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Research about Red River alluvial aquifer

Source-linked reports with geographic coverage including Red River alluvial aquifer.

3 recordsLinked to original sources
USGS2025

Hydrogeologic framework and conceptual model of the Red River alluvial aquifer east of Lake Texoma, southeastern Oklahoma, 1980–2022

The 1973 Oklahoma Groundwater Law (Oklahoma Statutes §82-1020.5) requires that the Oklahoma Water Resources Board conduct hydrologic investigations of the State’s groundwater basins to support a determination of the maximum annual yield for each groundwater basin. At present (2025), the Oklahoma Water Resources Board has not established a maximum annual yield for the Red River alluvial aquifer east of Lake Texoma. To support the evaluation and determination of a maximum annual yield, a hydrogeologic framework and conceptual groundwater-flow model were developed to assess groundwater availability in the Red River alluvial aquifer east of Lake Texoma. The scope of this hydrologic investigation is the alluvium and terrace containing the Red River alluvial aquifer in Oklahoma between Lake Texoma, the Texas State line, and the Arkansas State line, an extent referred to in this report as “the eastern part of the Red River alluvial aquifer.” Parts of the alluvium and terrace extent in Arkansas and Texas are included in some analyses to address hydrologic influences from outside the aquifer’s boundaries in Oklahoma. The eastern part of the Red River alluvial aquifer in southeastern Oklahoma consists of approximately 401,280 acres of Quaternary alluvium and terrace deposits associated with the Red River and its major tributaries. Mean annual recharge to the aquifer for the 1980–2022 study period was estimated to be 8.62 inches per year, or 17.98 percent of the mean annual precipitation over the same period (47.94 inches). This mean annual recharge rate is equivalent to an inflow of approximately 288,250 acre-feet per year for the eastern part of the Red River alluvial aquifer. Recharge estimated using the Soil-Water-Balance code accounts for 98.7 percent of the conceptual-model inflows to the eastern part of the Red River alluvial aquifer. Saturated-zone evapotranspiration accounts for 11.9 percent and net streambed seepage accounts for 87.4 percent of the outflows in the conceptual model.

Arkansas, Oklahoma, Texas↗
USGS1980

Chemical character of water in the Red River alluvial aquifer, Louisiana

The Red River alluvial aquifer of Louisiana underlies approximately 2,000 square miles in the Red River Valley of Louisiana. The aquifer is Pleistocene in age and consists of clay, silt, sand, and gravel deposited by the Red River. Sand and gravel constitute the lower two-thirds of the deposit, the most productive part of the aquifer. The aquifer ranges from 40 to 150 feet in thickness and reaches its maximum thickness in Avoyelles and Catahoula Parishes. Fine sand, silt, and clay of Holocene age overlie and generally confine the aquifer. These fine-grained deposits generally do not exceed 50 feet in thickness. The aquifer is recharged by downward seepage of rainfall in the valley, by lateral movement of water from adjacent Pleistocene and Tertiary formations, and by upward movement of water from underlying formations of Tertiary age. When large quantities of seepage occur locally within short periods of time, a temporary reduction in mineralization takes place in the upper part of the aquifer. Lateral recharge from Pleistocene and Tertiary formations generally upgrades water in the alluvial aquifer near the edge of the valley. Recharge from underlying aquifers may upgrade or downgrade the quality of water in the lower part of the alluvial aquifer. The Red River and its major tributaries recharge the Red River alluvial aquifer in local zones near the river during high stream stages, but noticeable water-quality changes occur only following periods of prolonged high stages. Ground water in the alluvium generally moves toward the streams and down the valley. Water levels fluctuate seasonally and are generally less than 30 feet below land surface. Annual water-level fluctuations have a maximum range of about 30 feet near the Red River, and a minimum range of only a few feet in some interstream areas. The Red River alluvial aquifer can yield 2,000 gallons per minute or more of water to individual wells where thick beds of coarse sand and gravel occur in the southern part of the study area. Aquifer tests indicate that the transmissivity ranges from 2,000 to 27,000 feet squared per day. The hydraulic conductivity ranges from 100 to 300 feet per day. Storage coefficients range from 6.0x10 -4 to 1.0x10 -3 . Water in the aquifer typically is of the calcium magnesium bicarbonate type. The water is hard to very hard, ranging in hardness from about 100 to 2,300 mg/L (milligrams per liter). However, hardness generally is in the 200- to 600-mg/L range. The ions that appear to be most variable in occurrence and sensitive to change with time are calcium, magnesium, iron, sulfate, and chloride. Iron concentrations range from less than 0.3 mg/L to as high as 49 mg/L but generally are 1 to 10 mg/L. In areas where rapid recharge occurs, shallow wells may have iron concentrations of less than 0.3 mg/L. Sulfate concentrations generally range from 0.5 to 50 mg/L but locally exceed 250 mg/L. The highest concentration detected was 1,900 mg/L. Chloride concentrations typically are less than 50 Mg/L. However, concentrations of chloride exceed 250 mg/L locally and are as high as 4,400 mg/L in a few areas. For this report, water with chloride concentrations greater than 250 mg/L is considered salty. The base of freshwater in the Red River Valley generally coincides with the base of the alluvium at depths of 80 to 150 feet. However, locally, the aquifer contains salty water, and the base of freshwater occurs within the aquifer; in parts of Rapides, Caddo, and Natchitoches Parishes, the base of freshwater extends below the alluvium. The largest occurrence of salty water is in Natchitoches Parish, with other smaller bodies occurring in Red River, Caddo, and Bossier Parishes. Water quality in the aquifer varies both areally and with depth; the quality also varies with time, depending on the quantity and chemical character of the recharge water.

Louisiana↗