1700 North Congress Avenue, Austin, TX 78701TEL: 512-463-7847 / FAX: 512-475-2053, Asset Management Program for Small Systems, State Water Implementation Fund for Texas (SWIFT), Guidance & References for Online Loan Application, State Water Implementation Fund for Texas, 6th Planning Cycle Information (2026 RWPs), 2021 Regional Water Plans & Previous Plans, Regional Water Planning Data Entry Application (RWP22) Training, District Information (O-Z and Other Districts), Extended Naturalize Flow and Reservoir Evaporation, Flood Planning Useful Links and Resources, Drought Response and Financial Assistance, Water Conservation Plan ~ Utility Profile, Historical Water Loss Audit and Conservation Annual Report Data, Industrial, Commercial & Institutional (ICI), Brackish Resources Aquifer Characterization System, Notice of Nondiscrimination and Reasonable Accommodation, Texas Natural Resources Information System (TNRIS), Texas Water Infrastructure Coordination Committee (TWICC), Texas Aquifers Study: Groundwater Quantity, Quality, Flow, and Contributions to Surface Water, An Investigation of Clouds and Precipitation for the Texas High Plains, Quantity and Chemical Quality of Low Flow in the Prairie Dog Town Fork Red River near Wayside, Texas, February 6-9,1968, Evaluating the Ground-Water Resources of the High Plains of Texas, Volumes 1-4, The High Plains Aquifer System of Texas, 1980 to 1990 - Overview and Projections, Evaluation of Ground-Water Resources in Dallam County, Texas, Evaluation of Enhanced Recharge Potential to the Ogallala Aquifer in the Brazos River Basin, Hale County, Texas, Updated Water-Quality Evaluation of the Ogallala Aquifer, Including Selected Metallic and Non-Metallic Inorganic Constituents, Studies of Playa Lakes in the High Plains of Texas, Geology and Ground-Water Resources of Hale County, Texas, Ground-Water Resources of Gaines County, Texas, Reconnaissance Investigation of the Ground-Water Resources of the Brazos River Basin, Texas, Conference Proceedings: Aquifers of the Edwards Plateau, Water-Quality Evaluation of the Ogallala Aquifer, Texas, Evaluation of Ground-Water Resources in Briscoe, Hale, and Swisher Counties, Texas, Evaluation of Ground-Water Resources in the Southern High Plains of Texas, Ground-Water Resources of Collingsworth County, Texas, Ground-Water Resources of Hall and Eastern Briscoe Counties, Texas, Water-Level Changes in the High Plains Aquifer of Texas, 1980-1990, Management plan information for Hemphill County UWCD, Management plan information for High Plains UWCD No. Spaces in crystalline rocks are microscopically small, few, and generally unconnected. the largest aquifer Please note that the maps do not show the entire extent of an aquifer, only itssubcropor outcrop area. These aquifers consist of limestones, sands, clays, gravels, and conglomerates. There are nine major aquifers and 22 minor aquifers that supply groundwater for municipal and irrigation needs throughout the state. This aquifer underlies the Edwards Plateau, extending through 40 counties from the Hill Country of Central Texas westward to the Trans-Pecos region. The largest area of groundwater-level decline in the Ogallala aquifer was found in Gaines County to the southwest of Denver City, Texas. Some water-bearing formations dip below the surface and are covered by other formations. However, some individual aquifers serve mostly municipal purposes. This is one in a series of reports the Comptroller has prepared on water in Texas. In 2008, irrigation accounted for 43 percent of water pumped from the aquifer, and municipal supply accounted for 47 percent. Elsewhere, the aquifer supplies fresh but hard water for municipal, domestic, and livestock use. Years of heavy pumpage have caused significant water-level declines in portions of the aquifer. About 55 percent of all water used in Texas was sourced through aquifers in 2019. Each PA was sampled across its lateral extent using an equal-area grid, typically with 60 wells. These aquifers are located in El Paso and Hudspeth counties in far West Texas and occur in Tertiary and Quaternary basin-fill deposits that extend northward into New Mexico and westward into Mexico. For an overview ofprincipalaquifers:The principal water-yielding aquifers of North America can be grouped into five types by rock type and location: unconsolidated and semiconsolidated sand and gravel aquifers, sandstone aquifers, carbonate-rock aquifers, aquifers in interbedded sandstone and carbonate rocks, and aquifers in igneous and metamorphic rocks. This dataset, published in 2002, represents the extent of the alluvial and glacial aquifers north of the southern-most line of glaciation. Such sites will not be retrieved using this search criteria. The Ogallala Aquifer is the largest aquifer in the United States and is a major aquifer of Texas underlying much of the High Plains region. Refer to the metadata for a complete description of the files and how they were generated. The aquifer consists of sand, gravel, clay, and silt and has a maximum thickness of 800 feet. Map of major and minor aquifers in Texas. The desired future conditions provide the foundation for estimating the amount of groundwater available to the region. (Note that the National Aquifer Code uses a different numeric component than the geohydrologic unit names.). A lock () or https:// means youve safely connected to the .gov website. (February 2005), Valley and Ridge carbonate-rock aquifers were removed:these now should be included in Valley and Ridge aquifers. Total ground-water withdrawals were 76,500 million gallons per day, or 85,800 thousand acre-feet per year for these three uses. Texas State Historical Association (TSHA). 6 character identifier derived from the aquifer name using the code derivation procedure also used for GWSI geohydrologic unit names. It consists of the Hooper, Simsboro, and Calvert Bluff formations of the Wilcox Group and the overlying Carrizo Formation of the Claiborne Group. The characterization of the state's groundwater resources and the development of the maps depicting these aquifers have been accomplished by many staff members of the TWDB over many years. Proceeds benefit education in TX. geline aquifers near Houston, Texas. Texas Water Development Board works best with JavaScript enabled, 1700 North Congress Avenue, Austin, TX 78701TEL: 512-463-7847 / FAX: 512-475-2053, Asset Management Program for Small Systems, State Water Implementation Fund for Texas (SWIFT), Guidance & References for Online Loan Application, State Water Implementation Fund for Texas, 6th Planning Cycle Information (2026 RWPs), 2021 Regional Water Plans & Previous Plans, Regional Water Planning Data Entry Application (RWP22) Training, District Information (O-Z and Other Districts), Extended Naturalize Flow and Reservoir Evaporation, Flood Planning Useful Links and Resources, Drought Response and Financial Assistance, Water Conservation Plan ~ Utility Profile, Historical Water Loss Audit and Conservation Annual Report Data, Industrial, Commercial & Institutional (ICI), Brackish Resources Aquifer Characterization System, Notice of Nondiscrimination and Reasonable Accommodation, Texas Natural Resources Information System (TNRIS), Texas Water Infrastructure Coordination Committee (TWICC). Texas has three ASR systems. The Texas Water Development Board (TWDB) specifically disclaims any and all liability for any claims or damages that may result from providing these data. El Paso, however, has reduced its use of groundwater from the Hueco Bolson since 1989, and observation wells indicate that water levels have stabilized. In cooperation with Harris-Galveston Subsidence District, the City of Houston, Fort Bend County Subsidence District, Lone Star Groundwater Conservation District, and Brazoria County Groundwater Conservation District, the U.S. Geological Survey Texas Water Science Center Gulf Coast . Revisions to the reference list since it was first used by NWIS: Northern Great Plains aquifer system was removed:this umbrella term includes four national aquifers but is not considered a national aquifer itself. Conservation districts are promoting more-efficient irrigation techniques, and market-based, voluntary transfers of unused agricultural water rights to municipal uses are more common. The aquifer is primarily composed of sand locally interbedded with gravel, silt, clay, and lignite. And so we've seen water levels drop in those aquifers and we've seen spring flows as a response also drop. Aquifers play a major role in providing water to many parts of Texas. Eastward-flowing streams during the Quaternary Period deposited discontinuous beds of poorly sorted gravel, sand, silt, and clay that were later dissected by erosion, resulting in the isolated remnants of the formation. Texas Water Development Board works best with JavaScript enabled. In 1993, the Edwards Aquifer Authority (EAA) was created by the legislature to regulate aquifer pumpage to benefit all users from Uvalde County through a portion of Hays County. Below are other webpages associated with principal aquifers. In 2008, about 72 percent of pumpage from the aquifer was for municipal use. They are grouped into four categories: basin-fill, blanket sand and gravel, glacial-deposit, and stream-valley aquifers. Secure .gov websites use HTTPS Search and browse the first 148 years of the Texas Almanac, hosted on the UNT Portal to Texas History. Volcanic-rock aquifers have a wide range of chemical, mineralogic, structural, and hydraulic properties Aquifer maps often include large-to-small areas that are designated "minor aquifer," "not a principal aquifer," or "confining unit. These are usually areas are underlain by low-permeability deposits and rocks, unsaturated materials, or aquifers that supply little water because they are of local extent, poorly permeable, or both. 1, Management plan information for Gateway GCD, Predictive simulations for the Ogallala and Edwards-Trinity (High Plains) aquifers in Groundwater Management Area 7, Predictive simulation for the Ogallala and Edwards-Trinity (High Plains) aquifers in Groundwater Management Area 2, Management plan information for Llano Estacado UWCD, Management plan information for Garza County UWCD, Management plan information for Sandy Land UWCD, Predictive simulations for the Ogallala Aquifer in Groundwater Management Area 1, Predictive simulations for the Ogallala Aquifer in Groundwater Management Area2, Initial and final water volumes for the simulations presented in GAM Run 08-085, Predictive simulation for the Ogallala Aquifer in Groundwater Management Area 2, Management plan information for Garza County Underground and FWCD, Management plan information for Mesa UWCD, Management plan information for Permian Basin UWCD, Management plan information for Panhandle GCD, Management plan information for Glasscock GCD, Management plan information for South Plains UWCD, Predictive simulations for the Ogallala Aquifer in Groundwater Management Area 2, Volume calculations for the Ogallala Aquifer in Groundwater Management Area 1, Volume calculations and pump rates for the Ogallala Aquifer in Groundwater Management Area 1, Analysis using specified depletions for districts in Groundwater Management Area 1, Management plan information for North Plains GCD, Water budget and GIS information for the Ogallala Aquifer in Hemphill County, Saturated thickness shapefile for the Ogallala Aquifer in Hemphill County, Saturated thickness shapefile for the Ogallala Aquifer in Hemphill County (zip file), Saturated thickness maps for the Ogallala Aquifer in Region A, Groundwater volumes for the Ogallala Aquifer in Randall and Oldham counties, Comparison of groundwater volumes between GR 04-13 and GR 05-09 for the Ogallala Aquifer in Region A, Saturated thickness, groundwater volumes, and water level maps for the Ogallala Aquifer in Region A, Various pumping scenarios for the Ogallala Aquifer in Hemphill County, Water budget and volume of water in storage for Hemphill County using a predictive simulation, Saturated thickness map for the Ogallala (north) Aquifer, Recharge rates per model cell in the Ogallala (north) Aquifer GAM, Groundwater in storage for Region A using a 1.25% annual depletion rate, Hydraulic conductivity data for the Ogallala Aquifer GAMs, Volumetric calculations for all counties in Llano Estacado Regional Water Planning Group, Groundwater volume in each county-basin zone of Region O (Llano Estacado), Determine pumping rate equivalent to a volume depletion rate of no more than 1% per year, Predictive run with Region O provided increase in irrigation pumping, Water table declines and water budget in South Plains UWCD, Groundwater volume in each county-basin zone of Region O (Llano Estacado) Clarification memo, Water budget and total available storage for the Ogallala Aquifer in Permian Basin UWCD, Volume of water in storage and recharge information for the Ogallala Aquifer in High Plains UWCD No. The information was collected by the U.S. Geological Survey and other agencies during the course of many years of study. Water quality generally ranges from fresh to slightly saline. Geology, Major and Minor Aquifers, BRACS Study Areas, Regional Water Planning Areas, Groundwater Management Areas, Groundwater Conservation Districts, River Basins, Counties, 7.5' United State Geological Survey Grid, 2.5' State Grid, Latitude, Longitude, and Land Elevation. (March 2005). The effects of over-pumping removing more groundwater than what is entering an aquifer pose continual challenges for aquifer managers across the state. Select the area, distance or location tool below. Although its primary use is for municipalities, it is also used for irrigation, livestock, and other domestic purposes. Freshwater saturated thickness averages 95 feet. Aquifers are vital to the states economy and environment, highlighting the need for their proper management and conservation. The Ogallala aquifer extends through 48 counties of the Texas Panhandle and is the southernmost extension of the largest aquifer (High Plains aquifer) in North America. Parts of the aquifer in the Winter Garden area and portions of Brazos County are slightly to moderately saline, with total dissolved solids ranging from 1,000 to 7,000 milligrams per liter. Throughout most of its extent in Texas, the aquifer yields fresh to slightly saline water that is used mainly for irrigation in the Winter Garden District of South Texas, and for public supply and industrial use in Central and Northeast Texas. It is composed of several smaller aquifers contained within the Trinity Group. The Carrizo-Wilcox Aquifer has long been utilized by private well owners, municipalities, agricultural producers and industry. The U.S. Geological Survey prepared this dataset in cooperation with the Harris-Galveston Subsidence District, City of Houston, Fort Bend Subsidence District, Lone Star Groundwater Conservation District, and Brazoria County Groun Elsewhere, water from the Trinity Aquifer is used primarily for municipal and domestic supply. Page Contact Information: Texas Water Data Maintainer Page Last Modified: 2023-02-25 01:14:50 EST Natural salt pollution in the upper reaches of the Red and Brazos river basins precludes the full utilization of these water resources. U.S. Geological Survey 505 Ferguson Lane Austin, Texas 78754-4501 The Edwards and Trinity aquifers are classified as major aquifers by the Texas Water Development Board and are major sources of water in south-central Texas, where Hays County is located. To learn more, visit theNational Aquifer Code Reference List. In 2008, municipal uses accounted for 62 percent and irrigation accounted for 25 percent of the total pumpage from the aquifer. County-- select one or more . Presented by The EAA has an active program to educate the public on water conservation and also operates several active groundwater recharge sites. The Wilcox Group and overlying Carrizo Sand form a hydrologically connected system of sand locally interbedded with clay, silt, lignite, and gravel. Aquifer Code Name. Well, in Central Texas, and particularly the Edwards Aquifer, it's an aquifer that has a lot of caves in it and fractures. This aquifer consists of isolated areas of alluvium found in parts of 25 north-central and Panhandle counties in the upper Red River and Brazos River basins. The Ogallala Formation of late Miocene to early Pliocene age consists of heterogeneous sequen-ces of coarse-grained sand and gravel in the lower part, grading upward into clay, silt, and fine sand. The surface extent, or outcrop, of each aquifer is the area in which the host formations are exposed at the land surface. Aquifers are identified by a geohydrologic unit code-a three-digit number related to the age of the formation, followed by a 4 or 5 character abbreviation for the geologic unit or aquifer name. Groundwater also supplies about 35 percent of the states municipal needs. Texas Water Development Board works best with JavaScript enabled. Browse our curated list of helpful links for students and researchers. Beets will help keep Bexar County roads from freezing this week. National Geographic Information Systems (GIS) layer of SSAs Information on sole source aquifers (SSAs) is widely used in assessments under the National Environmental Policy Act and at the state and local level. Water Systems An official website of the United States government. About 60 percent of the approximately 16 million acre-feet of water used yearly in Texas is derived from underground formations that make up 9 major and 22 minor aquifers. Until recently, San Antonio was one of the largest cities in the world that relied solely on a single groundwater source for its municipal supply. It consists of sandstone and limestone formations of the Trinity formations, and limestones and dolomites of the Edwards and associated limestone formations. In 2008, 72 percent of groundwater pumped from the aquifer was used for irrigation, and the rest is withdrawn for industrial uses, power supply, and municipal use. Entriesinitalicsare no longer valid.To learn more about a specific aquifer, visit the Principal Aquifers websitefor an overview, or access more extensive information from theGround Water Atlas of the United States. The Ogallala Aquifer provides significantly more water for users than any other aquifer in the state. Water Tour | Aquifers Overview | Print Snapshot (PDF). Because of the scar-city of measurable water-table wells, depth to the water table below land surface was estimated using Most water from aquifers is used for irrigation. Below are publications associated with national aquifers. Some of these declines have resulted in significant land-surface subsidence, particularly in the Houston-Galveston area. A .gov website belongs to an official government organization in the United States. Individual accumulations vary greatly in thickness, but most of the Seymour is less than 100 feet. Municpal water use in 2008 accounted for 87 percent of total use from the Hueco-Mesilla Bolson. The aquifer also feeds several well-known recreational springs and underlies some of Texas most environmentally sensitive areas. In 2019, more than 90 percent of the water pumped from the Ogallala was used for irrigation, while more than 90 percent of the Hueco-Mesilla pumpage served municipal purposes. In most places where these two rock types are interbedded, the carbonate rocks yield much more water than the sandstone. Additional aquifer data through the USGS web app Excessive pumping has lowered the water level, particularly in the artesian portion of the Winter Garden District of Atascosa, Dimmit, Frio, LaSalle, and Zavala counties and in the municipal and industrial areas of Angelina, Nacogdoches, and Smith counties. Summary The Carrizo-Wilcox Aquifer is a major aquifer extending from the Louisiana border to the border of Mexico in a wide band adjacent to and northwest of the Gulf Coast Aquifer. Groundwater movement is generally toward the southeast. The San Antonio River Authority also has a number of flood-control structures that effectively recharge the aquifer. These data delineate the areal extent of the alluvial and glacial aquifers as defined in The Ground Water Atlas of The United States. Texas Water Development Board works best with JavaScript enabled. 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