This 2002 summary of findings highlights the most common water quality impairments found in Waller Creek.The Texas Commission on Environmental Quality is responsible for determining the status of water resources statewide including those in Austin Area. Its methodology for ranking these water bodies is reviewed and approved by the U.S. Environmental Protection Agency. From the most recent assessment, the condition of water bodies in the Austin area are summarized. The current status of nineteen water bodies is listed as impaired or of concern due to benthic macroinvertebrate community degradation, elevated bacteria levels, elevated toxins in sediments, or depressed dissolved oxygen concentrations. This information provides a standard of comparison for Austin water bodies state-wide and a source of information to target watersheds for special attention in protection and remediation efforts.Waller Creek Working Grou

Gosselink, Leila

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  FINDINGS OF THE DRAFT 2002 TEXAS WATER QUALITY INVENTORY AND 303(D) LIST FOR THE AUSTIN AREA   By Leila Gosselink, P.E. Watershed Protection and Development Review Department Environmental Resource Management Division  ABSTRACT  INTRODUCTION  The Texas Water Quality Inventory [305(b) report] is prepared by the Texas Commission on Environmental Quality (TCEQ) and submitted to the USEPA biennially in accordance with Section 305(b) of the Clean Water Act (CWA).  Recent guidance from the Environmental Protection Agency (EPA) directed the state to integrate the 305(b) Water Quality Inventory and 303(d) List for all waters of the state. Section 305(b) of the act requires states to report the extent to which water bodies attain designated water quality standards. The table below summarizes Austin area impairments and concerns identified in the statewide assessment.  Table 1 Summary of COA Water Bodies 2002 Status  Problem identified Number of water bodies affected Concern or Impairment Status 3 Impairment Impaired macrobenthic invertebrate community 4 Concern 4 Impairment Frequently elevated bacteria levels 5 Concern The Texas Commission on Environmental Quality is responsible for determining the status of water resources statewide including those in Austin Area.  Its methodology for ranking these water bodies is reviewed and approved by the U.S. Environmental Protection Agency.  From the most recent assessment, the condition of water bodies in the Austin area are summarized.  The current status of nineteen water bodies is listed as impaired or of concern  due to benthic macroinvertebrate community degradation, elevated bacteria levels, elevated toxins in sediments,  or depressed dissolved oxygen concentrations.  This information provides a standard of comparison for Austin water bodies state-wide and a source of information to target watersheds for special attention in protection and remediation efforts. SR-03-04-2002 TWQA Page 1 of 5 September 2003 Problem identified Number of water bodies affected Concern or Impairment Status 1 Impairment Depressed dissolved oxygen  2 Concern Elevated nutrients 8 Concern Elevated toxins in sediments 4 Concern   Water bodies that do not support their water quality standards, and for which existing controls are not adequate are placed on the 303(d) list of impaired water bodies. Concerns are also identified where the use assessment is met but elevated pollutants with indirect impacts are seen or a paucity of data limits the assessment. Assessments are based on five years of water quality data collected by the TNRCC and cooperating agencies under approved quality assurance guidelines. Watershed Protection and Development Review Department (WPDRD) staff has been working for many years to have City data incorporated into the TCEQ database through the Clean Rivers Program.   The 2002 assessment included many more area creeks as a result of the inclusion of City data. Both impairments and concerns were identified in the Austin area as described below, but none of them will currently require the development of a TMDL.  Development of a TMDL (Total Maximum Daily Load), a model to determine the capacity of the water body for the pollutant of concern and allocate this amount among the sources in the watershed, is required to identify actions to take to restore and maintain human uses or aquatic life.  The primary focus at this time for Austin area water bodies is continued monitoring.  Toxins in sediments and nutrients in water, of greatest concern to City staff, are addressed only as “secondary concerns” by the state as only screening levels rather than regulatory criteria have been adopted by the state.    IMPAIRED WATER BODIES  Many Austin water bodies were listed as not supporting their designated uses, many of these for elevated bacteria. The recreational uses are impaired when bacteria are elevated, while depressed dissolved oxygen or impaired macrobenthic communities indicate that the aquatic life support use may not be met. Many creeks were removed since the previous listing when USGS data for bacteria were removed from the TCEQ database.  Onion Creek impairments for elevated Total Dissolved Solids (TDS) and sulfate were also delisted when standards were revised to allow higher levels of these constituents; currently the TMDL for dissolved oxygen, which was initiated, has been downgraded as shown below to a data collection effort.  The table below lists water bodies in the Austin area designated as impaired, but none are categorized for TMDL development, but rather scheduled to obtain additional data.  Table 2 Individual Impairments of COA Water Bodies 2002 From:  “DRAFT 2002 Texas 303(d) List (October 1, 2002) Segment Water body Impairment area Impairment  Category* 1403A Bull Creek Lake Austin to upstream perennial portion  From most downstream xing to most upstream xing of Spicewood Springs Rd Impaired macrobenthos community 5c [rank D] 1403J Spicewood Tributary to Shoal Creek From MoPac to a point west of Hart Lane Entire water body Bacteria  5c [rank D] SR-03-04-2002 TWQA Page 2 of 5 September 2003 Segment Water body Impairment area Impairment  Category* 1403K Taylor Slough South From Lake Austin to west of Pecos Street Entire water body Bacteria  5c [rank D] 1427 Onion Creek From Colorado River to most upstream xing of FM165 From end of segment upstream to US183 Depressed dissolved oxygen  5c [rank D] 1427A Slaughter Creek Intermittent stream with perennial pools from Onion to above US290 Entire water body Impaired macrobenthos community  5c [rank D] 1428C Gilleland Creek Perennial stream and intermittent stream w/perennial pools from Colorado River to spring source From Taylor Lane upstream to Old Highway 20 Bacteria  5c [rank D] 1429B Eanes Creek From Town Lake to upstream perennial portion  Entire water body Bacteria 5c [rank D] 1429C Waller Creek From Town Lake to upstream portion  From Town Lake to East MLK Blvd. Impaired macrobenthos community  5c [rank D] Category 5 The water body does not meet applicable water quality standards or is threatened for one or more designated uses by one or more pollutants.  Category 5a A TMDL is underway, scheduled, or will be scheduled.  Category 5b A review of the water quality standards for this water body will be conducted before a TMDL is scheduled.  Category 5c Additional data and information will be collected before a TMDL is scheduled.  WATER BODIES WITH CONCERNS FOR USE ATTAINMENT For the first time in 2002, concerns for designated uses were also identified (Primary Concerns) by TCEQ.   • Use Concerns-Limited Data (Tier 1 Primary Concerns) are identified for indications where less than 10 samples were available for assessment and some exceedances were identified.  • Use Concerns (Tier 2 Primary Concerns) are identified for indicators that support the designated use as determined by an adequate number of samples, but a few reported exceedances indicated a potential water quality problem. Water bodies with Tier 1 and Tier 2 concerns receive high priority for additional monitoring.  Table32 Individual COA Water Bodies with Water Quality Concerns 2002 From: “DRAFT 2002 Summary of Water Bodies with Concerns for Use Attainment” Segment Concern Location Use Level of Concern [Tier 1 or Tier 2] Parameter of Concern 1403 Lake Austin Quinlan Park to upper end of segment Aquatic Life Use Use Concern [T2] Depressed dissolved oxygen 1403E Stillhouse Hollow [Bull Creek unclassified water body] Entire water body Aquatic Life Use Use Concern-Limited Data [T1] Impaired macrobenthos community 1403G Tanglewood Tributary to Bull Creek Entire water body Contact Recreation  Use Concern [T2] Bacteria SR-03-04-2002 TWQA Page 3 of 5 September 2003 Segment Concern Location Use Level of Concern [Tier 1 or Tier 2] Parameter of Concern 1403R Unnamed tributary to Lake Austin Entire water body Contact Recreation  Use Concern [T2] Bacteria 1428B Walnut  From FM 969 upstream to Loyola Contact Recreation Use Concern-Limited Data [T1] Bacteria  1428B Walnut From Sprinkle Road upstream to IH35 Aquatic Life Use Concern- Limited Data [T1] Impaired macrobenthos community 1428C Gilleland Creek From Taylor Lane upstream to Old Highwa 20 Contact Recreation Use Concern [T2] Bacteria 1428D Little Walnut From Walnut Creek upstream to US183 Aquatic Life Use Concern-Limited Data [T1] Impaired macrobenthos community 1429C Waller Creek From Town Lake to East MLK Blvd  And upper portion of creek Contact Recreation Use Use Concern-Limited Data [T1] Bacteria 1430 Barton Creek From confluence with Town Lake to Barton Springs Pool most downstream dam Aquatic Life Use Use Concern-Limited Data [T1] Impaired macrobenthos community 1430A Barton Springs Barton Springs Pool Aquatic Life Use Use Concern [T2] Depressed dissolved oxygen   WATER QUALITY CONCERNS Finally, there is also a summary of water bodies with water quality concerns (Secondary Concerns).  These are designated by exceedances of screening levels for nutrients, chlorophyll a, toxic substances in sediment, and toxic substances in fish tissue that do not cause direct impairment of designated uses. In Austin, the majority of concerns were for the water bodies with elevated nutrients listed below.  Austin tributaries with nutrient enrichment include both creeks and portions of the Colorado River.    Barrow Preserve,   Stillhouse Hollow,   Spicewood Tributary,   Taylor Slough South,  Colorado River Below Town Lake,  Walnut Creek,  Gilleland Creek), and the  Lower half of Town Lake.  Additional secondary concerns listed below include impaired biological communities in the Colorado River below Town Lake.  This reach of the river was designated for exceptional aquatic life use in the mid-1990s.  Other concerns are related to toxins in sediment. The sediment sampling conducted by WPDRD has focused on problem areas such urban creeks or below localized inputs.  The levels of toxins in sediments are screened by TCEQ against both a level indicating possible biological impacts and the 85th percentile of measurements in the state.  Initial ambient toxicity testing by the City, which is required by the state for designating an impairment did not identify toxicity except at two dry tributary sites with photo exposure.  Phototoxicity is SR-03-04-2002 TWQA Page 4 of 5 September 2003 not, however, a method approved by the state. Continued sampling being conducted by the state may indicate whether concerns are warranted and potential sources, however, phototoxicity is not being evaluated.  Colorado River Below Town Lake – impaired fish and macrobenthos community   Waller Creek – narrative concern for lead and organics in sediment [future monitoring by UT]  East Bouldin Creek – metals and organics in sediment  Barton Creek (Pool to 2 miles upstream of Loop 1) – PAHs, cadmium, lead, silver, and zinc in sediment  Barton Springs Pool – arsenic and copper in sediment   CONCLUSIONS  As shown above a significant number of water bodies did poorly in statewide ratings.  The City is continuing to participate in the statewide coordinated monitoring program and the Clean Rivers Program to provide data to the state.  Efforts to correct problems identified by the City in the Barton Creek system have initiated additional monitoring by the state of sediments and programs to correct the problems by the City.  Funds for corrective actions from TCEQ and the USEPA are limited due to the lack of sites identified for TMDL status.   SR-03-04-2002 TWQA Page 5 of 5 September 2003 

Findings of the DRAFT 2002 Texas Water Quality Inventory and 303(d) List for the Austin Area

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Findings of the DRAFT 2002 Texas Water Quality Inventory and 303(d) List for the Austin Area

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