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
Salamander. - 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.
Sincerely
Raymond Slade, Jr.
Hydrologist
copy:Susan Rieff, Department of the Interior
This article appears in December 13 • 1996 and December 13 • 1996 (Cover).