Habitat Conservation Plan for the Endangered Species of the Edwards Aquifer System


There are seven endangered species in the Edwards aquifer system.  There is one threatened species.  Federal law requires that the Edwards aquifer be managed for these species, as stated in the Endangered Species Act. Because of the unique geology of the Edwards Aquifer System, many of these species are endemic, that is, they do not occur anywhere else; therefore conservation of these species in the Edwards Aquifer is particularly crucial.

About 100 million years ago, the Edwards Aquifer began forming when Central Texas was covered by shallow seas.  Thirty-five million years later, the seas receded inland and deposited layers of shells and coral, the remains of which are the porous, honeycombed limestone rock of the Edwards Aquifer that is known today.

            The Edwards Aquifer extends over 176 miles from Brackettville in Kinney County to Kyle in Hays County.  The limestone of the Edwards Aquifer occurs in three distinct segments: the drainage area, the recharge area, and the artesian/reservoir area (EAA brochure). 

The drainage area is the largest component of the aquifer system.  It spans over 4,400 square miles.  The drainage area is a catchment area where rainfall infiltrates the cavernous water table aquifer which forms spring fed streams that flow downhill, over older impermeable formations until they reach the recharge zone (EUWD).

Geologically, the recharge zone is known as the Balcones fault line.  It encompasses 1,500 square miles, and spans 7 counties.  However, the Nueces River basin, the Frio-Sabinal basins and the Seco-Hondo-Medina basins (located in Medina, Uvalde, and Kinney Counties) supply about 70 percent of the total recharge to the aquifer.  The surface of the recharge zone contains an abundance of permeable and porous limestone that provides the path for the water to reach the artesian area (EAA).

The artesian/reservoir area is sandwiched between relatively impermeable younger formations and relatively impermeable older formations.  These formations confine the water in the porous Edwards limestone under pressure.  Due to this pressure, some of the water is forced to the surface through geological faults, known as springs. 

Water leaving the aquifer is known as discharge.  Water can be discharged by natural springs or through flowing and pumped wells EAA.  Most discharge occurs in the natural springs in San Antonio, New Braunfels, and San Marcos.  Pumping accounts for the second largest amount of discharge. 


Species of Concern

There are seven species that are listed endangered in the Edwards Aquifer system, and one is threatened.  The first endangered species, the Texas Blind Salamander (Typhlomolge rathbuni) was listed endangered on March 11, 1967.  It is a sightless and troglobitic salamander.  It is white or pinkish in color with a fringe of gills.  It has a flattened head and snout and long, slender limbs.  It has four toes on the fore legs and five on the hind legs.  Maximum length is 12-13 centimeters at maturity (USFWS p. 46).

            The Texas Blind Salamander is aquatic and occupies the subterranean waters of the Edward’s Aquifer.  It is a neotenic species that feeds on insects and other small invertebrates, such as amphipods and blind shrimp, living in the water that are nourished by bat droppings.  Gravid females have been found throughout the year.  Year-long sexual activity is expected because there is little seasonal change in the aquifer (USFWS 48). 

            The first Texas Blind Salamander found was in the artesian well of the Federal Fish Hatchery in 1895.  The species has been found in several other locations since then, Ezell’s Cave, San Marcos Springs, Rattlesnake Cave, Primer’s Fissure, Southwest Texas State University’s artesian well, and Frank Johnson’s well.  Currently, there is only one population of the Texas Blind Salamander that is known to biologists.  The population occurs in the Edward’s Aquifer around the city of San Marcos.  The distribution may be limited to as small as 10 km.  Although the current population is of limited numbers it appears to be stable.  No critical habitat has been designated.(USFWS p.48)

            The survival of the Texas Blind Salamander depends on the continued stability and purity of the springflows.  It is threatened by diminished springflows, pollution of groundwater, and runoff caused by excessive demand for water and development over the recharge zone (Eckhardt).     

            Current conservation measures include the purchase of Ezell’s cave in 1967, which has since been designated as a National Natural Landmark by the National Park Service.  Captive breeding has been successful at both the Cincinnati Zoo and the Dallas Aquarium.  The Dallas Aquarium plans to develop a captive breeding program which will include photodocumentation of embryological and larval development to provide more information on the reproductive ecology of the species.  National Park Service has funded the San Marcos NFH&TC to collect and distribute the Texas Blind Salamander to one or two other facilities for captive breeding (USFWS 50). 

The fountain darter (Eurycea nana) was listed endangered on October 13, 1970.  It is a reddish brown darter that is usually less than 25 cm in length.  It has dark, horizontal lines along the middle of the sides, and three dark spots on the base of the tail (USFWS p.30). 

            The fountain darter feeds on aquatic insect larvae, such as dipteran and ephemeropteran larvae, and also small crustaceans.  It feeds primarily in daylight and prefers moving prey.  The darter spawns year round, peaking in early spring and August.  They deposit their eggs in vegetation and then provide no further parental care to their young (USFWS p.34). 

            The fountain darter’s original range included the sources, headwaters and sections of the San Marcos and Comal Rivers.  Its present distribution  includes the entire Comal aquatic ecosystem (Eckhardt).  Populations are also present from Spring Lake to the area between the San Marcos treatment plant outfall and the Blanco River (USFWS p. 35).  Critical habitat has been designated for the fountain darter as “Texas, Hays County; Spring Lake and its outflow, the San Marcos River, downstream approximately 0.5 miles below Interstate Highway 35 bridge”  (FR 35:16047).

            In 1976 Schenck and Whiteside estimated the fountain darter population in Spring Lake to be about 103,000.  In 1993, Linam estimated fountain darter population in the San Marcos River to be 45,900 with a 90% confidence interval ranging from 15, 900 to 107,700.  Either fountain darter populations are declining, or the difference in population size is just due to different sampling methods.  In 1991, Janet Nelson surveyed Spring Lake with scuba-aide and estimated at least 16,000 darters at the spring opening, and another 15,000 in algae habitat.  Also, in 1990 G. Linam did seven transect samples in the Comal River and Landa Lake and estimated the population of fountain darters to be 168,078 with a 95% confidence interval from 114,178-254,110 (USFWS p.33).  With all the different sampling methods used, and the variety of places samples, it is difficult to reach a hard and fast number of the fountain darter populations.  It seems, pardon the pun, to just muddy the waters. 

            If the fountain darter is going to be protected, its requirements must be met. It requires undisturbed stream floor habitats.  It requires a mix of submergent vegetation, in part for cover.  Higher densities of the fish were found in mats of green algae.  The fountain darter needs clean and clear water, and a food supply of living organisms.  It requires constant water temperatures.  It can reproduce when held to temperatures between 6 and 27 C.  Their critical thermal maximum was 34.8 C.  The  fountain dater is threatened by destruction of the aquatic vegetation in Spring Lake and San Marcos River (USFWS p.33).  Divers and swimmers disturb the algae and destroy habitat.

            As for current conservation measures, habitat use is being studied and models created for instream flow requirements for the fountain darter.  No information is currently available.  Sampling of water temperature, DO, pH, and specific conductivity is currently being done to model water temperature at various spring and river discharges.  Genetic studies of the fountain darter populations in the San Marcos and Comal Ecosystems are being researched to determine genetic variation within and among darter populations.  A preliminary study is also being done to determine the toxicity of San Marcos wastewater effluent and the herbicide Rodeo to fountain darters (USFWS p. 35).   

            The San Marcos Gambusia (Gambusia georgei) was listed endangered on July 14, 1980.  It is thought to be already extinct.  Its length averaged 2.5 to 4 cm.  It had a bluish tint, strongly hatched scales, and lemon yellow median fins.  It also had a diffuse mid-lateral stripe along the length of its body (Eckhardt). 

            Food habits are unknown, but it is presumed to have eaten insect larvae and other invertebrates.  It is a livebearer (Eckhardt).  The San Marcos Gambusia was first recorded in 1884.  In 1968, there was a record of 119 collections of the San Marcos Gambusia.  However, since then, the number sampled has declined steadily.  The last known collection of the San Marcos Gambusia was in 1983.  The San Marcos Gambusia populations have always been sparse, and efforts are still being made to locate any populations in existence (USFWS p. 28).

            The Gambusia’s historic range was limited to a 1-kilometer section of the San Marcos near the city of San Marcos.  As far as habitat, the San Marcos Gambusia requires, above all, thermally constant waters, averaging about 23 C.  It needs quiet, shallow, and open water adjacent to sections of moving water.  The San Marcos Gambusia was found mostly over muddy substrates, but not silted habitats.  It prefers partial shading from overhanging trees or bridges.  It needs clean and clear water, and lastly, a food supply of moving organisms (USFWS p.29).  The San Marcos Gambusia has had critical habitat designated as “Texas, Hays County; San Marcos River from Highway 12 bridge downstream to approximately 0.5 miles below Interstate Highway 35 bridge” (FR 45: 47355-47364).

            The San Marcos Gambusia had extremely specific habitat requirements, and so very sensitive to habitat alteration of any kind.  Changes in water temperatures from low springflows, water turbidity changes from land clearing and construction runoff could have eliminated the species (Eckhardt).  There have also been reports of hybridization between G. georgei and G. affinis.  It was not considered a threat because hybrids were in low numbers compared to pure San Marcos Gambusia.  However, between 1981-1983, collections taken indicate that hybrids have become much more abundant than the pure G. georgei, indicating that it could have been genetically swamped out of existence.  It is also possible that these hybrids are competing with G. georgi and placing additional strain on any remaining populations (USFWS p. 29). 

            Captive breeding was attempted in 1979 and 1980, however, both captive populations hybridized with another Gambusia, and the pure stocks were lost.  From 1981-1984, a search ensued to reestablish a culture for captive refugia, but too few were found to reestablish it (USFWS p.30). 

            Texas Wild Rice (Zizania texana) was listed endangered on April 26, 1978.  It is an aquatic, perennial grass.  Its average height is 1-2 m.  Its leaves are linear, elongate and green.  Flowering can occur throughout the year in warm weather, but is most typical in spring and fall (Eckhardt).  The plant reproduces by seeds or stolons.  Studies indicate that it is predominantly outbreeding and wind-pollinated.

            Historically, Texas Wild Rice was once abundant in the San Marcos River and in Spring Lake at the river headwaters.  Its current distribution is located in the upper four miles of the San Marcos River Near the city of San Marcos (Eckhardt).  Critical Habitat has been designated for Texas Wild Rice as “Texas, Hays County; Spring Lake and its outflow, the San Marcos River, downstream to its confluence with the Blanco River” (FR 45: 47355-47364). 

            Texas Wild Rice forms clones in the middle of the river in limestone sand and gravel shallows.  It prefers swiftly flowing currents of high quality water.  It also prefers the constant year-round temperatures that adequate springflows provide.  It is threatened by silting, disturbance of the bottom and stagnant water (Eckhardt).  It is possibly threatened by predation by nutria and waterfowl.  There is also concern about the potential impact by recreationists, tubers and swimmers in particular (USFWS p.46). 

.            Texas Wild Rice is particularly threatened by decreased spring outflow because it exposes the shallows that make up its typical habitat.  Dredging and damming of the river, bottomland cultivation, and riverside construction also threats to Texas Wild Rice because it destroys plants, alters stream flows and temperature or increases siltation (Eckhardt). 

            There have been attempts to cultivate and transplant wild rice, but success has been limited.  A new population was established in Salado Creek in the 1970’s, but the plants were disturbed by recreationists.  Nursery grown plants were transplanted to several sites in central Texas between 1976 and 1982, but resulted in no new populations.    Attempts are underway to begin a public education program to minimize disturbance by recreationists in the San Marcos River (Eckhardt). 

            The Comal Springs riffle beetle is small aquatic species.  It is surface dwelling.  Average length is 1/8 of an inch long; females are slightly larger than males.  It has short and non-functional wings. 

            It is not subterranean, but prefers gravel substrate and shallow riffles and runs that average 2 to 10 centimeters in depth.  Population density is greatest between February and April.  It has been collected from Comal Springs in Landa Park in runs 1,2, and 3.  It is also known to be found at San Marcos Springs.  It is not know whether it historically ranged to other springs as well (Eckhardt). 

            The Comal Springs Dryopid Beetle is a subterranean species that averages 1/8 of an inch long.  They are weakly pigmented, translucent, and have vestigial eyes. 

            It prefers flowing and uncontaminated water.  They are presumed to be associated with air-filled voids inside spring orifices.  The Comal Springs Dryopid Beetle does not swim.  It was first discovered in 1987, and is now primarily found at run 2 at Comal Springs, and also runs 3 and 4  from Comal and Fern Bank Springs.  Nothing is know about its historic range.  No specimens have been found in collections from 22 artesian and pumped wells flowing from the Edward’s Aquifer, suggesting that the species is likely confined to spring area openings and not distributed within the aquifer itself (Eckhardt). 

            Peck’s Cave Amphipod is an aquatic and subterranean species. It is unpigmented and eyeless.  It prefers crevices in rock and gravel near spring orifices.  Its primary habitat seems to be in the underground aquifer feeding the springs.  This interconnected area provides for feeding, growth, survival and reproduction of Peck’s Cave Amphipod.  It has been collected in Comal Springs and Hueco Springs.  Despite effort, no other specimens have been found in other areas of the aquifer, suggesting that the species is likely confined to spring area openings and not distributed within the aquifer itself (Eckhardt).

            The conservation and recovery of the aquatic invertebrates is similar and involves protecting and conserving springflow at Comal, Hueco, San Marcos and Fern Bank Springs.   The limited habitat for these species could be easily lost through drought, and especially by increased amount of human groundwater withdrawals.  Effects of reduced springflows include increases in temperature and temperature fluctuations, or a decrease in velocity, and a subsequent increase in siltation.  Groundwater contamination is another threat to these species made possible by pollutants such as human sewage, leaking underground storage tanks, animal/feedlot waste, urban runoff, and agricultural chemicals.  Other potential threats, especially in the urbanized areas of San Marcos and Comal Springs are pipeline, railway, and highway transportation of hydrocarbons and the possibility of accidents it brings.  All three require flowing water for respiration, and two of the species are fully aquatic, but no low water limits for survival are known (Eckhardt). 

            There is one threatened species of the Edward’s Aquifer, the San Marcos Salamander.  It was listed as threatened on July 14, 1980.  The San Marcos Salamander is lungless and neotenic.  It does not metamorphose into a terrestrial form, but sexually matures and breeds in the water.  It is small and slender and light brown with a dorsolateral row of pale spots on either side of the mid-line, and yellowish-white below.  It has relatively large eyes (Eckhardt). 

Historically this species was found in the sources and upper portions of the San Marcos River.  This salamander is now represented only by the San Marcos springs area populations.  Its limited range now compromises the San Marcos Springs, Spring Lake, and a few hundred feet of the San Marcos River.  The most recent population estimate is around 50,000 individuals (USFWS p.38).

The San Marcos Salamander requires thermally constant waters.  The salamanders become stressed at temperatures above 30 C.  However their critical thermal maximum of adults was 37.2, and for juveniles was 35.8.  It need flowing water for respiration.  It needs clean and clear water (don’t we all!).  The San Marcos Salamander prefers sand, gravel, and rock substrates with little mud or detritus.  It needs vegetation for cover from predators such as that afforded by cyanophycean bacteria.  The vegetation also supports a plentiful food supply for the salamander, also a requirement for the salamander (USFWS p.38). 

Critical habitat has been designated for the San Marcos salamander as “Texas, Hays County; Spring Lake and its outflow, the San Marcos River, downstream approximately 50m from the Spring Lake Dam” (FR 45:47355-47364).

Although the current population appears stable, it is threatened by degradation or modification of its limited habitat.  Residential and agricultural development and a rising demand for water may cause springs to run dry.  Controlling the amount of water pumped from the aquifer will be the key to preserving the San Marcos Salamander.

Current conservation measures include the development of captive breeding techniques at the Dallas Aquarium in the event that the population at San Marcos Springs is lost (USFWS p.41). 


Analysis of the USFWS Recovery Plan

            In response to legal pressure by the Sierra Club, the United States Fish and Wildlife Service (USFWS) researched and drafted the San Marcos and Comal Springs and Associated Aquatic Ecosystems (Revised) Recovery Plan (1996) to delineate the steps necessary for the effective management and recovery of the endangered species of the Edwards Aquifer springs.  The document reviews the biological knowledge pertaining to the federally listed species at the time: the San Marcos gambusia, fountain darter, Texas wild-rice, and Texas blind salamander.  Peck’s Cave amphipod, Comal Springs riffle beetle, and the Comal Springs dryopid beetle were listed in 1997, after the publication of the recovery plan.

            Loss of springflows from overpumping is the greatest threat to the endangered species of the Edwards Aquifer.  Human disturbance such as recreation and impermeable cover over the recharge and other factors that reduce water quality are also a threat.  With these threats in mind, the USFWS describes three recovery goals:

1) to secure the survival of these species in their native ecosystems;

2) to develop an ecosystem approach using strategies to address both local, site-specific, and broad regional issues related to recovery;

3) to conserve the integrity and function of the aquifer and spring-fed ecosystems that these species inhabit. (USFWS, executive summary, vi)


            These goals result from the Endangered Species Act, which prohibits the take, or unlicensed killing, directly or indirectly, of federally listed endangered species; the critical habitat must be conserved and managed for these to survive.  Therefore, this plan is more than just an effort to save the endangered species of the Edwards Aquifer.  Of course, that is the main goal, driven by the Endangered Species Act, but the USFWS hopes to protect all of the aquatic ecosystems, subsequently protecting the other plant and animal species there, as well as the water quality.

            The USFWS claims to take an ecosystem approach to address the conservation of the endangered species. Ecosystems management has become a buzzword in the conservation community that has never been clearly defined; each person who uses it defines it slightly differently.  Meffe and Carrol, eds. of Principles of Conservation Biology examine many of these different definitions and by taking their common thread, define ecosystems management as follows:

Ecosystems management is an approach to maintaining or restoring the composition, structure, and function of natural and modified ecosystems for the goal of long-term sustainability.  It is based on a collaboratively developed vision of future conditions that integrates ecological, socioeconomic, and institutional perspectives, applied within a geographic framework defined primarily by natural ecological boundaries (361-362).

An ecosystem approach involves decision-making by the whole community, from biologists to businessmen, and in turn, should benefit the whole community. 

            Community benefit, in terms of human services, is one of the strongest arguments for the USFWS recovery plan in particular, and management of the Edwards Aquifer in general.  San Antonio citizens will often ask why we should care about an eyeless lizard or some cave bug so much that we should stop watering our lawns.  Conservation biologists know the value of biodiversity, both biologically and perhaps existentially, but the benefits of saving these particular organisms can be made even more tangible to the citizenry.  That blind salamander serves as an indicator of the quality of the aquifer; it lives in the very water that San Antonians drink.  Therefore, if there is something wrong with the aquifer, water levels drop too low or the water becomes contaminated, we will know because the salamanders and other endangered species will begin dying out.  From a more positive perspective, if we manage the aquifer so as to keep those species alive, we will be protecting our own water supply.  San Antonio will have responsibly manage the Edwards Aquifer to maintain its long-term sustainability as a habitat and as a natural resource, benefiting the endemic species as well as the human community.

            Eventual delisting of federally listed organisms is the ultimate goal of the Endangered Species Act; however, in the case at hand, delisting is not possible due to the high degree of endemism in the Aquifer.  None of the currently listed endangered species found in the San Marcos and Comal Springs, as well as associated aquatic ecosystems, occur elsewhere.  A single catastrophic event such as a severe drought or large scale chemical spill could eliminate all the individuals of these species; therefore, these populations must always be managed to avoid their extinction.  A more reasonable goal is the eventual downlisting, from endangered to threatened, of the fountain darter, Texas wild-rice, and the Texas blind salamander (USFWS, 53-57).

            The USFWS recovery plan delineates specific measures necessary for the recovery of the endangered species.  The plan is divided into four sections: researching the biology of the endangered species, managing the species’ populations and habitats, monitoring those populations and habitats, and educating the public.  The Service’s recovery plan seems very provisional and preliminary.  It calls for the development of more specific water management plans and conservation plans.  It does suggest some more tangible plans of action, such as the establishment of captive breeding stocks in the case of a catastrophic loss of habitat.  The plan also suggests that non-native species be removed, pollution be reduced, and water quality be protected, although this seems rather vague.  The plan includes which organizations need to be involved, such as USFWS, the Texas Natural Resource Conservation Commission, the Texas State Legislature, and the Edwards Aquifer Authority, and how much it will cost each of them.  Overall, the plan would cost $3 million over the first three years, and $6 million through 2025, when the Service estimates that the fountain darter and TX wild rice can be downlisted if continual progress is made (USFWS, executive summary, vii). 

However, one of the plan’s weaknesses is that it does not (and cannot) provide incentive for the organizations mentioned to become involved.  The plan is fairly strong theoretically, but weak politically.  The plan begins with the disclaimer: 

Though the Service is responsible for developing this recovery plan, it cannot be implemented in its entirety without the assistance from other stakeholders...  This plan does not commit any ‘responsible party’ to carry out a particular recovery task or expend funds.  (USFWS, 58)

Since recovery in the Edwards Aquifer will require significant funds from responsible parties, recovery requires and incentive and legal backing.  The Edwards Aquifer Authority (EAA) is currently working on drafting a Habitat Conservation Plan (HCP), slated for release in February 2001 (www.e-aquifer.com), which will be able to provide for such incentives.  HCP’s facilitate management of the conservation of a habitat by requiring developers to compensate for taking endangered species.  Perhaps the plan can include a tax on impermeable ground cover that would go toward paying for conservation and for a water treatment plant that will be necessary if impermeable ground cover continues to increase.  The EAA should continue water price structuring such that increased water use results in higher water prices per gallon above a certain number of gallons per month.  Furthermore, this structuring should be advertised such that people will realize that saving water will save them money.  If we want people to conserve water, we must provide incentives, or they will not behave as though water is a limited resource.  Just last week, when the Express-News ran a front-page article warning about upcoming drought-induced water restrictions, I saw everyone in my neighborhood watering their lawns in the middle of the day, before the restrictions became active.  Such is the tragedy of the commons, where everyone tries to exploit a limited communal resource quickly, before others can get their hands on it.


Management of the Edwards Aquifer

Management of the Edwards Aquifer has been a controversial issue for over forty years. Conflicts between rural, urban, and industrial users have always been difficult to solve due to the unresolved issues of property rights and the question of who has the authority to set rules for distribution of this limited resource.  Currently, the Edwards Aquifer Authority (EAA) has the power to manage the water of the aquifer.  However, the State has declared the EAA unconstitutional then reversed this decision twice in its history since 1993.  The first time it was declared unconstitutional because it consisted of an appointed body rather than an elected one and thus violated voting rights.  The second time it was declared unconstitutional was due to the issue of property rights.  Another problem in aquifer management is that by the time water emergency plans are devised, the rain falls, then everything goes back to normal until there is another drought the following summer (Vottleter, 1998).  These events are just two examples of the frustration involved in water policy of the aquifer.

            This section analyzes the water policy process using an approach adapted from chapter 17 of our textbook (Meffe and Carroll, 1997).  Since the past legislation over the aquifer is complex, involving the entire city of San Antonio and the surrounding counties, this analysis will identify only the major participants and their goals, list possible solutions and their feasibilities, map social processes, and discuss current regulations. 

First, it is important to determine who actually owns groundwater, and the pumping rights and restrictions of property owners.

Who owns ground water?

Historically, groundwater policy was based on the “rule of free capture.”  “This rule essentially allows, with some exceptions, a landowner to pump as much groundwater as the landowner chooses, without liability to neighbors who claim that the pumping has depleted their wells (Fambrough, 2000).”  This is commonly referred to as the Big Pump Theory.  That is, the landowner with the biggest pump gets most of the water.  The exceptions to the rule of capture include that a landowner may not maliciously take water for the sole purpose of injuring a neighbor and that a landowner cannot wantonly and willfully waste it.  After the droughts of 1910 and 1917, the citizens of Texas enacted Section 59, Article 16 of the Texas Constitution giving the legislature the authority to pass laws in the interest of the “preservation and conservation of all such natural resources of the State (Fambrough, 2000).”  This article provided another exception to the rule of capture: districts created in the state have the authority to designate standards for the spacing of water wells and to regulate the production of water wells.  In 1978 another exception to the rule of capture was added: a landowner is liable for the subsidence of another’s land caused by the negligent withdrawal of groundwater (Fambrough, 2000). 

In 1991 Living Waters Artesian Springs Ltd. Began using as much as forty million gallons of aquifer water a day to raise catfish.  This usage is equal to 25% of the City’s total pumpage.  Under the rule of capture, the catfish farm could pump this much water without penalty as long as the pumping of other parties was not effected.  This extreme example of vulgar water use helped fuel the end to the rule of capture with the founding of the EAA (Votteler, 1998).  Texas property owners do not own the water beneath their land.  They own the right to drill and capture water as regulated by the EAA (Fambrough, 2000).


Analysis of Water Management

As stated in chapter 17, the policy process is about the shaping and sharing of values (power, wealth, enlightenment, skill, respect, rectitude, well-being, and affection) through social processes.  The water policy process will be analyzed by first identifying the participants, their goals, and their strategies (problem orientation); critique of various possible solutions; mapping social processes; and discussion of the current legislation on pumping.

I.                    Problem Orientation
A. Participants and their goals
The list of participants in the issue of water management includes all people of San Antonio as well as all people of the surrounding counties that depend on the Edward’s Aquifer.  These counties include Atacosa, Bexar, Calwell, Comal, Guadalipe, Hays, Medina, and Uvalde.  This case analysis will focus on the major participants involved in the legal battles over water management.  These participants are:  the government agencies such as the federal judiciary and the U.S. Fish and Wildlife Service (USFWS), and state agencies such as the Texas Water Commission; nongovernmental groups such as the Sierra Club, and the Guadalupe-Blanco River Authority (GBRA); and regional bodies such as the Edwards Underground Water District (EUWD) and its successor the Edwards Aquifer Authority (EAA). 
Of course, these different participants have conflicting goals.  The goal of the Sierra Club and that of the USFWS is to preserve the endangered species living in the aquifer and in Comal and San Marcos Springs which flow from the aquifer.  Their strategy is pressing charges against various other participants with violations to the Endangered Species Act.  These court cases will be outlined in a later section describing the legal history of the aquifer.  The goal of the GBRA is to preserve the Guadalupe River and Comal Springs, two tourist attractions that provide income for Hays and Comal counties.  Their strategy is to preserve the springs by enforcement of the ESA for the endangered species that live in these springs.  The EAA was created with the goal of regulating pumping of the aquifer, ensuring the quality of the water, and maintaining springflow above take levels as determined by USFWS.

B.     History of the Aquifer with respect to these goals

The following section is a summary of the major events in water legislation over the past fifty years. The history of the aquifer's management is presented with respect to the goals of the major participants as well as the strategies employed to achieve these goals.  This information will be important in the following section, an analysis of the policy process.  The following table summarizes the major events in water politics as discussed in this section and the following section.



Chronology of Edwards Aquifer Controversy






Prior to Pumping

Comal and San Marcos Springs, the largest springs in the

Southwest United States, have strong, continuous springflows at all times, even during major droughts.


Pumping increases to approximately 30,000 acre-feet per year.


The drought of record. Comal Springs dries up for five months in 1956.  Bad water line moves. In 1956 annual recharge is a record low 43,700 acre-feet and pumping reaches 321,000 acre-feet.


56th Legislature creates the Edwards Underground Water

District (EUWD) to protect and preserve the Edwards Aquifer.


U. S. Fish and Wildlife Service (USFWS) lists five aquatic species at Comal and San Marcos Springs as endangered or threatened.


EUWD builds four small recharge dams over the Edwards Aquifer.


San Antonio City Council rejects purchasing water from Canyon Reservoir.


USFWS designates critical habitat for four of the species at San Marcos Springs.


Flow at Comal and San Marcos Springs reaches critical levels during a brief drought.


San Marcos Recovery Plan adopted by USFWS.

January 1989

Uvalde and Medina Counties vote to pull out of the EUWD because of disagreement over pumping limits and establish single-county underground water districts.

June 15, 1989

Guadalupe-Blanco River Authority (GBRA) gives notice of violation under the Endangered Species Act (ESA). GBRA also files suit in State District Court to have the Aquifer declared an underground river owned by the State of Texas.


USFWS warns of the need to respond to excessive pumping and threatens limits.


A professional mediator is appointed by Texas Water Commission (TWC) to attempt to form a consensus about Aquifer regulation among various interests. No consensus emerges.

April 12, 1990

Sierra Club gives ESA notice of violation to USFWS.


The catfish farm opens southwest of San Antonio, using as much as 40 million gallons of water per day, by some estimates. In October, a suit filed in state district court shuts down the farm pending approval of a wastewater discharge permit.

May 16, 1991

Sierra Club, joined by GBRA and others, files a suit in the U. S. District Court in Midland, Texas.  The suit alleges the Secretary of the Interior and USFWS failed to protect endangered species dependent on the Aquifer.


November 1991

Texas Attorney General Dan Morales decides it is constitutional for the Texas Natural Resources Conservation Commission (TNRCC), which replaced TWC, to regulate groundwater.


Annual recharge is a record high 2,486,000 acre-feet.

March 1992

Attorney General Morales reverses his opinion that TNRCC has sufficient authority to regulate the use of groundwater.

April-August 1992

TNRCC adopts emergency rules finding that the Edwards

Aquifer is an underground river, subject to state regulation. A state district court invalidates TNRCC's declaration that the Aquifer is an underground river and voids the commission's new rules for the Aquifer.

February 1993

Judge Lucius Bunton finds for the plaintiffs, determining that if pumping from the Aquifer continues unabated, endangered and threatened species will be taken. TNRCC is directed to devise a plan by March 1, 1993 to limit pumping and preserve springflows. The plaintiffs can seek regulation by USFWS. USFWS is ordered to determine "take" and "jeopardy" flows for the Springs.

May 30, 1993

73rd Legislature enacts Senate Bill 1477 (S. B. 1477), creating the Edwards Aquifer Authority (EAA), to regulate groundwater use, abolishing EUWD.

June 15, 1993

USFWS determines takes and jeopardy flows for Comal and San Marcos Springs.

September 1993

S. B. 1477 takes effect, but implementation is delayed while the U.S. Department of Justice (USDOJ) decides whether the abolition of the EUWD elected board violates the Voting Rights Act.

November 19, 1993

USDOJ rules that S. B. 1477 does not meet the requirements of The Voting Rights Act because it would abolish an elected board (the EUWD).

June 6, 1994

Judge Bunton orders a Court Monitor to prepare a plan to limit Pumping by August 1, 1994, and also orders USFWS to publish a proposed recovery plan for the species by August 1, 1994.

August 1, 1994

Emergency Withdrawal Reduction Plan for the Edwards Aquifer is delivered to the court.

August 13, 1994

San Antonio voters decide in a referendum not to complete the Applewhite Reservoir.

September 25, 1994

Judge Bunton orders the formation of a panel, chaired by the Court Monitor, to draft a regional water management plan/habitat conservation plan to obtain an ESA Section 10(A) permit.

March 31, 1995

Revised Emergency Withdrawal Reduction Plan for the Edwards Aquifer filed with court.

April 28, 1995

Sierra Club files an ESA suit in Judge Bunton's court against USDA, alleging that USDA is allowing agricultural activities to harm species.


May 31, 1995

Governor George Bush approves changes to S. B. 1477 adopted by the 74th Legislature to give EAA an elected board to satisfy the concerns of USDOJ.

June 23, 1995

Draft Habitat Conservation Plan for the Edwards Aquifer

(Balcones Fault Zone-San Antonio Region) is distributed for comments.

August 23, 1995

A group led by the Medina and Uvalde County Underground Water Conservation Districts challenge to the constitutionality of S. B. 1477 (EAA) in state district court.

October 18, 1995

Monitor's activities are stayed by the Fifth Circuit Court of Appeals.

October 27, 1995

The state district court rules that S. B. 1477 is unconstitutional.

February 14, 1996

USFWS finishes the recovery plan, bringing the Sierra Club's suit against DOI to an end.


Drought returns to the region. Comal and San Marcos Springs rapidly drop to levels below jeopardy.

June 10, 1996

Sierra Club files a second ESA suit in Judge Bunton's court. The suit alleges that pumpers are causing takes of fountain darters as springflow declines.

June 28, 1996

Undivided Texas Supreme Court reverses state district court, and Finds that S. B. 1477 is constitutional.

July 2, 1996

Judge Bunton orders USDA to develop species conservation plan.

July 31, 1996

EAA board votes for a second time not to declare a water


August 1, 1996

Judge Bunton appoints the author as Special Master. The Special Master is ordered to develop a new water conservation plan within ten days.

August 23, 1996

After a public comment period, the 1996 Emergency Withdrawal Reduction Plan for the Edwards Aquifer is revised and adopted by the court. Judge Bunton declares a water emergency and issues an order setting a date for the plan's activation.

September 11, 1996

Judge Bunton's August 23, 1996 order is stayed by the Fifth Circuit Court of Appeals.

October 23, 1996

The Fifth Circuit grants USDA's motion for a stay pending appeal.

April 30, 1997

The Fifth Circuit vacates Judge Bunton's August 23, 1996 order, finding that the Court should have abstained from acting on a matter that the EAA could potentially handle.

December 18, 1997

USFWS lists Comal Springs riffle beetle, Comal Springs dryopid beetle, and Peck's cave amphipod as endangered.


After significant rains in 1997, drought returns to the region. Comal Springs drops to a level below take.


August 5, 1998

A State District Court issues a temporary injunction on behalf of the catfish farm, enjoining EAA from implementing or enforcing its rules that pertain to the filing and processing of permit applications.

August 14, 1998

Sierra Club notifies EAA and USFWS of intent to sue for violations of the ESA.

September 11, 1998

A second state district court enjoins EAA from enforcing its rules for issuing permits.

September 14, 1998

Environmental Defense Fund notifies EAA of intent to sue for violations of the ESA.

September 24, 1998

Ruling on an appeal of Judge Bunton's order, the Fifth Circuit finds that the ESA requires the USDA to develop programs to conserve endangered species.

December 17, 1998

Travis County court invalidates EAA permit rules and drought management plan.

  (Table adapted from table 4 of (Votteler, 1998)

For many years, the Edwards Aquifer has become the battleground for a myriad of competing interests, geographical, government, and corporate.  This section will provide a history of water use in South Texas and outline the major events in legislation of the aquifer.

San Antonio and its neighbors to the east and west sit on top of a rechargeable underground aquifer.  The aquifer's waters percolate to the surface at springs in the central (Bexar County) and eastern expanses of the aquifer (Hays and Comal Counties), which, in turn, have been sites of urban population growth.  Early settlements both prehistoric and historic, took advantage of the springs in the eastern part of the aquifer at San Marcos and in New Braunfels, as did the first settlers of San Antonio de Bexar to their west.  Water that traveled down the canals from San Pedro springs to San Antonio provided ample water for the irrigated fields located between the springs and what is today the city center.  The springs fed the San Antonio River, whose waster was tapped for irrigation as it moved south from the city center.  West of San Antonio were farmers  and ranchers who drew much of their water form shallow wells, using wind-driven pumps.  There seemed to be adequate water for all, humans and animals alike (Votteler, 1998, Donahue, 1998).

The groundwater policy during the frontier period was based on the "English rule" of free capture, meaning property owners could pump water from beneath their land as long as they did not waste it.  The rule of free capture never gave priorities of water usage, and thus never resolved conflicting interests among farmers, city-dwellers, recreationists, and industrialists across the region supplied by the Edwards Aquifer (Votteler, 1998, Donahue, 1998). 

The severe drought that occurred in 1950 and persisted till 1957 forced San Antonio to rethink the rule of capture and consider urban versus rural interests of the Aquifer.  Soon a regional government agency under state authority was created to plan for and acquire sources of water to recharge those found in the aquifer.  In 1959 the Texas legislature established, and voters approved, the creation of the Edwards Underground Water District.  All counties were represented in the district, but rural interests dominated.  The EUWD was authorized "to conserve, preserve, protect and increase the recharge of and prevent the pollution of the underground water (Donahue, 1998)," but it was not authorized to give the authority to restrict the rights of landowners to pump underground water from their lands (Votteler, 1998, Donahue, 1998). 

In 1965, Congress passed the national Water Quality Act.  Two years later, Texas created the Texas Water Quality Board consisting of members appointed by the governor.  The head of the board "sided with rural interests and prevented urban interests from establishing pumping limits, as a supposed conservation measure (Donahue, 1998)."

The first initiative for preserving water quality from a group of citizens opposed to development over the recharge zone.  Developers, led by former governor John Conally, proposed the construction of Ranch Town, a large suburban development over the aquifer's recharge zone designed to house 88,000 people.  Opponents led by an urban planner at a local private university and a family with banking interests on the south side of San Antonio began to warn citizens that the development would threaten water quality (Donahue, 1998).

Then in 1973, the La Quinta chief executive officer Sam Bishop proposed construction of the Southwest's largest mall of the aquifer recharge zone.  Citizens for a Better Environment (the same citizens who fought Conally, now organized) joined with Citizens Organized for Public Service (COPS) and brought up the issue of a moratorium on development over the aquifer to a public vote.  The public voted in favor of the moratorium and the developers sued.  The vote was overturned by Texas Supreme Court because the Texas Constitution does not allow the overturning of a city council zoning decision by referendum (Donahue, 1998). 

A new group of citizens, the Aquifer Protection Association (APA) collected signatures for county commissioners and city council to purchase for the public trust 6-8 thousand hectares over the aquifer recharge zone in order to prevent further development.  The developer-controlled city council rejects the petition.  However, in 1974 Congressman Henry B. Gonzalez was able to amend the Safe Drinking Water Act, which propitiated federal assistance to any project that might pollute urban groundwater supplies (Donahue, 1998).

By 1970s it is clear to developers that if growth of city to north continues over the recharge zone an alternative to the Edwards Aquifer as the city's sole water supply had to be found.  Mayor Henry Cisneros strongly promoted a city council vote on July 19, 1979 to approve the three-part water management plan that included conservation, recycling, and the construction of a surface water reservoir called Applewhite.  Opponents feared that construction of the reservoir would eventually lead to increased development over the recharge zone.  Others saw the reservoir as a way to increase taxes and provide construction firms and land developers with work.  Opponents argued for a management plan for the aquifer that could satisfy the region's water needs without the expensive alternative sources (Donahue, 1998).

When presented with the petition to stop construction of Applewhite, the city council placed the proposition to stop construction of the Applewhite Reservoir on the ballot of a citywide election to be held on May 4, 1991. However, construction continued anyway and the city Water Board awarded a $37.5 million contract to a local contractor to complete the reservoir and create a plant to treat surface water (Donahue, 1998).

In April of 1991, the Guadalupe-Blanco River Authority (GBRA) announced that a lawsuit would be filed under the Endangered Species Act.  The GBRA represents economic interests of Hays and Comal Counties.  Springs that feed the Comal and Guadalupe Rivers are major tourist attractions and the water from the springs sold to downstream industrial users is an important source of income for the GBRA.  Also, the springs house many endangered species.  In the meantime, Mayor Lila Cockrell formed a political action committee called Water Now! because she feared federal imposed pumping limits (Donahue, 1998). 

The advice of Hans Helland and Carol Patterson of the Edwards Underground Water District swayed voters to vote down the Applewhite reservoir.  They advised that since the aquifer holds 31-68 billion cubic meters of water, it makes no sense to build a reservoir that holds only 50.2 million cubic meters, much of which would evaporate in the Texas sun.  Instead, a better alternative would be to build recharge dams to ensure that more runoff returned to the aquifer. Construction on the Applewhite reservoir ceased (Donahue, 1998).

On May 19, 1991 a lawsuit was filed by the Lone Star chapter of the Sierra Club and the GBRA in Midland Texas alleging that the Secretary of the Interior and USFWS failed to protect endangered species dependent on the Aquifer.  On the 13th of August, 1994 voters reject Applewhite a second time by greater margin (Donahue, 1998, Votteler, 1998).

In February of 1992 TWC presented a plan for the state to manage the Edwards and other aquifer and called for mandatory cutbacks when the aquifer drops to certain levels.  The city of SA objected to the TWC's plan contending that downstream users would pay nothing yet reap the benefits of the city's conservation efforts.  Hence, the city called for a feasibility study of augmentation of the springs in Comal and Hay counties in the hopes of avoiding pumping limits.  However, augmentation was deemed infeasible because pumping water from greater depths of the aquifer into these springs would change both the chemistry and temperature of the springs that the endangered species depend on for survival (Donahue, 1998).

On April 16, 1992, the TWC declared that the aquifer was really an underground river.  TWC changed the name of the aquifer to the Edwards Underground River, which would then according to Texas law, be under the TWC's control.  However, State District Judge Pete Lowry of Austin found that the aquifer was not an underground river as the TWC had claimed and thus the TWC did not have the authority to take it over (Donahue, 1998, Votteler, 1998).

On January 30, 1993 Judge Bunton ruled in favor of the Sierra Club and GBRA and urged the Texas legislature to reduce pumping from the Aquifer in times of drought by at least 60% to ensure the survival of endangered fish, salamanders, and plants by the 31 of May 1993.    The Legislature was given until May 31, 1993 to enact a regulatory plan.  If the legislature had failed to accomplish this, the plaintiffs could seek regulation by USFWS.  The state legislature considered three bills, then made a compromise on them: the elected Edwards Underground Water District would be replaced by an appointed board called the Edwards Aquifer Authority (EAA).  A larger advisory committee would bring together the various river authorities and downstream industrial users.  The authority would install meters and be responsible for monitoring and protecting water quality.  This bill (Senate Bill 1477) was passed on May 30, 1993 (Donahue, 1998, Votteler, 1998).

When the bill is fully implemented, the EAA must enforce pumping limits of 450,000 acre-feet before December 31, 2007, and 400,000 acre-feet after that, unless drought conditions require more severe restrictions.  "The EAA shall ensure that the continuous minimum springflows of the Comal Springs and the San Marcos Springs are maintained to protect endangered and threatened species to the extent required by federal law (Votteler, 1998)."

The Justice Department ruled that the state plan to replace the elected board with an appointed one violated Section 5 of the Voting Rights Act. Also, Medina County Underground Water Conservation District argued that the regulation of groundwater was a violation of private property rights and that the S.B.1477 must be declared unconstitutional because no other water regulations existed in Texas.  Later Judge Bunton called S.B. 1477 dead and declared that new legislation would be needed to meet the Justice Department's demand.  A week after this ruling mayor Nelson Wolff of SA named a twenty-six member citizen committee to study city water needs through the year 2050 and, since the city would face pumping limits, to suggest new sources of water including the Applewhite reservoir.  This committee represents a range of city power brokers and notably absent were opponents to the Applewhite Reservoir and vocal supporters of aquifer recharge and spring augmentation (Donahue, 1998, Votteler, 1998).

In the summer of 1994 the Sierra Club requested from the district court that a monitor be appointed for the case and prepare an emergency plan to reduce pumping from the aquifer due to extreme decreases in Comal Springs flow.  The Emergency Withdrawal Reduction Plan for the aquifer was researched and developed in thirty days.  It provided for staged reductions of pumping for municipal, industrial, and agricultural uses of groundwater.  The plan was developed in order to maintain flow at Comal Springs above the 200 cubic feet per second jeopardy level for fountain darters, established by the USFWS.  However, it rained in the fall, and although the need for such an emergency plan did not dissipate, the immediate political impetus for the creation of one did (S4, Votteler, 1998). 

In May the 2050 Water Committee presented its report (2050 Water Plan, for a summary of the water plan see appendix), which recommended the Applewhite Reservoir to the city council.  As described by its proponents, Applewhite would hold water only for discharge downstream, not for drinking.  The water discharged downstream, via a diversion canal to petrochemical users in the Victoria area, would be exchanged for aquifer water captured form the Guadalupe River, stored in Canyon Lake, and brought via pipeline to SA.  The total cost was estimated to $300 million, including $76 million to complete the Applewhite Reservoir, $21.5 million for the diversion canal to deliver Applewhite water traded to petrochemical plants, $32 million of the Canyon Lake pipeline and $130 million of the treatment plant to purify Guadalupe River water, and also called for monies to enhance conservation measures, construction of recharge dams over the aquifer "if feasible" and reuse of wastewater for non-drinking purposes on local military bases and golf courses (Donahue, 1998).

Opponents on and off the council quickly noted that there were other alternatives to Applewhite and the rest of the 2050 Plan that would be more efficient and cost-effective than building an expensive surface water system and ultimately, critics argued that the building of Applewhite would do nothing to address the springflow problem. Also, the opponents suggested augmentation, the pumping of aquifer water into the springs.  This possibility was dismissed by Applewhite supporters even though there seemed to be ample water in the aquifer to augment the springs in time of drought without the need to limit pumping across the entire region (University of Texas Bureau of Economic Geology revealed that the total storage of the aquifer was 265 billion cubic meters, four times what the U.S. Geological Survey had estimated in 1978).  Opponents of augmentation suggested that the quality of water changes with the depth of the aquifer.  The water lying deep in the aquifer is too cold to sustain the endangered species of the springs (Donahue, 1998).

Two weeks before election the pro-Applewhite forces drew from a $700,000 budget  to buy television time to promote the 2050 Water Plan.  Their funding was provided by local businesses, including several construction and contracting firms.  Opponents disputed the plan price tag for the project and predicted that construction of the reservoirs and pipelines could cost residents more than $7 billion in bonds and increased water rates (Donahue, 1998).

In July of 1994, the University of Texas engineering study on augmentation of the Comal and San Marcos Springs was released.  The study indicated that augmentation was feasible.  Opponents of the Applewhite Reservoir demonstrated on steps of City Hall to argue that augmentation was viable, cheaper alternative the Applewhite.  Also, 22 geologists, hydrologists, engineers, and academics attached their names to a prepared press release stating that the Applewhite site had "major technical flaws and problems" from a scientific point of view.  Finally, on August 13 1994, voters turned down Applewhite by a greater majority than in the first referendum in 1991 (Donahue, 1998).

Since no supplemental water source was available to reduce San Antonio's dependence on the aquifer, the court Monitor suggested that the city and other pumpers apply for an ESA section 10 (a) Incidental Take Permit (ITP).  The ITP would allow the inadvertent taking of federally listed species during an otherwise legal activity.  This permit requires a Habitat Conservation Plan.  The development of the HCP was used to secure a twenty-year permit allowing inadvertent takes.  Permit holders were expected to implement the plan.  Under the ITP, the take and jeopardy levels of springflows fell from 200 to 150 cubic feet per second and 150 to 60 cubic feet per second (for short durations) respectively.  The difference between these jeopardy flows is 90 cubic feet per second, which has been estimated to allow additional pumping of approximately 65,000 acre-feet per year in dry years for those who rely on withdrawals form the aquifer.  Judge Bunton created the Incidental Take Permit Panel to review and discuss the available water supply and conservation options to preserve the endangered species.  Information collected at panel meetings was used as the foundation of the HCP (Donahue, 1998, Votteler, 1998).

In June 1995 HCP was released.  The plan included themes of conservation and reuse of existing water supplies, and the introduction of 250,000 to 350,000 acre-feet of additional water supplies to substitute for withdrawals form the aquifer.  Some alternatives were proposed to protect the species, and assure minimum flows in the springs during droughts (Votteler, 1998).

In March of the same year the Revised Emergency Withdrawal Reduction Plan was produced for the court from information collected during Panel meetings.  This plan was produced in anticipation of decreased springflows for that year.  However, Judge Bunton chose to appoint lawyers representing various interests in water policy to develop recommendations for maintaining springflow above the 150 cubic feet per second jeopardy level at Comal Springs.  The Lawyer's Panel Plan was created.  However, it rained again, and again, water conservation was avoided (Votteler, 1998).

In May of 1995, Governor George Bush approved the changes to S.B. 1477 to give EAA an elected board to satisfy the concerns of the court.  Later this was again deemed unconstitutional due to violation of private property rights.  However, the State successfully argued that the power to create entities to regulate the groundwater is an established fact in Texas law.  Alas, the Texas Supreme Court deemed S.B.1477 constitutional (Votteler, 1998).

Finally in February of 1996, the Sierra Club vs. Secretary of Interior case was resolved after the USFWS published a recovery plan for the threatened and endangered species at Comal and San Marcos Springs resulting in the end to the rule of free capture for the Edwards Aquifer and the creation of a state entity specifically designed to regulate pumping (Votteler, 1998). 

In April of 1995 the Sierra Club filed another lawsuit.  This time it was against the U.S. Department of Agriculture alleging that the USDA allowed agricultural activities to harm species.  In July of 1996 Bunton ruled in favor of the Sierra Club.  The USDA was ordered to develop and implement a program to protect water quality and to preserve natural resources and protect fish and wildlife through land conservation (Votteler, 1998).

Then again in May 1996 the Sierra Club filed a lawsuit concerning the preservation of the endangered species.  The lawsuit was against the city of San Antonio.  Pumpers of the aquifer (including over a thousand individuals, organizations, and corporations) were charged with causing takes of endangered species.  This occurred in a time of drought.  In July, both springs were well below jeopardy levels and there was a possibility of total cessation of flows at Comal Springs.  However, the EAA did not declare a water emergency.  Instead, Judge Bunton ruled that the Monitor produce a draft of a regional plan to reduce pumping from the aquifer.  The plan was developed within the ten-day deadline and then revised and adopted by Bunton as the 1996 Emergency Withdrawal Reduction Plan for the Edwards Aquifer.  This plan contained a schedule of staged reductions of municipal pumping of discretionary water use from the aquifer.  This plan was activated on August 23, 1996 (Votteler, 1998).  For an outline of this plan see appendix 2.

Ironically, on August 23, 1996 it San Antonio experienced heavy rains.  Then on April 30, 1997 Bunton's ruling was vacated due to the rains and also because the EAA could have handled the situation (Votteler, 1998).

The next cycle began in 1998.  The USFWS threatened to bring criminal charges against pumpers in order to protect the species in danger of dying from diminished springflow.  In response to the drought, EAA implemented the USFWS's Critical Period Management Plan, which restricted certain uses of water.  However, this plan was later invalidated because improperly adopted.  Also, the EAA sought a permit from the State for a $500,000 cloud-seeding program to increase rain in selected areas.  Around this time, the flow of Comal Springs did in fact drop below take levels.  USFWS did not file charges against pumpers.  August rainfall again raised springflow significantly above take levels (Votteler, 1998).

Travis County issued a temporary injunction against the EAA that same August disputing the rules that relate to the processing of permit applications.  The EAA notified permit applicants on April 29, 1998 that it was proposing to approve permits for withdrawals form the aquifer totaling 484,600 acre-feet after receiving applications for 852.800 acre-feet.  The EAA was to begin enforcing the new 484,600 pumping cap by January 1, 2000 (Votteler, 1998).

In December of 1998 the San Antonio Water System board of trustees gave preliminary approval for the purchase of a large amount of groundwater form the Aluminum Company of America.  About 50%, or 90,000 acre-feet of SAWS's current pumping from the aquifer could be transferred annually from the Aluminum Company operation northeast of Austin by piping it to San Antonio through the recharge zone.  Alternatively, it could be traded in exchange for allowing SAWS to receive  additional commitments of water form the Guadalupe River.  A pipeline could potentially be adapted to serve as a conveyance facility for future transfers of additional ground and surface water from the east to San Antonio (Votteler, 1998).

In January of 1999, the annual legal limit on pumping was 792,000 acre-feet.  This amount is 250,000 acre-feet above the record year of pumping in 1989.  In addition, no regional drought management plan was in place (Votteler, 1998).

Finally, on April 27th 2000 an article appeared on the cover of the San Antonio Express News discussing a new drought management plan and also a management plan to be enacted in times of a water emergency.  The EAA is drawing up a long-term drought plan and stands ready to adopt an emergency plan when the aquifer level falls to 650 feet.  The three-stage drought plan requires aquifer pumping cutbacks of 5% in stage I, 10% for stage II, and 15% for stage III.  The plan will include cutbacks on waters used for landscaping.  Also, landscape watering will be restricted to certain times.  For more specific details on these pumping restrictions see appendix 3 (Needham, 200).

C.                 Possible means of ensuring springflow

            The foremost hazard to the critical habitat in the San Marcos and Comal Rivers is a lack of water.  The Comal springs went dry for nearly five months (144 days) in 1956 and the San Marcos came very close, dropping to only 45.5 cubic feet per second (Eckhardt).  The Edwards aquifer is currently solely dependent on rainfall for its recharge, which means in times of drought the water table falls.  Problems occur when the water table falls below the level of the springs and the springs go dry.  In a natural setting a drought long enough to cause both springs to go dry would be very rare, in fact the San Marcos springs have never gone dry as long as humans in the area have kept records.  The hazards are all human based and occur because this area is no longer in its ”natural” state.  Because of this, the solutions must also be human based.

            Besides natural springflow, there are several other sources discharging water out of the aquifer.  Humans use the water for municipal purposes such as drinking, showering, and washing, for agricultural and lawn irrigation, for commercial processes such as beer making and power plant coolant, and for tourism and recreational purposes.  The water pulled out by humans is water not available for natural springflow.  Here is the problem: humans have used the aquifer throughout human inhabitation, but now our pumping activities could jeopardize the endangered animals that depend on its springflow. There are several man made solutions to our man made problems, and one of the most important solutions is through water conservation.

The Edwards Aquifer Authority began operation on June 28, 1996 with the mission to manage and protect the Edwards Aquifer system, and with a mandate to limit withdrawals.  They are the organization with “powers, rights, and privileges necessary to manage, conserve, preserve, and protect the aquifer”  (EAA Act article 1 section 1.08, 1999).  They have authority over eight of the counties that lie over the Edwards Aquifer recharge and artesian zones; Atascosa, Bexar, Caldwell, Comal, Guadalupe, Hays, Medina, and Uvalde (EAA Act article 1 section 1.02, 1999).  The EAA Act does not list some counties; therefore, the EAA does not have authority over Edwards, Real, Kerr, Bandera, or Kendall counties, even though they are located over the drainage area of the aquifer system. Kinney County is also not governed by the EAA even though more than a quarter of the county lies over the aquifer system.  All of the county to the north and east of Brackettville lie on either the artesian zone, recharge zone or the drainage zone.  One would expect the EAA to have authority over that part of the county similar to the way that they only have authority over parts of Comal, Caldwell, Hays, Guadalupe, and Atascosa counties.  The reason this might prove important is that a long section of the West Nueces River flows through Kinney county section of the recharge zone. (EUWD, Water Resources of the Edwards Aquifer Region map).

            The first and most obvious solution lies in conservation.  The human animal needs to drink less than one gallon of water per day to survive, but in today’s culture we consume on average 176 times that personally for all uses including drinking  (Bock, 1990).  This figure doesn’t include the water used to grow the food we eat, the water used in manufacturing the things we use every day, or the water we use to irrigate our lawns.  The differences between the amount we use and the amount we need represents a significant portion of water and therefore educating people about how to conserve water could reduce overall consumption dramatically.  Resource planners estimate that easy common sense conservation efforts can reduce water use by at least 10% to 15% (EUWD pamphlet 1992).

Both E.A.A. and San Antonio Water System are supplying money and personnel to an education program that shows people how they can conserve water and save money too.  The Edwards Aquifer Authority tells the public ways in which water can be conserved and why the water is so important in this region.  S.A.W.S. goes beyond educational means and offers the public incentives to reduce their water use.  S.A.W.S. offers a refund up to 500 dollars for installing a qualifying Watersaver Landscape using drought tolerant plants rather than St. Augustine grass, (EUWD, Xeriscape) a percentage discount for purchasing low flow toilets, free water saving devices like toilet dams, low-flow shower heads, free leak detection, and information packets with much more detailed information on how to conserve water (SAWS water saver).

Education alone is typically not enough to significantly reduce water usage.  To “encourage” users to be more conservative, other more direct measures must be taken.  Two such measures are pumping limits and a higher price for water.  The E.A.A. has the authority by statute to issue pumping permits and therefore limiting the amount of total water being pumped.  The water pumping permits are given out according to several factors such as historical use, level of beneficial use and proportional adjustment factors.  With these pumping limits in place and with the aid of meters in place on all Edwards’ wells, the Edwards Aquifer Authority can make sure the pumping does not exceed the pumping limits put in place by the E.A.A. act.  To reduce the consumption of water throughout metropolitan areas, one solution would be to raise the price of the water.  Right now San Antonio has one of the lowest water prices in the state, which means that it does not cost much to waste water.  The April 2000 water bill for San Antonio Water System users shows that the cost for residential water use is 72.2 cents per thousand gallons (authors water bill).  The average price for water in the United States is $1.30 for every thousand gallons (Bock p.14). This shows that San Antonio’s water rate is almost half of the U.S. average. The higher prices will cause people to try and save money and therefore water too.

Another method to reduce the water pulled from the aquifer is to recycle it.  Sewage treatment plants are used around the world to treat sewage to a point at which the water can be released into surrounding watersheds.  The treated water is usually clean enough to be discharged into lakes, rivers, and streams, without causing a dramatic change in water quality.  This water is often used by down stream users.  In other places around the world, they take this even further.  In Germany, for example, the waste water is treated and purified to a level at which it is re-introduced into the public water system for all uses, including drinking (Interview with Sabine Thomas, March 2000).  San Antonio doesn’t want to go that far, but San Antonio is willing to use the treated water for other uses such as irrigation and industrial purposes.  Mitchell Lake was an oxidation pond for San Antonio’s sewage until the first treatment plant was constructed. Braunig Lake constructed in 1963 and Calavaras Lake constructed in 1968 are both cooling lakes for San Antonio’s electrical power plants.  All three lakes currently receive water from the San Antonio sewage plants. 

There are four water recycling centers in San Antonio; Leon creek WRC, Dos Rios WRC, Medio Creek WRC, and Salado Creek WRC.  The Dos Rios Treatment facility produces the most treated water, about 60 million gallons of effluent per day.  A majority of this water is places into the creeks by which they are named and eventually make it to the San Antonio River system.  These plants have recently started to pump their treated water out to some non-potable water users.  Trinity University and several other large water users have taken part in the city’s water recycling program (Purple Pipe Program).  This water is used to water lawns, trees, and often golf courses (Eckhardt).  The amount of treated water that is used is theoretically water that no longer needs to be drawn directly from the aquifer.  The Purple Pipe Program is not inexpensive to set up nor maintain, but nearly all of the options that actively conserve aquifer water are more expensive than direct withdrawal from the aquifer.  The costs to the users however, must remain the same as the normal water or none would take part in the program.  The program is still in the beginning stages, but there are plans to expand in order to reach new users Eventually, the SAWS recycled water program will supply non-potable water for beneficial use at 20% of the volume that San Antonio currently withdraws from the aquifer annually (http://www.edwardsaquifer.net/reusehtml). 

            Another obvious solution is to increase the amount of water in the aquifer.  This can be accomplished in several ways.  One of the most productive ways to increase the water recharged into the aquifer is through the construction of recharge dams.  Title 31 of Texas Administrative Code Chapter 711 under ground water withdrawal allows for recharge under the following methods. 

First, injection of source water directly into the confined or recharge zone of the aquifer through aquifer storage injection wells, as defined in section 713.1 of this title.  Second, infiltration from the surface into and through the unsaturated zone to the water table portion of the aquifer through the impoundment of source water behind a dam in a reservoir located on a watercourse in the recharge zone of the aquifer.  Lastly, any other artificial method determined by order of the board to recharge the aquifer consistent with the Act or this subchapter.


            Four of these structures have been constructed in the late 1970s and early 1980s and have proven to be very effective on a small scale.  The Seco Creek Dam (1982) provides the most annual recharge at 2960 acre-feet.  This is in part due to a 10-foot wide and 15-foot deep Diversion channel extending 685 feet from the main stream to a large 50-foot diameter sinkhole.  Seco creek structure recharged 13,000 acre-feet in 1987.  The Parker Creek Dam (1974) averages 519 acre-feet and is the oldest of the four structures.  Middle Verde Creek Dam (1978) has average annual recharge of 904 acre-feet and the San Geronimo Creek Dam (1979) recharges 744 acre-feet annually (EUWD, annual report 1993 to 1994).  These structures are built on typically dry creeks and only temporarily capture flood waters and hold them over the recharge zone so the water is allowed more time to percolate through cracks and seep into the aquifer. 

            This form of recharge enhancement has been known for years, but has not always been considered a reasonable solution.  It is gaining strength again with recent rules in the Texas Administrative Code on ground water withdrawals.  This new legislation allows for the parties involved in construction of recharge structures on approved sites to have credit for the water recharged from their facility.  This is a much less expensive method to obtain extra water because the users do not have to transport the water they collect; the aquifer does that.  The conditions for suitable sites are quite selective, and for good reason.  The sites must meet all water quality standards for the life of the project, which includes surface development activity proximate to point of recharge, and over the place of storage.  There are twenty such criteria for aquifer recharge and storage permits to ensure water of the highest quality (TAC chapter 711.228).

Recharge to Edwards Aquifer is derived mainly from streams that cross the outcrop of the Balcones escarpment.  Some is derived form direct infiltration of precipitation on the outcrop (EUWD Bulletin 42, March 1985).  Recharge structures increase recharge if constructed over this area.  Type I “catch and release” structures occur above the outcrop and have recharge release rates generally specified for reservoirs located upstream of recharge zone and equal to threshold rate at which Edwards Aquifer will accept recharge from the streambed crossing the outcrop.  Direct recharge comes from Type II structures where percolation occurs through the bottom of the reservoir and enter the aquifer through the unsaturated zone (TAC chapter 711.270).  These structures can also have a diversion rate for direct or indirect injection to Edwards in adjacent watershed or directly through a sinkhole as at Seco Creek Dam.  Type II structures are located over recharge structures and the entire volume of water usually drains within one month.  Soil Conservation Service Flood Retardation Structures (SCS/FRS) recharge 70-100% of stored water with little losses due to evaporation (HDR Engineering, Inc. 1993).  Some possible recharge sites are SCS/FRS at Leon, Helotes, and Government Creek watersheds (similar to Salado Creek watershed), Cibolo Dam number 1 on Cibolo Creek near Selma, one additional SCS/FRS in dry Comal Creek watershed, the Lower Blanco River project on Blanco River near Kyle and Coptin Crossing Type I recharge.  The Lower Blanco River Project is the largest in structural program, with a maximum storage of 35,230 acre-feet.  It was large enough that evaporation was taken into account when figuring recharge.  With these 4 structures, the Guadalupe-San Antonio River Basin recharge enhancement would total approximately an additional 123,060 acre-feet per year (HDR Engineering, Inc. June 1994).

Headwaters of Nueces River Basin contribute about 51% of total volumes of surface water recharged to the San Antonio portion of Edwards Aquifer (HDR Engineering, Inc. 1993).  Storms cause creek levels to rise well above natural recharge rates.  Therefore recharge dams would capture and recharge these floodwaters.  The Nueces River Authority, city of Corpus Christi, and South Texas Water Authority sponsored the studies due to the possible effects on “their water”.  The study was undertaken to in part evaluate the potential enhancement of aquifer recharge and the impact to other users of Nueces River Basin studies began spring 1990.  Findings indicated, “a significant potential exists for enhancing recharge through construction of dams on major streams crossing the recharge zone.”  Six projects were suggested when Phase III was completed in late 1991.  All of these projects would include dams located near the downstream boundary of the recharge zone.  Listed from East to West: lower Verde, lower Hondo, lower Sabinal, lower Frio, lower Dry Frio, and Indian Creek projects.  No fatal geologic, geotechnical, or environmental flaws are believed to exist at these project sites.

Lower Verde, lower Hondo, lower Sabinal, and lower Frio were (1994) to be moved to permitting phase.  The lower Sabinal project has the lowest unit cost of recharge enhancement capacity of 8,750 acre-feet yearly at optimum size (see Table ES-1a).  Recommended recharge enhancement program is comprised of Lower Verde, Hondo, Sabinal, and Frio projects each constructed at optimum size.  Increase natural recharge 14% for average rainfall and 6% during drought.  The program would provide 45,135 acre-feet a year at $142 per acre-foot ($0.44 per 1,000 gallons).  Under drought conditions 9,250 acre-feet per year at $692 per acre-feet per year ($2.12 for every 1000 gallons).  With Indian Creek project, recharge increases to 23% under average and 18% in drought conditions (1947-1956).

The Indian Creek project is not suggested for the permitting stage, because downstream water would be affected.  Choke Canyon and Lake Corpus Christi would receive an inflow reduction of 0.1-0.7% based on operating policy of reservoir system which equals 170-1,229 acre-feet/year.  Nueces Estuary average annual inflow would reduce by 0.1-0.5%, which equals 728-2,594 acre-feet/year.  The estimated cumulative impact on inflow is about 7,022 acre-feet per year or 1.4%.  These percentages are small, but they are enough to have the plan delayed (HDR Engineering, Inc. June 1994).

Without getting too deeply rooted in the geology of the aquifer, there is a bottleneck type formation near Uvalde.  The Kinippa Gap formation slows water and to the west of the formation the water level is significantly higher and more stable.  To the East the water level is lower and more fluctuating.  The gap also creates a significant lag time of about 2 years between water recharged on the west and when it passes the gap and can be withdrawn in the east.  This time lag can be used to humans advantage.  If Water is added to the aquifer west of the gap, it takes 2 to 4 years to reach the springs.  This puts a 2 to 4 year delay between large rains and large springflow rates.  This is good news for the springs in the first few years of a drought.  This lag time feature could be enhanced even further if a pipe carried water from surface water east of the gap and transported it to a recharge structure west of the gap.  The pipeline would be expensive, but it makes good sense.  If for example the springflow exceeded its average output, you could collect the extra water just before it entered the Guadalupe River system and not affect down stream water rights.  If this surplus water was shipped to a recharge structure west of the Kinippa Gap, it would essentially provide recharge in times of plenty, and this would be discharged in 2 to 4 years.  The pipeline would probably cost around the same as the one proposed to bring water to San Antonio from ALCOA, about 450 million dollars (Express News March 18,2000).  There would be a further benefit if the pipeline were designed to be two ways.  This could allow for water to be shipped from a well west of the gap back down to an injection site near the springs.  Since the springs will go dry again even under minimum withdrawals, this could be used as a way to keep the springs running.  At the injection site, there would be the opposite of a cone of depression (a pyramid of water) that may raise the water table enough to keep the springs flowing at or near the minimum levels to avoid take.  This Idea is very new (so new that my source didn’t want to be quoted on this topic), and still needs a lot of research as to the viability of several aspects of this potential option. 

The Edwards Aquifer authority has also adopted a controversial plan to increase recharge.  Since 1998, they have received a permit from TNRCC and have been paying for precipitation enhancement commonly referred to as cloud seeding.  The cost is about 4 cents an acre and it is estimated that rainfall is increased 10-20% above normal.  The total project costs are $500,000 and it is carried out by Weather Modification, Inc. The target area is about 6 million acres.  This could theoretically increase recharge by the same percentage as rainfall increase. (EAA, unaudited first quarter financial statements March 2000)

            To provide water to the springs even when the level of the aquifer fell; a method of augmentation could be implemented.  All of the initial tests on springflows suggested that springflow augmentation was necessary to ensure the flow of the springs with another long-term drought.  According to the Texas Water Resources Institute, there is no proposed water plan (as of 1993) that predicted Comal Springs would flow with a repeat of the 1950s drought.  With this information, it seems dangerous to leave the springs without a back up, when we know they will go dry again. 

Springflow augmentation is a way to allow the water to flow from the springs, even if the aquifer levels temporarily drop below the levels at which the springs would naturally stop flowing.  This is accomplished by pumping water from a lower aquifer depth and placing it at or near the point of natural springflow.  In San Marcos, the ranges in total dissolved solids were 8,800-10,500 mg/L.  The specific conductivity values were between 14,000 and 16,405 ms/cm.  Thus, the characteristics of the water did not vary significantly from well to well, nor did it vary vertically within a particular well (Poteet, Collier, and Maclay. P.1-17).  This suggests that augmentation of the San Marcos Springs would not change the characteristics of the spring water and therefore the artificial supplementation could provide some level of protection for the endangered species during times of drought (McKinney and Sharp, 1995).

For New Braunfels, specific conductance values ranged from 498 to 4,190 ms/cm (290-3,640 mg/L).  The specific conductance varied from high values at the bottom of the test wells to low values at the top.  The highest values were found in the A-1 well furthest form the fresh water zone.  The C-1 well had the lowest specific conductance values between 578 and 1,850 ms/cm.  This test well may have lower specific conductance because it is closest to the fresh water zone (Poteet, Collier, and Maclay. P.1-17).  The water quality near Comal Springs varies both vertically and geographically and therefore may not be suitable for springflow augmentation, but a site specific study could show otherwise.

            The results of the EUWD study also show that the specific conductance is several orders of magnitude greater at San Marcos than near New Braunfels.  This may account for differences in springflow and show why Comal Springs went dry while San Marcos springs did not.  It also shows that San Marcos has much higher dissolved solids.  These elevated levels of dissolved solids are not seen in the natural springflow at San Marcos. Another difference is that the temperature at both sites varied slightly from 25.0°C to 27.5°C, while at the springs the water temperatures are 23.3°C at Comal Springs and 22°C at upper San Marcos (USFWS p.9).        These discrepancies may suggest that the project’s results do not directly correlate to natural springflow.  The performing of these tests requires several wells to be drilled into the aquifer so even obtaining this data may potentially disrupt the aquifer and the nearby springs.  It is a touchy topic that needs further research before conclusive results can be drawn on a site-by-site basis.

            The ability for these endangered species to live under these man-altered conditions is evident in two ways.  The first is that most of these species have been kept and bred in captivity under totally artificial conditions.  The second condition occurred in 1956 when the Comal Springs went dry.  The San Marcos Springs were still flowing under reduced rates, but were receiving supplemental water from a man-made water well from Spring Lake area.  This supplemental augmentation may have added just enough water to keep these species alive and therefore their existence may already be due to a form of springflow augmentation.

            There is another form of augmentation that has been discussed.  This form of augmentation is really a form of water recycling where water from downstream is collected and pumped back upstream to the spring site to allow for greater flow.  This method is not as good as the first because it does change the water.  The water from the Edwards is pure, clean, pollution-free, and thermally constant.  Water recycled from downstream has had time to warm up, collect pollutants, and collect sediments.  This recycled water may be altered to a point, which one or more of the endangered species cannot live in it.  The problem intensifies when the springs go dry and there is no cool spring water to feed the rivers.  The river is just recirculated until the springs return to normal.  If the springs again went dry for five months, the river water that would be recirculated for five months would heat up in the Texas sun and become too warm to sustain life if it had not entirely evaporated by then.  The recycle method of augmentation is much less desirable, but is included because it is still discussed in today’s literature.

            Surface water structures could be constructed as a supplemental water source.  Several of these surface water structures have been proposed, but they have all been rejected as sources for surface drinking water.  One highly publicized proposed structure was voted down twice.  Without getting into economics (yet), there are several inherent problems with the proposed reservoirs.  First, surface water is exposed to evaporation losses, which can become quite significant in hot Texas summers.  Secondly, all of the proposed surface water reservoirs are below San Antonio where the land is fairly flat and reservoirs would be large and shallow.  There are several environmental impacts occurring from large shallow lakes as compared to deeper ones, including higher surface area to volume ratios, which increase evaporation and temperature fluctuation.  The flat terrain also means that more land has to be flooded for an equivalent amount of water. On top of being shallow and evaporating, the water would have to be pumped up-hill to the treatment plant.

            Surface water reservoirs are not all bad however.  The bad part is that none of the good ones are being proposed.  The environmental impacts of daming rivers and evaporation losses cannot be avoided, but with proper placement, they can be lessened.  One example is Median Lake to the Northwest of San Antonio.  It is up-hill from San Antonio, so water would not have to be pumped to a treatment plant.  It is deeper so the surface area to volume ratio is less and therefore less evaporation.  The greatest benefit is because of placement.  Some parts of Medina Lake fall over the recharge zone and therefore have provided an extra 40,000 acre-feet of annual recharge since 1912 when it was constructed.  A structure such as this is not only a potential source for surface waters, but because of placement, it also acts as a recharge structure and provides the equivalent of about 10% of current aquifer water usage.  In November 1999, BMA (Bexar-Medina-Atascosa Counties Water Control and Improvement District 1) approved a contract with Bexar Metropolitan Water District to supply 10,000 acre-feet annually from Medina Lake.  The water will be picked up downstream at a new surface water treatment plant opened in February 2000.  The costs to Bexar Metropolitan are $ 500,000 annually, and a 5 million dollar expansion project of Pearson Lake just below Medina.  Another surface water reservoir is Canyon Lake to the North of San Antonio.  Canyon is a large reservoir on the Guadalupe River, but it does not recharge the aquifer.  San Antonio had several chances to buy significant portions of water from the lake, but turned them down due to the higher costs when compared to the Edwards water.  Now all Canyon Lake water is fully committed to the Guadalupe River Basin. 

            Water users could buy water from other non-Edwards sources, or buy the water rights from an Edwards user who does not use all they are allowed to use.  These two methods both serve to lessen the total amount withdrawn from the Edwards.  The first scenario would be similar to a recently proposed project reviewed by SAWS (Express News. March 18, 2000).  San Antonio Water Systems is trying to decide if it makes sense to buy 55,000 acre-feet of water from a company East of Austin and pump it back more than 100 miles to San Antonio.  There are three options for the project.  First is 107 miles pipeline to bring spring water from the Simsboro vein of Carrizo Aquifer to a treatment plant to be built near downtown.  The second is 137 miles of pipe that would pick up an additional 40,000 acre-feet from a well in the Carrizo Aquifer.  The final option is similar to the first, but the pipeline would extend to small recharge dam over the recharge zone instead of going to a treatment plant.  High cost is the main drawback of this proposed plan (Express News March 18, 2000).  Others include the fact that water is being depleted from one area to feed a growing demand in another area.  Another problem is that ALCOA owns the lignite mine which water is pumped out of.  ALCOA is one of the top polluters in the state, producing more pollution than 1 million cars a day.  Doing business with such an environmentally destructive company indirectly condones environmentally destructive practices.

            A similar project is to pump water out of the Guadalupe River and up-hill a short distance to the source of a creek flowing into Medina Lake.  This would keep Medina Lake full more of the time and therefore increase annual recharge.  There is less information on this project, and the authors do not know what opposition is to this project.  A similar project is the contract between BMA and Bexar Met as mentioned above.  It takes farmers irrigation rights to the water, and sends the water downstream to Bexar Met users.  It is similar to the trading of water rights as discussed in the following paragraph, but involves surface water.  The problem with this plan is that it will provide surface water at the expense of water recharged by the full lake.

            The other method mentioned was the trading of water permits between Edwards users.  With governmental regulation coming fast, Edwards users are going to be given permits for the amount of water they can use based on several factors such as historical use and beneficial use.  Since users cannot pump more water than they are permitted to pump from the aquifer, they can try to purchase water from other sources, build recharge structures to get withdrawal credits, or purchase water-pumping rights from other Edwards users who are willing to use less water and get paid for their surplus.  Under this market approach to trading water rights, the sellers would not sell until they thought that they could get more money for the water than they could get by using it themselves.  The buyers would think along similar lines and this would lead the water to be used by the most efficient user.  Also, the market system would put a higher price on the water that is now limited in supply.  This pumping limit effectively put a cap on what had been seen as an unlimited resource, and put an end to the “Tragedy of the commons.”  This price would be a better representation of actual value than the suppressed value under the rule of free capture.   This would keep water use under the acceptable pumping limits, allow for some users to obtain more water, and reward those users who can get by with less water. 

II.  Mapping of the social processes

A.                  Participants, their demands, and their base values.

USFWS, Sierra Club, and GBRA demand that Comal and San Marcos springs flow above the take levels at all times.  Their strategy is to sue EAA for neglecting the ESA.  Their base value is conservation.  Pumpers (municipal, industrial, agricultural) demand adequate water for their persistence.  The base value here is the desire for an abundant supply of cheap water.  Their strategy is to defend their pumping as a right as a property owner as outlined in the Texas State Constitution.  Currently, the EAA demands cutbacks on pumping. 

B.                   The situation and how it effects the participants

The Edwards Aquifer has reached the point where the aquifer is unable to provide for the needs of all those dependent on it during dry years.  The aquifer can be visualized as a large bucket of water.  Comal and San Marcos Springs can be visualized as holes in the bucket towards the top of the bucket.  After the water level drops below the level of the holes in the bucket, there is still enough water in the bucket to satisfy pumpers.  However, the springs have run dry and biodiversity is lost, and Hays and Comal counties lose out on money earned by tourist attractions of Comal Springs and the Guadalupe River.  The loss of the biodiversity and money earned by tourism does not directly affect the pumpers.

More threats to the endangered species

In addition to decreased levels in springflow, another threat to endangered species survival is pollution.  There are also other hazards to the endangered species that are not tied directly to the aquifer and those will be discussed later.  All of the potential hazards must be addressed in order to achieve the goals of the 1996 U.S. Fish & Wildlife Ecosystem Recovery Plan.

            Pollution is a second issue of paramount importance to all the organisms that rely on Edwards’s water.  Regardless of water quantity, it would become unusable if it were to fall below a certain quality due to pollution.  Pollution can come from many sources including pesticide and fertilizer runoff, street runoff, gas stations and other forms of chemical storage.  The same structures that allow this aquifer such an exceptional recharge capacity also allow a direct conduit for pollution.  Again these problems occur as a direct result of modern humans. 

One of the main threats for pollution is through the development of the areas in the drainage and recharge areas.  This is simple because if there were no humans above the recharge and drainage zones, there would be no real threat of pollution.  In residential developments, pesticides and fertilizers are common, especially with commercial lawn care companies.  It is estimated that residential developments use 5-8 times as many fertilizers and pesticides than agricultural usage does.  Some suggestions to reduce run-off include vegetative buffers between developments and creeks (not on home owners lots), which would be maintained by SAWS.  These possible restrictions can be avoided with the competition of a water pollution abatement plan.  Water pollution abatement plans can be applied for by developers with unfriendly practices such as building subdivisions, strip malls, and golf courses.  EUWD did and now the EAA reviews the documents and sends them to Texas Water Commission.

  Other possible sources for pollution come from the transport of hazardous (even nuclear) waste on roads that cross the recharge and drainage areas, gas stations, EUWD suggests hazardous materials traps and vegetative channels along highways to catch some of the hydrocarbons, radiator fluids, and metal dust from brake linings.  Increased traffic increases risk of accidental spills of hazardous materials.  It also allows more access for commercial development activities such as gas stations, parking lots, and retail facilities.  Two known cases (1993) of leaking underground storage tanks resulted in localized contamination of aquifer and necessitated closure of private wells.  Events that would be hard to track back to the source are called non-point source pollution and are considered to be one of the greatest threats to our water system and the species of concern (EUWD Urban Development 1993 p.40). 

            Non-native invasive species play a major role in the survival of these endangered aquatic species.  Like many terrestrial or aquatic ecosystems around the world, the introduction of non-native species leads to a loss of bio-diversity in these Edwards springs.  Invasive species disrupt the natural balance that evolved over thousands of years, directly compete for food resources, alter the ecosystem directly or indirectly, or consume the native species.  Some harmful species that have invaded the springs are Tilapia, common carp, rock bass, sail fin mollies, Hydrilla, rams-horn snails, elephant ear, and nutria (USFWS p.21). 

            Hydrilla verticillata is a very hardy and extremely adaptive aquatic plant that has choked up rivers and lakes across Texas and surrounding states.  Its aggressive growth has overgrown much of the Texas wild rice (Zizania texana) habitat.  Colocasia esculenta has invaded the shorelines and out-competed native plants.  These huge elephant ear shaped leaves and tuberous roots change the shoreline habitat and may decrease suitability for the San Marcos Gambusia.

Marisa cornvarietis (giant rams-horn snails) graze on aquatic plants of the rivers.  When the snail population grown too large, which often occurs when flow rates fall, the aquatic plants are all eaten up.  This reduces or eliminates the cover vital for many species, including the fountain darter.  The snails are so harmful to the spring ecosystems that the springflow rates vary drastically with and without snails when defining flow to avoid take of these species.  In San Marcos springs for example, a minimum flow of 150 cfs is needed to avoid jeopardy, but if the snails were controlled, the flow rate would fall to 60 cfs.

            Myocaster coypus were imported from South America as a living aquatic lawnmower and have successfully invaded a number of waterways in Texas.  In the San Marcos and Comal Rivers, this common rodent often snacks on Texas wild rice.  With pressures from both plant (hydrilla) and animal (nutria and human) sources, it is no wonder large areas of Texas wild rice are being lost (USFWS p. 21).

            There are a number of other invasive fish that harm the endangered species.  The common carp, Tilapia, and sailfin mollies compete with fountain darter (and Gambusia?) for food and good habitat.  Other species such as the rock bass just feed on small aquatic animals regardless of their endangered status.

            One final group of invasive species is human beings.  Humans use the areas for recreational purposes, which often have a negative impact on the ecosystem.  Just walking on the bottoms disturbs the hiding places for the animals and the rooting medium for the Texas wild rice.  Some areas have been modified for recreational activities.  The shoreline may be modified into more of a smooth beach and vegetation may be removed to make the water more appealing.  Both of these habitat changes are harmful to the native species, while immediately beneficial to recreation.  Invasive species are not good for these ecosystems and humans are not helping the situation.

Now for a quick look at some of the economics of various plans.  To reduce water usage in the city, the water rate should be raised or heavily taxed.  A percentage rate increase across the board would not be the best solution.  A better solution would be a progressive price schedule.  This would allow light users to keep their low water bills, while charging higher prices per gallon to users who use more than a certain set amount.  There could be several levels of price increase to further discourage high water use.  If the water was taxed, the revenues acquired could be used for various projects such as, a water treatment plant, research on the endangered species, or feasibility studies of areas acceptable for recharge structures.  This would be one way to lower consumption.  Another way would to be set regulations that only allow lawn watering on certain days.

One of the least expensive options to get more water is through recharge structures so this section is on recharge economics.  While current value of an acre-foot of water is assessed at about $45.00 (in 1990), the estimated average cost of water artificially recharged by these structures over a 30-year period would be less than $15 per acre-foot.  These figures are calculated by taking the project costs, the Parker Creek, Verde Creek, San Geronimo Creek, and Seco Creek Dams cost a total of $ 1,879,494, and spreading that amount out over a certain number of years.  To stay consistent with other figures, we will use 30 years.  The average cost for the first 30 years would be approximately 62,650 per year. If the cost per year is divided by the amount of recharge (5127 acre-feet per year) the answer is the cost per acre-foot of recharge.   About $12.21 per acre-foot of recharge for the Four existing recharge structures.

 The EUWD has participated in the funding of other soil conservation service flood retardation structures.  The average recharge from these structures is about 13,000 acre-feet annually (The Water Source. March 1990).  Lower Verde, Hondo, Sabinal, and Frio projects each constructed at optimum size would increase natural recharge 14% for average rainfall and 6% during drought.  The program would provide 45,135 acre-feet a year at $142 per acre-foot ($0.44 per 1,000 gallons).  Under drought conditions 9,250 acre-feet per year at $692 per acre-feet per year ($2.12 for every 1000 gallons).  With Indian Creek project, recharge increases to 23% under average and 18% in drought conditions (1947-1956)(HDR Engineering, Inc. June 1994).  These SCS/FRS structures may at first seem expensive, but take a look at some of the other options.

For the SAWS arrangement with ALCOA, the water would carry a price tag of about 696 to 2,000 dollars per acre foot on top of the pipeline investment of 300 million to 457.2 million dollars (Express News March 18, 2000).  The transfer of Irrigation rights costs an average of $94 per acre-foot, but does not reduce pumping or increase recharge.  To purchase Medina Lake Irrigation rights for recharge enhancement would cost $159 per acre-foot.  To divert Guadalupe River water near Comfort to the Edwards Aquifer would cost about $ 2,079 per acre-foot.  To divert some flood flow of Canyon Lake to the recharge zone along Cibalo Creek would cost $10,471 per acre-foot (Comprehensive Water Management Plan p.2).  Although the 30-year lease of irrigation permits is the least expensive, it does nothing to help the springs situation.  The water market has come about since the EAA Act put a limit on pumping limits and ended the tragedy of the commons.  Trading water rights doesn’t decrease the total withdrawal, or increase the total amount of water in the aquifer, therefore the next least expensive Item, recharge Structures are the better option.

            The Edwards Aquifer Authority is also spending money in other realms not directly related to quantitative prices per acre-foot.  In March 2000, according to the Unaudited Finacial Statement, the EAA spent significant sums of money on the development of a Habitat Conservation plan, around 2 million dollars in the first quarter alone.  They spent $50,000 to help the Nature Conservancy purchase 3,057 acres on the Annandale Ranch in Uvalde County.  $30,722 was spent installing meters on Edwards Aquifer Wells.  $117,025 (approximately 1 quarter of the fixed costs) associated with the precipitation enhancement program.  Other money is spent on data collection.  For example, Chemron Incorporated is getting paid 7,000 dollars for the analysis related to a diesel spill.  All of these expenditures are important in gathering new information, which will help conservation efforts in the future due to a larger pool of data.  The money is in the same predicament as the water of the aquifer: There is just not enough to make everyone happy.




The fundamental reason for the conflicts over the aquifer lie in the different value system of the participants.  Each participant places a different value on water, and thus a different definition of water.  According to Donahue, “people endow water with cultural meanings, which are embedded in the institutional contexts within which people interact (Donahue, 1998).”  Therefore, water is a social construction as well as a physical resource.  The right of free capture of the aquifer's waters suited agricultural interests.  The Sierra Club envisioned water as an environment for endangered species only if pumping were limited even though it was not clearly established that such limits would ensure that the springs would continue flowing.  Homeowner-Taxpayer Association of Bexar County evaluated plans to manage water in terms of their financial impact on residential rates.  Other water activists defined the aquifer as a natural resource to be managed through increased recharge in times of abundant rainfall and increased drawdowns during times of drought.

Hydrological estimates of aquifer capacity tended to support the position that the scarcity was an artifact created by political and corporate interests whose objective was pipeline and reservoir construction at public expense.  Finally, some of the political elite characterized those who promoted management of the aquifer through augmentation as "radicals" who would "mine the aquifer" and jeopardize future growth and development in the city.

Meanwhile the elected Edwards Aquifer Authority is at work drafting plans to manage the aquifer that include licensing of all pumping from the aquifer and provision of compensation to some farmers in the western counties for not irrigating during the coming season.  Since governments in democratic societies ultimately have the responsibility of protection of the commons the state will be a major actor in managing such scarce resources as water.  Bureaucratic control becomes, then one cultural definition of water.  A solution to the issue of water management depends upon the ability of all major participants to debate the different definitions of water held by the participants and the construction of a common definition of water to be held by all participants.

            Management of endangered species in the Edwards Aquifer will continue to be complicated far into the future.  There are so many interested parties, many of whom have money and political clout, that there is no simple answer.  Thousands of people have spent millions of hours addressing this issue, and no one answer has emerged.  Rather, it has become apparent that continual dialogue and compromise will be necessary to manage the precious resource of the Edwards Aquifer.  Compromise will result from the interested parties realizing that everyone has a common vested interest in the conservation of the Edwards Aquifer.

There is promise for the future.  The most direct and effective approach is to conserve water.  If we pull less water out of the Aquifer, the springs will be less likely to stop flowing.  Beyond strict conservation of water, we have discussed many water management possibilities to manage for the endangered species.  Adding water to the Aquifer, possible through recharge dams, or even augmentation, are possibly feasible options, which will be debated far into the feature.  The Edwards Aquifer Authority is currently drafting a Habitat Conservation Plan, which will provide more structure in the conservation effort over the recharge zone.  Historically, water rights have been approached in a very anthropocentric fashion, only giving consideration to the water needs of the human population of San Antonio and surrounding areas.  However, a fundamental philosophical change is necessary; every organism has a fundamental right to a place on the planet.  It is self-serving to act otherwise.



Bock, Leslie.  The Story of Drinking Water. American Water Works Association, Denver. 1990.

Donahue, J.M.  1998 “Water Wars in South Texas:  Managing the Edwards Aquifer.”  Water, Culture, and Power:  Local Struggles in a Global Context.  Island Press:  Washington D.C

Eckhardt, G. A.  2000.  The Edwards Aquifer Home Page.  www.edwardsaquifer.net. 

Edwards Aquifer Authority.  1996.  The Edwards Aquifer: A Texas Treasure.  San Antonio, TX.

Edwards Aquifer Authority Act, 1999 Texas General Laws (as found on http://www.e-aquifer.com/SALLY/STATUTE.html)

Edwards Underground Water District.  Water Resources of the Edwards Aquifer Region.  San Antonio, TX.

Edwards Underground Water District. Water Resources of the Edwards Aquifer Region Map.  No Date.

Edwards Underground Water District. Xeriscape, Water Conservation Through Creative Landscaping.

Edwards Underground Water District. Records of Ground Water Recharge, Discharge, Water Levels, and Chemical Quality of Water for Edwards Aquifer in the San Antonio Area, Texas, 1934-1982.  Bulletin 42, March 1985.

Edwards Underground Water District. The Water Source, a Quarterly Publication of Edwards Underground Water District. March 1990. 

Edwards Underground Water District. Pamphlet, Edwards Underground Water District, 1992.

Edwards Underground Water District. Urban Development on Edwards Aquifer Recharge Zone. Prepared by Planning and Environmental Management Division. August 1993.

Edwards Underground Water District. Annual Report, 1993-1994.

Fambrough, J.  Who Owns Groundwater?  Tierra Grande, April 2000.

HDR Engineering, Inc. Recharge Enhancement Study Guadalupe-San Antonio River Basin.  Volume II Technical Report. EUWD, 1993.

HDR Engineering, Inc. Edwards Aquifer recharge enhancement project phase IVA.  Nueces River Basin. EUWD, June 1994.


Illgner, Rick. Comprehensive Water Management Plan General Managers Report.  EAA 2000.

McKinney, Daene C., and Sharp, John M. Springflow Augmentation of Comal springs and San Marcos Springs, Texas: Phase I. Center for Research in water Resources, Technical Report CRWR 247. Austin, 1995.

Meffe, G.K, and Carrol, C.R., eds.  1997.  Principles of Conservation Biology.  Sunderland, Massachusetts: Sinauer Associates.

Needham, J.  “Water-use restrictions looming.”  San Antonio Express New.  4/27/00.

Poteet, Collier, and Maclay. Investigation of the Fresh/Saline-Water Interface in the Edwards Aquifer In New Braunfels and San Marcos, Texas.  EUWD Report, 1992.

San Antonio Express-News, SAWS Mulling its Options, Saturday March 18, 2000.

San Antonio Express-News.  Subdivision OK’d for Comal Springs Ranch.  March 25-2000.

San Antonio Water System.  Watersaver Landscape Rebate Planning Guide. 1998.

Texas Administrative Code. Title 31, chapter 711 on groundwater withdrawal.

Texas Senate Bill 1477, bill number TX73RSB 1477. (5/31/1993)

Thomas, Sabine F.  Division of Earth and Physical Sciences.  The University of Texas San Antonio. Texas 78249-00663.

United States Fish and Wildlife Service.  1995.  San Marcos/Comal (Revised) Recovery Plan.  Albuquerque, New Mexico.

Votteler, T.  1998.  The little fish that roared: the Endangered Species Act, state groundwater law, and private property rights collide over the Texas Edwards Aquifer.  Environmental Law.

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