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Press Release: Irrigation Causing Declines in the High Plains Aquifer

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Press Release: Groundwater Storage Losses Substantial Across Eight State Aquifer System

Report: Groundwater availability of the Mississippi embayment

Report: New tool to assess groundwater resources in the Mississippi embayment

Report: Selected approaches to estimate water-budget components of the High Plains, 1940-1949 and 2000-2009

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USGS Regional Groundwater Studies > Regional Groundwater Availability Studies

Regional Groundwater Availability Studies

Groundwater is among the Nation's most important natural resources. It provides half our drinking water and is essential to the vitality of agriculture and industry, as well as to the health of rivers, wetlands, and estuaries throughout the country. Large-scale development of groundwater resources with accompanying declines in groundwater levels and other effects of pumping has led to concerns about the future availability of groundwater to meet domestic, agricultural, industrial, and environmental needs. The challenges in determining groundwater availability are many.

The USGS Groundwater Resources Program (GWRP) is undertaking a series of regional groundwater availability studies to improve our understanding of groundwater availability in major aquifers across the Nation. Listed below are the completed and in-progress regional groundwater availability studies that implement the USGS strategy for conducting a national assessment as outlined in USGS Circular 1323:

• Current studies in progress
  • North Atlantic Coastal Plain Aquifer System
  • Floridan Aquifer System
  • High Plains Aquifers
  • Columbia Plateau Regional Aquifer System
• Completed studies
  • Mississippi Embayment Regional Aquifer Study
  • Great Basin Carbonate and Alluvial Aquifer System
  • Central Valley Aquifer
  • North and South Carolina Atlantic Coastal Plain Aquifer System
  • Denver Basin Aquifer
  • Middle Rio Grande Basin Study

Studies in Progress

North Atlantic Coastal Plain Aquifer System

Map of North Atlantic Coastal Plain Aquifer System study area.

The objectives of the North Atlantic Coastal Plain Groundwater Availability study are three fold: 1) quantify the current groundwater resources of one of the Nation's priority aquifer systems; 2) evaluate how this resource has changed over time; and 3) provide the tools needed to forecast how this aquifer system may respond to future human and environmental stresses. The focus of the North Atlantic Coastal Plain Groundwater Availability study is on improving fundamental knowledge of the water budget of this aquifer system, including the flows, storage, and use by humans and the environment. An improved quantitative understanding of the aquifer system's water budget not only provides key information about water quantity, but also is essential for assessments of water quality and ecosystem health.

Learn more about this study:

• Fact Sheet: Assessing groundwater availability in the Northern Atlantic Coastal Plain aquifer system
• Visit the study web site for a complete bibliography and more information

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Floridan Aquifer System

Map of Floridan Aquifer System study area.

The Floridan Aquifer System covers approximately 100,000 square miles in the southeastern United States in Florida and portions of Georgia, Alabama, Mississippi, and South Carolina. The overall objective for the current study is to assess the availability of water in the Floridan Aquifer System. Achieving this objective includes quantifying the groundwater resource by creating water budgets both spatially and temporally as well as evaluating the groundwater resource changes over time. Additionally, tools will be provided to assess the future impacts of humans and environmental changes (such as climate) on the Floridan Aquifer System and aid in designing groundwater monitoring networks.

Learn more about the outcomes of this study:

• Visit the study web site for a complete bibliography and to learn more.

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High Plains Aquifer

Map of High Plains Aquifer study area.

The High Plains groundwater availability study will quantify current groundwater resources, evaluate changes in those resources over time, and provide tools to forecast how those resources respond to stresses from future human and environmental uses. An improved quantitative understanding of the basin's water balance not only provides key information about water quantity but also is a fundamental basis for many analyses of water quality and ecosystem health.

Learn more about the outcomes of this study:

• Read an overview of the study: Assessing groundwater availability in the High Plains aquifer in parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming (Fact Sheet 2010–3008)
• Visit the study web site for a complete bibliography and to learn more.

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Columbia Plateau Regional Aquifer System

Map of Columbia Plateau Regional Aquifer System study area.

The Columbia Plateau Regional Aquifer System (CPRAS) covers over 50,000 square miles of eastern Oregon and Washington and western Idaho. The USGS has begun a study of the Columbia Plateau Regional Aquifer System to characterize the hydrologic status of the system, identify trends in groundwater storage and use, and quantify groundwater availability.

Learn more about the outcomes of this study:

• Watch a video about how the USGS uses 3D modeling to investigate groundwater in the Columbia Plateau Aquifer System.
• Explore the interactive 3D hydrogeologic model of the Columbia Plateau Regional Aquifer System.
• Visit the study web site for a complete bibliography and to learn more.

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Completed Studies

Mississippi Embayment Regional Aquifer Study

Map of Mississippi Embayment Regional Aquifer study area.

A groundwater flow model of the northern Mississippi embayment was developed to aid in answering questions about groundwater availability in a study area covering portions of seven states (Arkansas, Louisiana, Mississippi, Tennessee, Alabama, Missouri, and Kentucky).

Learn more about the outcomes of this study:

• Read the study summary report: The Mississippi Embayment Regional Aquifer Study (MERAS): Documentation of a groundwater-flow model constructed to assess water availability in the Mississippi Embayment (SIR 2009-5172)
• Visit the study web site for a complete bibliography and to learn more.

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Great Basin Carbonate and Alluvial Aquifer System

Map of Great Basin Carbonate and Alluvial Aquifer System study area.

The Great Basin Carbonate and Alluvial Aquifer System Water Availability Study quantified current groundwater resources, evaluated how those resources have changed over time, and developed tools to assess system responses to stresses from future human uses and climate variability.

Learn more about the outcomes of this study:

• Visit the study web site for a complete bibliography
• Read the study summary report: Water Availability and Use Pilot: A Multiscale Assessment in the U.S. Great Lakes Basin (USGS Professional Paper 1778)

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Central Valley Aquifer

Map of Central Valley study area.

For more than 50 years, California's Central Valley has been one of the most productive agricultural regions in the world. Large increases in population have resulted in greater competition for water within the Central Valley and statewide. The USGS assessed the groundwater availability of the Central Valley and quantified the groundwater resources using a variety of tools. The ultimate benefit of this assessment will be a better understanding of how the system responds to current and future human and environmental stresses that will prove useful to water managers in their decision making process related to this valuable resource.

Learn more about the outcomes of this study:

• Read an overview of the study: California's Central Valley groundwater study (Fact Sheet 2009-3057)
• Listen to a podcast about California's vast Central Valley groundwater system and the USGS study findings.
• Read the study summary report: Read the project summary report: Groundwater availability of the Central Valley Aquifer, California (Professional Paper 1766)
• Visit the study web site for a complete bibliography

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North and South Carolina Atlantic Coastal Plain Aquifer System

Map of North and South Carolina Atlantic Coastal Plain Aquifer System study area (Map source: PP 1773).

Increased groundwater withdrawals related to population growth and drought of the last few years have emphasized the need for more accurate, detailed information describing the groundwater resources in the Coastal Plain in North and South Carolina. In January 2004, the U.S. Geological Survey began a study to combine and update the Regional Aquifer System Analysis (RASA) models of North and South Carolina in order to improve the understanding of groundwater availability in the North and South Carolina Atlantic Coastal Plain aquifer system.

Learn more about the outcomes of this study:

• Read the study summary report: Groundwater Availability in the Atlantic Coastal Plain of North and South Carolina (Professional Paper 1773)
  
• Visit the study web site for a complete bibliography and to learn more.

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Denver Basin Aquifers

Map of Denver Basin Aquifers study area.

The Denver groundwater basin is an important and non-renewable source of water for municipal, industrial, and domestic uses in the Denver and Colorado Springs metropolitan areas. The USGS conducted a groundwater availability of the Denver Groundwater Basin to enhance our understanding of regional groundwater flow and aquifer storage, to evaluate current conditions, and to predict future conditions.

Learn more about the outcomes of this study:

• Visit the study web site for a complete bibliography and to learn more.
• Read the study summary report: Groundwater Availability of the Denver Basin Aquifer System, Colorado (USGS Professional Paper 1770)

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Middle Rio Grande Basin Study - Initial Proof of Concept Study

Map of Middle Rio Grande Basin study area (Map Source: Fact Sheet 088-02 [3MB PDF]).

The Santa Fe Group aquifer system in Central New Mexico is the main source of municipal water for the region. The USGS Middle Rio Grande Basin Study was a 6-year effort (1995-2001) to improve the understanding of the hydrology, geology, and land-surface characteristics of the Middle Rio Grande Basin in order to provide the scientific information needed for water-resources management. This initial proof of concept study was conducted prior to the development of the strategy outlined in Circular 1323 and served as as a precursor to current GWRP regional groundwater availability studies.

Learn more about the outcomes of this study:

• Read an overview of the study: Ground-water resources of the Middle Rio Grande Basin (Fact Sheet 088-02) [3MB PDF]
• Read the study summary report: Ground-water resources of the Middle Rio Grande Basin, New Mexico (Circular 1222)
• Visit the study web site for a complete bibliography and to learn more.

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