New in GWRP

• Regional Groundwater Studies
  • Groundwater Availability in the United States
• Water Availability Pilot
  • Consumptive water use coefficients for Great Lakes Basin
• Groundwater & the Environment
  • Groundwater Recharge in Southwestern US
• Methods & Modeling
  • SEAWAT v4--Simulation of 3D variable-density ground--water flow and transport
• Data & Information
  • Water-Level changes in aquifers of the Atlantic Coastal Plain, predevelopment to 2000

USGS in Your State

USGS Water Science Centers are located in each state.

Groundwater Recharge

Groundwater recharge is a critical part of the overall water budget and is one of the most difficult components to quantify. The mapping of the spatial and temporal variability of recharge remains a topic of great interest. Improved knowledge of this variability would help water managers to better assess water availability and protect vulnerable aquifers under stresses from expanding urbanization or drought. Recharge estimates should be detailed enough to resolve local variability while also providing accurate regional values needed to manage a regional groundwoater system.

The Groundwater Resources Program supports activities that develop a better understanding of recharge processes at local scales and also develop capabilities to estimate recharge at the scale of regional aquifer systems. Recent examples of such investigations include:

• Climate Variability Effects
• Ground-Water Age Dating & Recharge
• Chloride Mass Balance in Streams to Estimate Recharge