The Colorado River Basin has lost twice as much groundwater since 2003 as water taken out of its reservoirs, according to a ...

To see evidence of the Columbia River’s ancient past, you might not need to visit the river at all. In a roadcut just south of Granger, Yakima County, 10 million-year-old evidence is in plain view.

As the Colorado River's reservoirs have declined, even larger amounts of groundwater have been drained from aquifers. Using ...

View the methodology report for further details. Regional studies–more detailed analysis undertaken by various State and regional agencies using a range of different approaches including field work, ...