A brief tour of regional aquifers

Maps of major aquifers by rock/sediment type

Map of major aquifer types

Map of RASA units

Western Mountain Ranges

California's Central Valley (an alluvial basin)

Great Basin (more alluvial basins)

Columbia Lava Plateau

Dakota Sandstone (part of the Colorado Plateau)

High Plains Aquifer System

water level declines in the High Plains aquifer

Edwards Aquifer (within non-glaciated central region)

Piedmont and Blue Ridge Section

Crystalline PC & Northeastern Appalachians (Northeast and Superior Uplands)

Atlantic Coastal Plain

Southeastern Coastal Plain

Floridan Aquifer

Alluvial Valleys (distributed throughout the US)

Hawaii Lava tube

Puerto Rico Karst Features

Find lots more information via the Ground Water Atlas of the US

For a summary of Wisconsin's groundwater resources, the DNR has a good on-line publication