United States Department of the Inteiior
U.s. Geological Survey
Austin. Texas 78754-3898
October 16, 1996
Mr. Stephen Helfert, Field Supervisor
U.S. Fish and Wildlife Service
10711 Burnet Road, Suite 200
Austin, TX 78758
Dear Mr. Helfert:
Your agency requested that I provide a written evaluation of the effectiveness of current and proposed State rules in maintaining the current water-quality conditions for Barton Springs and associated Edwards aquifer. The purpose of this letter is to provide a response to that request.
My evaluation is based on four documents provided to me during a June 20, 1996 meeting between members of the Governors office. Texas Natural Resource Conservation Commission (TNRCC), Texas Department of Transportation (TXDOT), Texas Parks and Wildlife Department (TPWD), U.S. Fish and Wildlife Service (USFWS), U.S. Geological Survey (USGS), and Department of Interior. The purpose of the meeting was to discuss proposed State rules and procedures in protecting the water quality of Barton Springs and associated Edwards aquifer.
The four documents represent:
- Texas Water Commission, Chapter 313, Edwards Aquifer
- Interoffice Memorandum dated May 10, 1996 from Mark Jordan of the
TNRCC to Andy Barrett of the Governor's Policy Office, subject:
Edwards Aquifer Water Quality Protection Measures.
- Letter dated July 9, 1996 from Barry McBee of the TNRCC to Steve
Helfert of the USFWS, subject: Proposed Listing of the Barton Springs
- A document entitled "Highway Construction", prepared by the TXDOT, which presents "... selected literature references and other information related to highway consuuction, water quality and the Edwards Aquifer"
My assessment also is based on professional familiarity with the hydrology and water quality of Barton Springs and associated Edwards aquifer, and some familiarity with other related aspects such as City of Austin envirommental ordinances. I did not have the time to thoroughly research each topic presented below, thus some of my evaluations might not be fully relevant or complete.
My evaluations am as follows:
Point 1: Many of the Edwards rules do not apply to the contributing area -- for example non-point source pollution is not addressed in the contributing area.
Evaluation 1: The water in the aquifer and discharge from Barton Springs originate from 354 square miles: 90 square miles over the recharge area (25 percent of the total area) and 264 square miles of contributing area upstream from the recharge area (75 percent of the total area). Therefore, 75 percent of the area contributing flow to Barton Springs and associated aquifer is not protected from non-point source pollution.
Point 2: The current Rules implicitly discourage underground and above ground storage tanks and lift stations. The proposed rules explicitly allow such such structures if they are at least 150 feet from identified critical environmental features.
Evaluation 2: Critical environmental features are identified only if they have surface expressions that are discovered - many caves and pore spaces, which could readily transmit tank leakage to the aquifer, are not visible at the surface. Also. leakage from storage tanks could infiltrate to the water table of the Edwards aquifer anywhere in the recharge area, not just proximate to identified critical environmental features. Leakage in the contributing area could move in the subsurface to the Edwards aquifer, or move as overland flow or subsurface movement to discharge to the creek, where it could flow to the recharge area and enter the aquifer.
Point 3: The Edwards Rules regarding non-point source pollution apparently do not require special protection for specific environmentally sensitive areas with the recharge area--rules are applied uniformly over the recharge area.
Evaluation 3: The relation of the water quality of Barton Creek and Barton Springs, for example, is identified in a USGS report published in 1986. Recharge waters from the Barton Creek watershed discharge to Barton Springs much more rapidly than does recharge from other basins. The recharge water from Barton Creek thus receives much less filtering in the aquifer than do other waters, thus it has a greater impact on the water quality of Barton Springs than does water from other basins. Also, water from the Barton Creek watershed originates as runoff from its recharge area and its contributing area -- the contributing area is much larger than the recharge area, thus most of the recharge water from Barton Creek originates from its contributing area. As identified above, the contributing area is not protected from non-point source pollution.
Point 4: The new Rules remove the Section 313 language stating that more stringent local rules must be followed.
Evaluation 4: This allows conflict with local jurisdiction and permits lower water-quality standards than might be desired by local jurisdiction.
Point 5a: There are no limits on impervious cover. Dependence is made on Best Management Practices (BMPs) to maintain current water-quality conditions.
Point 5b: The TNRCC is funded for plan review of Water Pollution Abatement Plans (WPAP) only--they will not conduct field inspections of the sites.
Point 5c: Apparently no money is appropriated for monitoring water quality at BMPs or overview of maintenance to determine if they meet performance standards.
Point 5d: The TNRCC apparently has no money or power to enforce maintenance of BMPs.
Evaluation 5: National studies of BMPs indicate that they are effective in removing some suspended solids but ineffective in attenuating dissolved water-quality constituents, thus BMPs alone are not effective in preventing water-quality degradation due to urbanization.
Also, water-quality studies of rural and urban basins in Austin (such as a 1990 USGS report entitled "Relation between urbanization and water quality of streams in the, Austin area, Texas) document that urbanized basins experience increases ranging from many hundred to several thousand percent in concentrations for most water-quality constituents, while local studies on the effectiveness of BMPs indicate that they remove only 30 to 70 percent of the concentrations of most water-quality constituents. For example, a 1987 USGS study of the "Effects of runoff controls on the quantity and quality of urban runoff at two locations in Austin, Texas" document no removal of dissolved solids; 27-percent removal of total nitrogen; and 60 percent removal of total organic carbon. These studies also indicate that BMPs alone will not prevent water-quality degradation due to urbanization.
Other particular rules, identified below, also have consequences that could contribute to degradation of the current water-quality conditions in the Edwards aquifer:
Point: Apparently the Executive Director of the TNRCC now can waive rules.
Point: Water-quality protection plans for special zones (greater than 500 acres) are not subject to public hearings or public input.
Point: The proposed changes to the Rules apparently eliminate the Technical Manual--that guidance would not longer be available to developers who want to use it.
Point: No money is provided for retrofit of BMPs. Apparently local governments would have to fund those endeavors.
Your agency might want to solicit comments on the Edwards Rules from the San Antonio Water System, City of San Marcos, Edwards Aquifer Research and Data Center, Edwards Underground Conservation District, Barton Springs-Edwards Aquifer Conservation District, and City of Austin. If you have any questions regarding my evaluations, please contact me at the address on this letter or at telephone number 873-3060.
Raymond Slade, Jr.
copy:Susan Rieff, Department of the Interior