Official websites use .gov El Paso, however, has reduced its use of groundwater from the Hueco Bolson since 1989, and observation wells indicate that water levels have stabilized. The aquifer maps and reports undergo continual revision to reflect the latest information available. The surface extent, or outcrop, of each aquifer is the area in which the host formations are exposed at the land surface. Water levels in several counties in this region are very low due to over-pumping. 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. This system has been divided into three major water-producing components referred to as the Chicot, Evangeline, and Jasper aquifers. These aquifers consist of limestones, sands, clays, gravels, and conglomerates. Aquifer Code Name. Several agencies are investigating playa recharge and agricultural re-use projects over the aquifer. geline aquifers near Houston, Texas. 400--Carbonate-rock aquifers. The aquifer underlies an extensive area in south-central Texas extending along the Balcones fault zone from Kinney County eastward to San Antonio, and thence northeastward to Hays County. Groundwater encountered within this area is normally under unconfined, water-table conditions and is most susceptible to contamination. N or S, where N = aquifer, S = aquifer system, 3 digit number = rock type (4 digits used for "Other" to fill out the code), 100-- Sand and gravel aquifers200--Semiconsolidatedsand aquifers (not used)300--Sandstone aquifers400--Carbonate-rock aquifers500--Sandstone and carbonate-rock aquifers600--Igneous and metamorphic-rock aquifers9999--Areas that are not a national aquifer, 6 character identifier derived from the aquifer name using thecode derivation procedure also used for GWSI geohydrologic unit names. The pages below contain descriptionsand maps of these main aquifer types: These pages, formerly hosted at ourAquifer Basicswebsite,provide ageneral summary of information published in the Ground Water Atlas of the United States. The surficial aquifer in the Coastal Plain of these States should be included in the Northern Atlantic Coastal Plain aquifer system. Although the Carrizo-Wilcox Aquifer reaches 3,000 feet in thickness, the freshwater saturated thickness of the sands averages 670 feet. Sandstone aquifers can be highly productive and provide large volumes of water. Unconsolidated sand and gravel aquifers are characterized by intergranular porosity and all contain water primarily under unconfined, or water-table, conditions. The aquifer is comprised of the Twin Mountains, Glen Rose, Paluxy, Hosston, and Hensell formations. 1, Management plan data for Llano Estacado UWCD, Management Plan Information for Hemphill County UWCD, Management plan information for Mesquite GCD, Management plan information for High Plains UWCD #1, Management plan information for Hemphil County UWCD, Proportion of aquifer with groundwater conservation districts: 86 percent, Number of counties containing the aquifer: 49. The Texas Water Development Board (TWDB) specifically disclaims any and all liability for any claims or damages that may result from providing these data. 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. 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. The Wilcox Group and overlying Carrizo Sand form a hydrologically connected system of sand locally interbedded with clay, silt, lignite, and gravel. In Texas, the Panhandle is the most extensive region irrigated with groundwater. This dataset, published in 2003, contains the shallowest principal aquifers of the conterminous United States, Hawaii, Puerto Rico, and the U.S. Virgin Islands, portrayed as polygons. For study or mapping purposes, aquifers are often combined into aquifer systems. Aquifers shown on the 2003PrincipalAquifers map, with some additions, were used as the first National AquiferReferenceList in the USGSNational Water Information System(NWIS) in theAggregate Water Use Data System(AWUDS,database released in August 2001). General Information Letters and Private Letter Rulings, State Tax Automated Research (STAR) System, Historically Underutilized Business (HUB), Vendor Performance Tracking System (VPTS), Texas Procurement and Contract Management Guide, Minnie Stevens Piper Foundation College Compendium. Surficial deposits of glacial origin (New Jersey) should be included in Sand and gravel aquifers (glaciated regions). (March 2005). The Trinity Aquifer consists of basal Cretaceous-age Trinity Group formations extending through 61 counties from the Red River in North Texas to the Hill Country of Central Texas. The Ground Water Atlas of the United States is available onlineas anHTML website, asdownloadable PDFs, andoravailable for purchasethrough the USGS Store. Last fall while exploring for oil and gas deposits in southwest Texas, a driller instead found a huge freshwater deep aquifer. Please note that the maps do not show the entire extent of an aquifer, only itssubcropor outcrop area. in Texas. Located in the upper Pecos River Valley of West Texas, this aquifer, formerly called the Cenozoic Pecos Alluvium, extends through 12 counties. For Geophysical Well Log assistance contact. 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, Stratigraphic and Hydrogeologic Framework of Part of the Coastal Plain of Texas, Ground-Water Geology of Live Oak County, Texas, Ground-Water Resources of La Salle and McMullen Counties, Texas, Evaluation of Ground-Water Quality in Texas Counties Bordering the Rio Grande, Transmissivity, Hydraulic Conductivity, and Storativity of the Carrizo-Wilcox Aquifer in Texas, Ground-Water Resources of the Carrizo-Wilcox Aquifer in the Central Texas Region, Reconnaissance Investigation of the Ground-Water Resources of the Brazos River Basin, Texas, Ground-Water Resources of Grimes County, Texas, Ground-Water Resources of Brazos and Burleson Counties, Texas, Evaluation of Ground Water Resources in the Vicinity of the Cities of Henderson, Jacksonville, Kilgore, Lufkin, Nacogdoches, Rusk, and Tyler in East Texas, Geology and Ground-Water Resources of Uvalde County, Texas, Geology and Ground-Water Resources of Dimmit County, Texas, Ground-Water Geology of Bexar County, Texas, Ground-Water Geology of Wilson County, Texas, Ground-Water Resources of Guadalupe County, Texas, Ground-Water Resources of Caldwell County, Texas, Ground-Water Resources of Gonzales County, Texas, Availability and Quality of Ground Water in Leon County, Texas, Ground-Water Conditions in Anderson, Cherokee, Freestone, and Henderson Counties, Texas, Ground-Water Resources of Bastrop County, Texas, Ground-Water Resources of Lee County, Texas, Ground-Water Resources of Navarro County, Texas, A Digital Model of the Carrizo-Wilcox Aquifer Within the Colorado River Basin of Texas (cross-section figures, Availability and Quality of Ground Water in Smith County, Texas, Ground-Water Resources of Camp, Franklin, Morris, and Titus Counties, Texas, Ground-Water Resources of Houston County, Texas, Ground-Water Resources of Harrison County, Texas, Ground-Water Resources of Sabine and San Augustine Counties, Texas, Ground-Water Resources of Wood County, Texas, Ground-Water Resources of Gregg and Upshur Counties, Texas, Ground-Water Conditions in Angelina and Nacogdoches Counties, Texas, Ground-Water Resources of Rusk County, Texas, Geology and Ground-Water Resources of Medina County, Texas, Ground-Water Resources of Atascosa and Frio Counties, Texas, Ground-Water Resources of Rains and Van Zandt Counties, Texas, Availability and Quality of Ground Water in Fayette County, Texas, Depth to aquifer layers for the Carrizo-Wilcox, Queen City, and Sparta aquifers in McMullen County, Management plan information for Post Oak Savannah GCD, Predictive simulations for the Carrizo-Wilcox, Queen City, Sparta, and Yegua-Jackson aquifers in Groundwater Management Area 11, Management plan information for Wintergarden GCD, Analysis of pumping information for the Carrizo-Wilcox, Queen City, and Sparta aquifers in Groundwater Management Area 12, Management plan information for Uvalde County UWCD, Management plan information for Evergreen UWCD, Management plan information for Lost Pines GCD, Management plan information for Brazos Valley GCD, Management plan information for Live Oak UWCD, Predictive simulations for the Carrizo-Wilcox, Queen City, and Sparta aquifers in Groundwater Management Area 13, Management plan information for Medina County GCD, Management plan information for Neches & Trinity Valleys GCD, Management plan information for Rusk County GCD, Management plan information for Bluebonnet GCD, Predictive simulation for the Carrizo and Middle Wilcox aquifers in Anderson County, Management plan information for Mid-East Texas GCD, Management plan information for Panola County GCD, Management plan information for Pineywoods GCD, Predictive simulation for the Carrizo-Wilcox, Queen City, and Sparta aquifers in Groundwater Management Area 13, Average drawdowns by county for GAM Runs 08-41, 08-42, and 08-43 in Groundwater Management Area 13, Management plan information for Pecan Valley GCD, Management plan information for Fayette County GCD, Management plan information for McMullen GCD, Management plan information for Guadalupe GCD, Predictive simulation for the Carrizo-Wilcox, Queen City, and Sparta aquifers in Groundwater Management Area 11, Management plan information for Anderson County UWCD, Average drawdowns for the Carrizo-Wilcox, Queen City, and Sparta aquifers based on the analysis completed in GAM Run 06-029, Predictive simulation for the Carrizo-Wilcox, Queen City, and Sparta aquifers in Fayette County GCD, Management plan information for Plum Creek Conservation District, Predictive simulation for the Carrizo-Wilcox, Queen City, and Sparta aquifers in Mid-East Texas GCD, Predictive simulation for the Carrizo-Wilcox Aquifer in Rusk County GCD, Impacts of pumping increases in the in the Carrizo-Wilcox Aquifer near Jewett, Texas (Leon County), Recharge information for the Carrizo-Wilcox, Edwards-Trinity (Plateau) and Trinity aquifers in Uvalde County, Recharge information for the Carrizo-Wilcox and Trinity aquifers in Medina County, Water level information for the Gulf Coast, Carrizo-Wilcox, Queen City, and Sparta aquifers in Live Oak County, Water budget information for the Carrizo-Wilcox, Queen City, and Sparta aquifers in Bee, Live Oak, and McMullen counties, Post Oak Savannah GCD, water budget, water levels, drawdown through 2050, 2002 State Water Plan pumping summary, and interaction with the Brazos River Alluvium Aquifer, Statistical summary and map of storage coefficient for the Simsboro Aquifer in Burleson County, Statistical summary and map of transmissivity of the Simsboro Aquifer in Burleson County, Recharge amounts and maximum pumping needed to maintain current water levels in Mid-East Texas GCD, Aquifer recharge values for Neches and Trinity Valleys GCD, Recharge amounts and maximum pumping that allows maintaining current water levels in Mid-East Texas GCD, Predictive run using Region C provided pumping, Predictive run using pumping data provided by Post Oak Savannah GCD, Water budget and total storage above 4000 depth in Evergreen UWCD, Total water availability in Henderson, Navarro, and Freestone counties, Recharge information and total storage above 3000 feet using a predictive simulation in Milam and Burleson counties, Recharge and total storage data for the Carrizo-Wilcox, Queen City, Sparta, and Gulf Coast aquifers in Fayette County GCD, Water budget, storage, and water level drawdown for the Carrizo-Wilcox Aquifer and recharge information for the Gulf Coast Aquifer in Bee GCD, Water availability for the Carrizo-Wilcox Aquifer in Henderson, Navarro, and Freestone counties, 20102030 water level drawdowns for the Carrizo-Wilcox Aquifer in Rusk, Smith, and Gregg counties, Water budget, storage, and drawdown in 2050 for the Trinity (Hill Country) and Carrizo-Wilcox aquifers in Medina County GCD, Recharge, available storage, estimated and projected declines for the Carrizo-Wilcox Aquifer in Pineywoods GCD, Estimated drawdown under assumed future pumping for the Carrizo-Wilcox, Queen City, and Sparta aquifers in Groundwater Management Area 13, Drawdown maps and water budget for GAM run 11-007, Predictive simulations for the Carrizo-Wilcox, Queen City, and Sparta aquifers in Groundwater Management Area 11, Management plan information for Gonzales County UWCD, Management plan data for Panola County GCD, Management plan data for Fayette County GCD, GAM run - Total Estimated Recoverable Storage, Total Estimated Recoverable Storage for aquifers in Groundwater Management Area 16, Management Plan data for Gonzales County UWCD, Management plan data for Neches & Trinity Valleys GCD, Management plan data for Mid-East Texas GCD, GAM task - Total Estimated Recoverable Storage, Total Estimated Recoverable Storage for aquifers in Groundwater Management Area 13, Total Estimated Recoverable Storage for aquifers in Groundwater Management Area 15, Management Plan data for Brazos Valley GCD, Total Estimated Recoverable Storage for aquifers in Groundwater Management Area 11, Total Estimated Recoverable Storage for aquifers in Groundwater Management Area 12, Total Estimated Recoverable Storage for aquifers in Groundwater Management Area 14, Predictive run using pumping distribution provided by Post Oak Savannah GCD, Management plan data for Medina County GCD, Management Plan data for Uvalde County UWCD, Management Plan data for Wintergarden GCD, Management plan information for Neches and Trinity Valleys GCD, Proportion of aquifer with groundwater conservation districts: 65 percent, Number of counties containing the aquifer: 66. It is part of the U.S. Geological Survey National Water Information System. In general, groundwater is fresh but very hard in the outcrop of the aquifer. The Texas Water Development Board recognizes and names 15 such aquifers. Hydrogeologic unit boundaries (framework) and groundwater recharge data. 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). The lower, more permeable part of the aquifer produces the greatest amount of groundwater. Located west of the Franklin Mountains, the Mesilla Bolson reaches up to 2,000 feet in thickness and contains three separate water-producing zones. This is one in a series of reports the Comptroller has prepared on water in Texas. Texas State Historical Association (TSHA). An official website of the United States government. The largest area of groundwater-level decline in the Ogallala aquifer was found in Gaines County to the southwest of Denver City, Texas. Extending from the Rio Grande in South Texas northeastward into Arkansas and Louisiana, the Carrizo-Wilcox aquifer provides water to all or parts of 66 counties. Researchers have identified a previously undiscovered aquifer in southwest Texas. Edwards (Balcones Fault Zone) (San Antonio-oriented) Search and browse the first 148 years of the Texas Almanac, hosted on the UNT Portal to Texas History. County-- select one or more . Water levels in the Trinity Aquifer, the county's main source of groundwater, plunged. storage and recovery facility Individual accumulations vary greatly in thickness, but most of the Seymour is less than 100 feet. 9999--Areas that are not a national aquifer. Conservation districts are promoting more-efficient irrigation techniques, and market-based, voluntary transfers of unused agricultural water rights to municipal uses are more common. Irrigation, mainly in the northwestern portion of the region, accounted for about 79 percent of total aquifer use in 2008 and has resulted in significant water-level declines in Glasscock and Reagan counties. The Trinity Aquifer consists of basal Cretaceous-age Trinity Group formations extending through 61 counties from the Red River in North Texas to the Hill Country of Central Texas. Years of heavy pumpage have caused significant water-level declines in portions of the aquifer. 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. It is absent in a broad area extending from the north central portion of the county continuing to the south, southwest part of Gillespie County. Center the map where you want the center of your print, enter a title in the textbox and choose a page size for your print using the drop down. Larry French, director of the groundwater division at the Texas Water Development Board, spoke to Texas Standard about its potential . Get your free copy of the 20202021 Texas Almanac eBook. The availability of this water is critical to the economy of the region, as approximately 95 percent of groundwater pumped is used for irrigated agriculture. It consists of the Hooper, Simsboro, and Calvert Bluff formations of the Wilcox Group and the overlying Carrizo Formation of the Claiborne Group. The Hickory aquifer occurs in parts of 19 counties in the Llano Uplift region of Central Texas. 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