Evapotranspiration

Declining snow cover is playing a key role in decreasing the flow of the Colorado River, “the lifeblood of the Southwest,” by enabling increased evaporation. As the warming continues, increasingly severe water shortages are expected.

For 43 years, the Shingobee Headwaters Aquatic Ecosystems Project (SHAEP) brought together scientists from the USGS along with students and professors from universities in Minnesota, North Dakota, Wisconsin, and California to study the physical, chemical, and biological processes of lakes, wetlands, and streams at local and watershed scales. In early 2022, The University of Minnesota and Bemidji...

The USGS is evaluating the integration of small unoccupied aircraft systems – sUAS or "drones" – into USGS hydrogeophysical studies. The following projects are part of a Water Resources Mission Area demonstration and evaluation effort in collaboration with USGS Water Science Centers (WSCs) starting in June 2018.

The USGS has estimated water use for the United States every 5 years since 1950. Estimates are provided for groundwater and surface-water sources, for fresh and saline water quality, and by sector or category of use. Estimates have been made at the State level since 1950, and at the county level since 1985. Water-use estimates by watershed were made from 1950 through 1995, first at the water...

Irrigation water use includes water that is applied by an irrigation system to sustain plant growth in agricultural and horticultural practices. Irrigation also includes water that is used for pre-irrigation, frost protection, chemical application, weed control, field preparation, crop cooling, harvesting, dust suppression, and leaching salts from the root zone. Estimates of irrigation withdrawals...

USGS is undertaking a 3-year study of water use, availability, and change in the Upper Rio Grande Basin. This study area runs 670 miles from its headwaters in Colorado through New Mexico and northern Mexico to Texas, and will compile existing information and add new scientific data and interpretation to help stakeholders face current and future water issues.

All water naturally contains dissolved solids that can make it "brackish" or distastefully salty. The amount of freshwater for drinking-water, agricultural, industrial, and environmental needs has declined in many areas and has led to concerns about future availability. The USGS conducted a national assessment of brackish aquifers that could supplement or replace freshwater sources.

As one of several Focus Area Studies within the USGS National Water Census (NWC), the USGS has completed a 3-year study of water availability and use in the Colorado River Basin.