future threats faced by this species in determining to make this rule
final. The best scientific data indicate that listing the Barton
Springs salamander as endangered is warranted. Critical habitat is
determined to be not prudent for this species for the reasons discussed
below.
Critical Habitat
Critical habitat is defined in section 3 of the Act as: (i) The
specific areas within the geographical area occupied by a species, at
the time it is listed in accordance with the Act, on which are found
those physical or biological features (I) essential to the conservation
of the species and (II) that may require special management
considerations or protection; and (ii) specific areas outside the
geographical area occupied by a species at the time it is listed, upon
a determination that such areas are essential for the conservation of
the species. ``Conservation'' means the use of all methods and
procedures needed to bring the species to the point at which protection
under the Act is no longer necessary.
Section 4(a)(3) of the Act, as amended, and implementing
regulations (50 CFR 424.12) require that, to the maximum extent prudent
and determinable, the Secretary designate critical habitat at the time
the species is determined to be endangered or threatened. Service
regulations (50 CFR 424.12(a)(1)) state that designation of critical
habitat is not prudent when one or both of the following situations
exist--(1) The species is threatened by taking or other human activity,
and identification of critical habitat can be expected to increase the
degree of such threat to the species, or (2) such designation of
critical habitat would not be beneficial to the species. The Service
finds that designation of the springs occupied by the Barton Springs
salamander as critical habitat would not be prudent because it would
not provide a conservation benefit to the species.
Designation of critical habitat benefits a listed species only when
adverse modification or destruction of critical habitat could occur
without the survival and recovery of the species also being
jeopardized. Because the Barton Springs salamander is restricted to one
area that discharges water from the entire Barton Springs watershed,
any action that would result in adverse modification or destruction of
the salamander's critical habitat would also jeopardize its continued
survival and recovery. Designating critical habitat would therefore not
provide a benefit to the species beyond the benefits already provided
by listing and subsequent evaluation of activities under the jeopardy
standard of section 7 of the Act. Because jeopardy to the species and
adverse modification of its critical habitat are indistinguishable, the
Service has determined that designation of critical habitat for the
Barton Springs salamander is not prudent.
Available Conservation Measures
Conservation measures provided to species listed as endangered or
threatened under the Act include recognition, recovery actions,
requirements for Federal protection, and prohibitions against certain
practices. Recognition through listing encourages and results in public
awareness and conservation actions by Federal, State, and local
agencies, private organizations, and individuals. The Act provides for
possible land acquisition and cooperation with the States and requires
that recovery actions be carried out for all listed species. The
protection required of Federal agencies and the prohibitions against
taking and harm are discussed, in part, below.
The health of the aquifer and Barton Springs, and the long-term
survival of the Barton Springs salamander, can only be ensured through
a concerted, organized effort on the part of all affected Federal,
State, and local governments and the private citizenry to protect the
Barton Springs watershed. Conservation and management of the Barton
Springs salamander will entail removing threats to its survival,
including--(1) protecting the quality and quantity of springflow from
Barton Springs by implementing comprehensive management programs to
control and reduce point and nonpoint sources of pollution throughout
the Barton Springs watershed; (2) minimizing the risk and likelihood of
pollution events that would affect water quality; (3) strengthening
efforts to protect groundwater and springflow quantity; (4) continuing
to examine and implement pool cleaning practices and other park
operations that protect and perpetuate the salamander's surface habitat
and population; and (5) public outreach and education. It is also
anticipated that listing will encourage continued research on the
critical aspects of the Barton Springs salamander's biology (e.g.,
longevity, natality, sources of mortality, feeding and breeding
ecology, and sensitivity to contaminants and other water quality
constituents).
Section 7(a) of the Act, as amended, requires Federal agencies to
evaluate their actions with respect to any species that is proposed or
listed as endangered
[[Page 23391]]
or threatened and with respect to its critical habitat, if any is
designated. Regulations implementing this interagency cooperation
provision of the Act are codified at 50 CFR Part 402. Section 7(a)(1)
requires Federal agencies to use their authorities to further the
purposes of the Act by carrying out programs for listed species.
Section 7(a)(2) requires Federal agencies to ensure that activities
they authorize, fund, or carry out are not likely to jeopardize the
continued existence of a listed species. If a Federal action may affect
a listed species, the responsible Federal agency must enter into
consultation with the Service, unless the Service agrees with the
agency that the action is not likely to adversely affect the species.
The Act and its implementing regulations set forth a series of
general prohibitions and exceptions that apply to all endangered
wildlife. These prohibitions, codified at 50 CFR 17.21, in part, make
it illegal for any person subject to the jurisdiction of the United
States to take (includes harass, harm, pursue, hunt, shoot, wound,
kill, trap, or collect, or to attempt any of these), import or export,
ship in interstate commerce in the course of commercial activity, or
sell or offer for sale in interstate or foreign commerce any listed
species. It also is illegal to possess, sell, deliver, carry,
transport, or ship any such wildlife that has been taken illegally.
Certain exceptions apply to agents of the Service and State
conservation agencies. The Barton Springs salamander is not known to be
commercially traded and such permit requests are not expected.
Permits may be issued to carry out otherwise prohibited activities
involving endangered wildlife species under certain circumstances.
Regulations governing permits are at 50 CFR 17.22 and 17.23. Such
permits are available for scientific purposes, to enhance the
propagation or survival of the species, and/or for incidental take in
connection with otherwise lawful activities.
It is the policy of the Service (59 FR 34272; July 1, 1994) to
identify to the maximum extent practicable at the time a species is
listed, those activities that would or would not constitute a violation
of section 9 of the Act. The intent of this policy is to increase
public awareness of the effect of listing on proposed and ongoing
activities within a species' range, and to assist the public in
identifying measures needed to protect the species. Aside from the
potential for catastrophic spills, no single development activity or
water withdrawal in and of itself is likely to significantly impact
water quality and quantity in the Barton Springs watershed. Rather, it
is the sum of all of these activities and their associated impacts that
threaten this resource and the survival of the Barton Springs
salamander. Because most of the threats to the salamander come from
diffuse sources that are cumulative in nature, their effects will be
observable at the ecosystem and population level rather than at the
individual level. Thus, the purpose of this guidance is not only to
identify activities that would or would not likely result in ``take''
of individuals, but activities that in combination will ultimately
affect the long-term survival of the Barton Springs salamander. This
guidance should not be used to substitute for local efforts to develop
and implement comprehensive management programs for the Barton Springs
watershed.
Activities that the Service believes are unlikely to result in a
violation of section 9 for the Barton Springs salamander are:
(1) Range management and other agricultural practices that promote
good vegetative cover and soil conditions (for example, low to moderate
stocking rates, rotational and deferred grazing, and maintaining native
bunchgrasses);
(2) Swimming in Barton Springs pool;
(3) Buying or selling of property;
(4) Improvements to existing structures, such as renovations,
additions, repairs, or replacement;
(5) New developments or construction that do not result in an
appreciable change in the quality or quantity of water in the Barton
Springs watershed above normal background conditions (non-degradation).
Generally, new developments and construction designed and implemented
pursuant to State and local water quality protection regulations in
effect as of the date of this rule will not result in a violation of
section 9;
(6) Routine residential lawn maintenance; and
(7) Upgrading or replacing existing structures (such as bridge
crossings, BMPs, septic systems, underground storage tanks) in order to
minimize pollutant loadings into receiving waters.
Activities that the Service believes could potentially harm the
Barton Springs salamander and result in a violation of section 9
include:
(1) Collecting or handling of the species without appropriate
permits;
(2) Alteration or disturbance of the Barton Springs salamander's
habitat in the pools where it occurs (including use of chemicals to
clean the pools where the salamander occurs; use of high pressure fire
hoses in salamander habitat; removal of beneficial aquatic plants;
dredging; and frequent and/or prolonged drawdown, particularly during
drought);
(3) Illegal discharges or dumping of chemicals, silt, sewage,
fertilizers, pesticides, heavy metals, oil, organic wastes, or other
pollutants into the Barton Springs watershed;
(4) New developments or construction not designed and/or
implemented pursuant to State and local water quality protection
regulations in effect as of the date of this rule, that result in an
appreciable change in the quality or quantity of water in the Barton
Springs watershed above normal background conditions (non-degradation);
(5) Withdrawal of water from the aquifer to the point at which
springflows at Barton Springs appreciably diminish;
(6) Withdrawal of water from the contributing zone to the point at
which baseflows in the creeks appreciably diminish;
(7) Introduction of non-native aquatic species (fish, plants,
other) into Barton Springs or the Barton Springs segment of the Edwards
aquifer;
(8) Destruction or alteration of caves, sinkholes, or other
significant recharge features (including dumping, vandalism, and/or
diverting contaminated water into these features); and
(9) Destruction or alteration of spring orifices that provide water
to Barton Springs.
Questions as to whether specific activities will constitute a
violation of section 9 should be directed to the Service's Austin
Ecological Services Field Office (see ADDRESSES section). Requests for
copies of the regulations regarding listed wildlife and inquiries
regarding prohibitions and permits should be addressed to the U.S. Fish
and Wildlife Service, Branch of Endangered Species/Permits, P.O. Box
1306, Albuquerque, New Mexico 87103 (telephone: 505/248-6920;
facsimile: 505/248-6922).
National Environmental Policy Act
The Fish and Wildlife Service has determined that Environmental
Assessments and Environmental Impact Statements, as defined under the
authority of the National Environmental Policy Act of 1969, need not be
prepared in connection with regulations adopted pursuant to section
4(a) of the Endangered Species Act of 1973, as amended. A notice
outlining the Service's reasons for this determination was published in
the Federal Register on October 25, 1983 (48 FR 49244).
[[Page 23392]]
Required Determinations
The Service has examined this regulation under the Paperwork
Reduction Act of 1995 and found it to contain no information collection
requirements.
References Cited
A complete list of all references cited in this rule is available
upon request from the Austin Ecological Services Field Office (see
ADDRESSES section).
Author: The primary author of this final rule is Lisa O'Donnell,
Austin Ecological Services Field Office (see ADDRESSES section).
List of Subjects in 50 CFR Part 17
Endangered and threatened species, Exports, Imports, Reporting and
recordkeeping requirements, and Transportation.
Regulation Promulgation
Accordingly, part 17, subchapter B of chapter I, title 50 of the
Code of Federal Regulations, is amended as set forth below:
PART 17--[AMENDED]
1. The authority citation for part 17 continues to read as follows:
Authority: 16 U.S.C. 1361-1407; 16 U.S.C. 1531-1544; 16 U.S.C.
4201-4245; Pub. L. 99-625, 100 Stat. 3500, unless otherwise noted.
2. Section 17.11(h) is amended by adding the following, in
alphabetical order under AMPHIBIANS, to the List of Endangered and
Threatened Wildlife, to read as follows:
Sec. 17.11 Endangered and threatened wildlife.
* * * * *
(h) * * *
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Species Vertebrate
------------------------------------------------------ population where When Critical
Historic range endangered or Status listed habitat Special rules
Common name Scientific name threatened
--------------------------------------------------------------------------------------------------------------------------------------------------------
* * * * * * *
AMPHIBIANS
* * * * * * *
Salamander, Barton Springs...... Eurycea sosorum.... U.S.A. (TX) Entire............. E 612 NA NA
* * * * * * *
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Dated: April 24, 1997.
John G. Rogers,
Acting Director, Fish and Wildlife Service.
[FR Doc. 97-11194 Filed 4-29-97; 8:45 am]
BILLING CODE 4310-55-P