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Research about Trinity River Basin

Source-linked reports with geographic coverage including Trinity River Basin.

11 recordsLinked to original sources
USGS2023

The use of historical data and global climate models to assess historical and future surface water and groundwater availability in the Trinity River Basin in Texas

This paper describes the results of a study that was done by the USGS to assess recent (2017) water availability, forecast long-term trends in water availability, assess changes in water availability, and forecast future water availability in the Trinity River Basin in Texas. The Trinity River Basin surface water model and Trinity River alluvium aquifer (TRAA) groundwater model were created to evaluate future conditions under different global climate models (GCM). The results of this study show minimal overall changes in water availability for both surface water and groundwater. Trend analyses using historical data (1900–2017) indicated an increase of annual precipitation on the watersheds that drain into the reservoirs in Regional Water Planning Group C. However, the Trinity River Basin surface water model GCM ensemble mean annual precipitation indicates a downward trend, resulting in a downward trend in surface runoff. Additionally, the GCM ensemble mean for the Trinity River Basin surface water model and the TRAA groundwater model both indicate a downward trend in recharge while the TRAA model GCM ensemble mean indicates an upward trend in the amount of groundwater leaving the aquifer to rivers and streams resulting in an upward trend of cumulative storage change.

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USGS2007

Trinity River Basin, Texas

In 1991 the Trinity River Basin National Water-Quality Assessment (NAWQA) will include assessments of surface-water and ground-water quality. Initial efforts have focused on identifying water-quality issues in the basin and on the environmental factors underlying those issues. Physical characteristics described include climate, geology, soils, vegetation, physiography, and hydrology. Cultural characteristics discussed include population distribution, land use and land cover, agricultural practices, water use, an reservoir operations. Major water-quality categories are identified and some of the implications of the environmental factors for water quality are presented.

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USGS1997

Water-quality assessment of the Trinity River Basin, Texas — Nutrients and pesticides in the watersheds of Richland and Chambers Creeks, 1993-95

A study of nutrients and pesticides was conducted during February-August 1995 in the west-central part of the Trinity River Basin, where land commonly is used for growing crops. Water and bed-sediment samples were collected at 8 small reservoir sites in the headwaters (known as Natural Resources Conservation Service reservoirs), at 5 stream sites, and at 3 Richland-Chambers Reservoir sites. The analysis included data from the Chambers Creek near Rice site (08064100), which was sampled repeatedly during March 1993-September 1995. Total nitrogen concentrations in the Natural Resources Conservation Service reservoirs were less than 1.0 milligram per liter, as nitrogen, except in 2 of the 8 reservoirs. For the five stream sites, total nitrogen concentrations at the beginning of the study ranged from 0.5 to 1.8 milligrams per liter. Peaks were noted in all stream sites during either March or April; the greatest peak concentration was 4.8 milligrams per liter, as nitrogen. By the end of the study, concentrations decreased to less than 1.2 milligrams per liter, as nitrogen. In the Richland-Chambers Reservoir, the February-March and June sampling showed total nitrogen concentrations of about 0.6 milligram per liter, as nitrogen. At the beginning of the study, all five of the stream sites had total phosphorus concentrations less than 0.04 milligram per liter, as phosphorus. Peak concentrations in the streams occurred in the May sampling except at one site. Two sites had concentrations greater than 0.2 milligram per liter, as phosphorus. By the end of the study, concentrations decreased to less than 0.04 milligram per liter, as phosphorus, except at one site where the concentrations were about 0.08 milligram per liter. Concentrations in the Richland-Chambers Reservoir were less than 0.04 milligram per liter, as phosphorus. Total nitrogen and total phosphorus concentrations generally increased with streamflow and with the percentage of cropland in the drainage area upstream from the sampling site. Herbicides were detected in the streams much more often than insecticides were. Nineteen herbicides and 9 insecticides were detected at the 08064100 Chambers Creek near Rice site. Atrazine and metolachlor, the most commonly detected herbicides, occurred in all samples at this site. Other herbicides detected in 25 percent or more of the samples were alachlor, fluometuron, prometon, simazine, trifluralin, and 2,4-D. At the beginning of the study, the number of herbicides detected in the five stream sites was 4 or 5. The greatest number of herbicides detected in the streams occurred in May samples, ranging from 7 to 10. The number of herbicides detected in the Richland-Chambers Reservoir ranged from 6 to 8. Generally, more herbicides were detected in high-streamflow samples than in low-streamflow samples. However, a consistent relation between the number of herbicides in samples and the percentage of cropland in a drainage area was not evident. At the beginning of the study, atrazine concentrations at the stream sites were less than 0.4 microgram per liter, except at one site. In the streams, concentrations peaked in March and April; the greatest peak concentration was 20 micrograms per liter. By the end of the study, atrazine concentrations decreased to less than 0.4 microgram per liter at all the stream sites. In the Richland-Chambers Reservoir, the concentrations were about 1 microgram per liter during February-March and about 3 micrograms per liter in June. Atrazine concentrations tended to increase with increasing streamflow. A consistent relation between atrazine concentrations and the percentage of cropland in a drainage area was not evident. The greatest number of insecticides detected in water samples was two. Diazinon, the most frequently detected insecticide, had slightly greater concentrations in May and June - between 0.01 and 0.02 microgram per liter. The only organochlorine insecticides detected in bed-sedime

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USGS1996

Water-quality assessment of the Trinity River Basin, Texas — Pesticides in streams draining an urban and an agricultural area, 1993-95

Water and bed-sediment samples from streams draining an urban and an agricultural area in the Trinity River Basin, Texas, were analyzed. The samples were collected during March 1993?September 1995 by the Trinity River Basin study-unit team of the National Water-Quality Assessment Program. A comparison of pesticide data for water samples from seven streams in the Dallas-Fort Worth urban area with five streams in an agricultural area in the west-central part of the Trinity River Basin showed detections of 24 herbicides in urban-area streams and 19 herbicides in agricultural-area streams and 10 insecticides in each area. Atrazine, a herbicide, was detected in all samples from both areas. Diazinon, an insecticide, was detected in all samples collected in urban-area streams and in about 60 percent of the samples collected in agricultural-area streams. Concentrations of alachlor, atrazine, fluometuron, metolachlor, and pendimethalin (herbicides) were always greater in agricultural-area streams, and prometon and simazine concentrations were always greater in urban-area streams. Atrazine was the only herbicide with concentrations greater than a health advisory limit of 3 micrograms per liter. Concentrations were greater in about 20 percent of the samples; all were in the agricultural area and occurred during spring and during higher streamflow. Diazinon was the only insecticide with concentrations greater than the health advisory of 0.6 microgram per liter. Concentrations were greater in about 15 percent of the samples from the urban area. All exceedances were during spring through early fall and during all ranges of streamflow. In the agricultural area, atrazine and metolachlor concentrations peaked during spring and early summer and increased with increasing streamflow; in the urban area, carbaryl, chlorpyrifos, and diazinon peaked in April and remained relatively high during the summer and increased with increasing streamflow. A comparison of pesticide data for bed-sediment samples from five urban streams and five agricultural streams showed detections of 11 organochlorine insecticides in the urban area and 1 in the agricultural area. All compounds were either DDT-related or one of the components of chlordane except for mirex and dieldrin.

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USGS1995

National Water-Quality Assessment Program— Pesticides in the Trinity River Basin study unit, Texas, 1968-91

The Trinity River Basin National Water Quality Assessment (NAWQA) study-unit staff began assessment activities in 1991, and in 1992, undertook a retrospective review of existing data on pesticides. The main purpose of this review was to aid in the design of a pesticide-sampling network for the study unit. The review consisted of the compilation, screening, and analysis of available pesticide-sample information. In addition, important environmental factors, which influence the occurrence and distribution of pesticides in the study unit, were identified and compiled. A report of this review and analysis will be released in 1995 (Ulery and Brown, in press). This fact sheet provides a brief overview of significant findings.

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USGS1995

Water-quality assessment of the Trinity River Basin, Texas—Data collection, 1992–95

Assessment activities in the Trinity River Basin study unit of the National Water-Quality Assessment (NAWQA) Program began in October 1991 with 2 years dedicated to planning, analyzing existing information, and designing data-collection networks. In October 1993, a 3-year intensive data-collection program was initiated. Guidelines were provided by the NAWQA Program National Synthesis team, and suggestions for networks and surveys were made by the study unit’s liaison committee. This fact sheet describes the data-collection activities.

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USGS1995

Water-quality assessment in the Trinity River Basin, Texas; pesticide occurrence in streams, winter and spring 1994

A consistent, basin-wide set of data for streams in the Trinity River Basin is necessary to provide a baseline for current conditions, to compare with historical data, and to provide a reference for future studies by the National Water-Quality Assessment (NAWQA) Program. In addition, the basin-wide surveys begin the process of addressing the cause-effect relation for water quality in the basin. Effects of land use, geology, vegetation, soils, and reservoirs on water quality were considered by site selection. Seasonal differences were addressed by conducting two surveys, the first during the winter low-flow period and the second during the late spring high-flow period.

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USGS1995

Water-quality assessment in the Trinity River Basin, Texas: Nutrient concentrations in streams winter and spring 1994

A consistent, basin-wide set of data for streams in the Trinity River Basin is a necessary baseline to compare current conditions with historical data and to provide a reference for future studies. In addition, the basin-wide surveys begin the process of addressing the cause-effect relations for water quality in the basin. Effects of land use, geology, vegetation, soils, and reservoirs on water quality were considered in selection of sites. Seasonal differences were addressed by conducting two surveys, the first during the winter low-flow period and the second during the late spring high-flow period.

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USGS1995

Water-quality assessment of the Trinity River Basin, Texas— Analysis of available information on nutrients and suspended sediment, 1974-91

The U.S. Geological Survey is conducting an assessment of water quality in the Trinity River Basin as part of the National Water-Quality Assessment Program. During the planning phase of this study, existing information on nutrients and suspended sediment was compiled and analyzed. A total of about 5,700 water-quality samples were analyzed from local, State, and Federal agencies. Of these, about 4,200 were from streams and about 1,500 were from wells. Additionally, atmospheric deposition data for two locations were obtained and analyzed. Spatial variations in nutrient concentrations in streams are related primarily to point sources and reservoirs. Median total nitrogen concentrations downstream from major point sources, downstream from reservoirs, and on tributaries were 6.0, 1.3, and 2.4 milligrams per liter, respectively. Median total phosphorus concentrations for the same three settings were 1.6, O. 1, and 0.2 milligrams per liter, respectively. The largest concentrations occurred at low flow downstream from Dallas, Texas, when streamflow dominated by treated wastewater from point sources. The smallest concentrations occurred immediately downstream from reservoirs, which act as sinks for nutrients. Nutrient concentrations in agricultural areas were positively correlated to percent of drainage in agricultural land use and to discharge, indicating washoff of nutrients from nonpoint sources during storms. As with concentrations, nutrient loads were related to the presence of point sources and reservoirs. Loads increased substantially in the Dallas-Fort Worth area with the addition of nutrients from point sources; loads decreased substantially as flow passed through Livingston Reservoir. Concentrations of total nitrogen and total phosphorus did not change significantly, at the 95 percent confidence level, from 1974 to 1991 at most sites. The exception was a decrease in phosphorus concentrations at two sites downstream from major wastewater-treatment plants in the Dallas area. Concentrations of organic nitrogen and ammonia declined and concentrations of nitrite plus nitrate increased at sites below major wastewater-treatment plants. These changes are indicative of improvements in wastewater treatment that converts organic nitrogen and ammonia to nitrite and finally nitrate. Because nitrogen conversion reactions consume oxygen, the occurrence of these reactions at the treatment plants instead of in the streams resulted in reduced loading of biochemical oxygen demand to the streams. The only nutrient measured in ground water was nitrate. Nitrate concentrations varied by aquifer with the largest median concentrations in the Queen City and Nacatoch aquifers. There was a significant rank correlation between nitrate concentrations and depth of well for all seven aquifer groups sampled, with largest concentrations present in shallow wells. The large concentrations could result from nonpoint sources of nitrate associated with agricultural and urban land use; however, attempts to correlate nitrogen fertilizer application rates and agricultural land use to concentrations of nitrate in ground water were inconclusive. Only limited suspended-sediment data were available. Four sites had daily sediment-discharge records for three or more water years (October 1 to September 30) between 1974 and 1985. An additional three sites had periodic measurements of suspended-sediment concentrations. There are differences in concentrations and yields among sites; however, the limited amount of data precludes developing statistical or cause-and-effect relations with environmental factors such as land use, soil, and geology. Data are sufficient, and the relation is pronounced enough, to indicate trapping of suspended sediment by Livingston Reservoir.

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USGS1995

Water-quality assessment of the Trinity River Basin, Texas - Review and analysis of available pesticide information, 1968-91

In 1991 the Trinity River Basin study unit was among the first 20 study units in which work began under full-scale program implementation of the National Water-Quality Assessment Program. A retrospective assessment was undertaken to review and analyze existing pesticide data and related environmental factors. Population and land-use data indicate human modifications to the landscape and hydrologic system of the study area during the period 1968–91. A variety of crops treated with pesticides were identified, with wheat and cotton accounting for the largest number of acres treated annually (541,250 and 519,870 acres, respectively). Agricultural-use estimates for the later period covered by this report (1988–90) indicate that 105 different pesticides were used and that 24 pesticides accounted for 75 percent of average agricultural use in the study area. Sorghum was treated by the largest number of the 24 mostused pesticides, and cotton was treated by the second largest number of those pesticides. Dimethoate and methyl parathion were the most heavily used of the organophosphate class pesticides. The herbicide 2,4–D was the most heavily used chlorophenoxy pesticide. Carbamate pesticides are used extensively in the study area, with carbaryl, carbofuran, methomyl, and thiodicarb accounting for the majority of the use of this class of pesticide. Miscellaneous pesticides included alachlor, arsenic acid, picloram, and glyphosate, among others. The data indicate that herbicide use generally is proportionally higher in the study area than in the Nation, and that insecticide use in the study area generally is proportionally lower than in the Nation. Eight different agencies collected the waterquality data used in this report. Samples were collected by all agencies at a combined total of 155 surface-water sites and 121 ground-water sites. The sampled media included water, bed sediment, and tissues of fish and other aquatic wildlife. Some 273 samples for analysis of the herbicide 2,4–D were collected as part of the city of Arlington’s data-collection program. The herbicide was detected in 74 percent of the samples, but none exceeded the Maximum Contamination Level for drinking water. Dallas Water Utilities collected pesticide samples during a storm in February 1977. Samples were collected at 17 sites with detections of some pesticides in over 50 percent of the samples. Diazinon was detected in 56 percent of samples and 2,4–D was found in 56 percent of samples. Texas Parks and Wildlife Department collected samples from fish tissue for analyses of organochlorine pesticides from 15 sites in the Dallas-Fort Worth area. Chlordane concentrations in some of the samples exceeded the Food and Drug Administration’s action level of 300 micrograms per kilogram. The Texas Water Commission collected ground-water samples in the study area during 1990 for the major types of pesticides and none were detected. No arsenic was detected in samples from 121 wells in or near the study area. Organochlorine and organophosphate samples were collected beginning in 1974 and ending in 1991. Concentrations of organochlorine pesticides in bed sediment decrease with increasing distance downstream from the Dallas-Fort Worth urban area. Pesticide samples collected by the U.S. Geological Survey indicated significant rank correlation between number of detects of chlordane and the percent of the contributing watershed classified as urban land use. Dieldrin in bed sediment samples, and lindane, diazinon, and malathion, in water samples, also were significantly correlated with urban land use. Chlordane and dieldrin were significantly correlated with distance downstream from the Dallas-Fort Worth urban area. Review of all available data showed that pesticides were detected to a substantial degree in various sample media over the time period covered by this report. The authors were able to locate little pesticide-sample data for ground water or for tributary streams because sampling efforts historically have been concentrated on the mainstem Trinity River.

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