Researchers have created the most detailed map yet of groundwater across the United States, offering a clearer picture of how much fresh water lies beneath our feet. Scientists from Princeton University and the University of Arizona combined more than a million groundwater measurements with artificial intelligence to map water table depth across the country at a resolution of about 30 meters.
Their findings estimate the U.S. holds about 306,000 cubic kilometers of groundwater — more than 13 times the volume of the Great Lakes. The study also identified previously unknown pockets of shallow groundwater, which are especially important for farming, drinking water, and local ecosystems.
Researchers say the map could help communities make better decisions about irrigation, conservation, and water infrastructure — especially in regions facing drought or contamination risks. The data is now publicly available and could guide water planning at both local and national levels.
