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Texas Environmental Almanac, Chapter 2, Water Quality, Page 6
While Texas has no state-level stormwater permitting program, municipal and industrial wastewater permits may include requirements to regulate the discharge of stormwater runoff. In 1991, for example, 439 of 966 industrial permits regulated stormwater discharges from industry.(62)

Because the federal government has not delegated to Texas responsibility for the National Pollutant Discharge Elimination System (NPDES) program, federal stormwater permits are issued by the Environmental Protection Agency. The 1987 amendments to the Clean Water Act required that stormwater discharges be permitted in two phases. Phase 1, which has been completed across the nation, required all pre-1987 dischargers as well as industries, construction projects covering more than five acres, and cities of more than 100,000 population with a separate stormwater sewer system to obtain a National Pollutant Discharge Elimination System permit. Under Phase II, which began October 1, 1994, most other stormwater dischargers, including cities of less than 100,000 population and businesses such as commercial and retail outlets may be required to obtain an National Pollutant Discharge Elimination System permit.


The state has ranked its rivers, streams, reservoirs and bays in terms of severity of pollution. The ranking system was based in part on how well the water body met traditional water-quality parameters (bacteria, chlorides, dissolved oxygen content, temperature, etc.), and in part on such criteria as reported fish kills, known municipal and industrial wastewater discharges, extent of non-point-source pollution, known toxicity problems and other information.(64) The most polluted rivers are concentrated in southeast and central south Texas. The most polluted reservoirs and lakes are mainly in central and eastern Texas.



Lack of Monitoring23100%
High Fecal Coliform Levels2087%
Toxic Materials1878%
Depressed Dissolved Oxygen Levels1461%
Excess Chlorides1252%
Non-Point-Source Pollution626%
Excessive Vegetation626%
Shellfish Harvesting Closures/ Fishing Advisories417%
Septic Tanks417%
Oil and Gas Degradation417%
Loss or Degradation of Habitat313%
Salt Water Contamination313%
Excess Total Suspended Solids29%
Fish Kills29%

Source: Texas Water Commission, Summary Report: Regional Assessments of Water Quality Pursuant to the Texas Clean Rivers Act (Austin: TWC, December 1992), 12.


Under a 1991 state law, local river authorities and coastal basin authorities are required to assess their river basins every two years, identifying major water quality issues. In 1992, all river authorities identified the lack of monitoring, and the resulting limited water-quality data, as the major water quality issue.(65)

For a number of river authorities, a high level of fecal coliform bacteria was identified as a major water quality problem. Water quality standards for fecal coliform are designed to prevent human illness since they are an indicator of other pathogens that cause infectious diseases like hepatitis and cholera. High fecal coliform levels were found in 20 of the 23 coastal and river basins and 49 percent of all classified segments. The high levels in the coastal areas have led to the closing of oyster harvesting areas.

Other river authorities identified toxics as a major concern. Many toxic chemicals, including pesticides, solvents and other organics and inorganic chemicals and metals have been linked to birth defects, cancer and other diseases. Specific toxic materials identified by river authorities, based on limited monitoring data, include pesticides like Aldrin, and PCBs, banned for new uses. Most toxicity problems pinpointed by the river basin assessments relate to high levels of nickel, zinc, cadmium, lead, mercury and other heavy metals, which probably are from industrial sources. In about 23 percent of the reported cases of fish kills over the last four years, toxic pollutants were the cause.(66) In two water bodies, the Rio Grande downstream of Laredo/Nuevo Laredo, and the Alligator Bayou in the Neches-Trinity coastal river basin, unusually high numbers of fish abnormalities indicate problems with toxic pollutants.(67)

Fourteen of the river authorities identified low oxygen levels as a major water quality concern. This condition, also referred to as high biological oxygen demand (BOD), is considered one of the most obvious indicators of degraded water quality because it directly impacts aquatic life. It may result from high nutrient levels, urban runoff, or excessive organic loading from wastewater discharges.

Eight river authorities identified high levels of nutrients - usually phosphorus, nitrogen ammonia and nitrates - as a major water quality issue. Wastewater discharges, improperly functioning wastewater systems, septic tanks, agricultural run-off and other kinds of non-point-source pollution were identified as probable sources of these nutrient loadings. While excess plant nutrients pose no direct threat to human health, they do lead to excess vegetation which can choke off rivers and lakes and eventually reduce dissolved oxygen, affecting fish and other aquatic species.

Three coastal-area river authorities listed degradation of habitat as a major water quality concern. Development, erosion and the dredging and filling of coastal areas have destroyed some animal habitat in rivers and streams. The result has been a reduction in biodiversity in the area.

In addition to these water quality problems identified by river authorities, excessive levels of toxics such as metals and pesticides in edible fish tissue has led the Texas Department of Health to issue total bans on consumption of fish and shellfish in four river segments, one entire reservoir and two bay segments (see "Coastal Water" section for details). The Texas Department of Health has issued fish consumption advisories in 14 other water bodies.(72)

Fishing in areas that have been closed to fishing and keeping those fish is a violation of state law. Most recently, following the discovery of fish contaminated with high levels of PCBs, the Department of Health declared the Donna Reservoir and Irrigation Canal closed to fishing.

Restricted or No-Consumption Advisories
Welsh Reservoir19921365 acresSeleniumPower plant
Brandy Branch Reservoir" "1240 acres" "" "
Martin Creek Reservoir" "5020 acres" "" "
Neches River Tidal19907 milesDioxinPaper mill
Neches River" "24 miles" "" "
Houston Ship Channel/San Jacinto River199012 milesDioxinPaper mill
Houston Ship Channel" "6 miles" "" "
Houston Ship Channel/Buffalo Bayou" "14 miles" "" "
Upper Galveston Bay" "22 square miles" "" "
Clear Creek Tidal19938 milesVolatileHazardous waste site
Clear Creek above Tidal" "30 milesOrganic Compounds" "
Brazos River Tidal199023 milesDioxinChemical industry
Town Lake, Austin1990500 acresChlordaneUrban runoff
Arroyo Colorado above Tidal198063 milesChlordane, Toxaphene, DDTAgricultural and urban runoff
Aquatic Life Closures
Upper Trinity River199019 milesChlordaneUrban runoff
West Fork Trinity River" "22 miles" "" "
Clear Fork Trinity River" "1 mile" "" "
Lower West Fork Trinity River" "27 miles" "" "
Donna Reservoir1994333 acresPCBsUnknown
Lavaca Bay198854.8 sq milesMercurySpill
Cox Bay" "2.9 sq miles" "" "

Source: Texas Natural Resource Conservation Commission, State of Texas Water Quality Inventory, 12th Edition (Austin: TNRCC, 1995), 171 - 172.


Like most states, Texas has no comprehensive fish monitoring program. The state does test fish tissue for contaminants when a report of a chemical
spill or some other information leads state health officials to believe human health may be threatened. But no systematic monitoring is done in the absence of these reports. Testing fish is expensive; a detailed tissue sampling of one fish might cost $500 and a full scan, which examines the liver and reproductive organs to pinpoint sources of dangerous contaminants, might exceed $1,000 per sample.(68)

The Texas Department of Health's Shellfish Control Division is charged with surveillance of miles of oyster-harvesting areas along the Gulf Coast and has the authority to close bays and estuaries. This program is funded in part by a $1-per-sack fee paid by oyster fishermen. But no comparable revenue source is available for testing inland fish.

Yet there is evidence that such monitoring is warranted. In 1993, the Environmental Protection Agency conducted a study on the types of environmental problems to which Texas families living along the border are exposed. As part of the study, EPA tested a carp caught by a Brownsville family from the Donna Reservoir. The tests of the fish's tissue revealed PCB levels of 400 parts per million, or 200 times the recommended limit for human consumption.(69) When further tests of Donna Reservoir fish identified eight more fish contaminated by PCB, the Texas Department of Health issued a fish consumption advisory for the reservoir and its connecting canals. Ten more PCB-contaminated fish caught from an irrigation canal between the reservoir and the Rio Grande River were found in January 1994. Following this study, Texas Department of Health banned any taking or consumption of fish in the area.(70)

PCBs have been banned in the U.S. since the late 1970s because they cause liver disorders and developmental delays in infants. (The only exception is for use in electrical transformers.) To date, officials have been unable to identify the source of the PCBs found in the Donna area.

While startling, the problems at Donna with PCBs are not unique. Over the last ten years, Texas Natural Resource Conservation Commission officials have also identified nine segments around the state where concentrations of PCBs in whole fish tissue has been above concern levels.(71)

Texas Environmental Almanac, Chapter 2, Water Quality, Page 6

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