Organization and Data National and State

The US Geological Survey (USGS) department of water resources is the best source for national water data. Their database, National Water Information System, contains real time and historical data on surface water, groundwater and water quality at both a national level and disaggregated by state. In addition to this database they maintain an extensive list of links to outside data sources.

The US Army Corp of Engineers is responsible for the development and construction of most of the water infrastructure in the US. Their Southwest Division is the branch that works on Californian infrastructure. There is a searchable library of publications and reports available dating to the 50's.

The US Army Corp of Engineers is responsible for the development and construction of most of the water infrastructure in the US. Their Southwest Division is the branch that works on Californian infrastructure. There is a searchable library of publications and reports available dating to the 50's.

The US Bureau of Reclamation manages much of the large water infrastructure in the western US, including many of the dams and reservoirs. It is the largest wholesaler of water and the second largest producer of hydroelectric power. USBR has a database on dams, reservoirs, projects and power plants, as well as regional and state maps.

The US Environmental Protection Agency (EPA) develops and enforces national environmental regulation in the US.  The EPA's Office of Water is the branch that handles water related regulations.  The EPA's water database contains data and measurements primarily relating to water quality.

The Center for Disease Control (CDC) is concerned with how water affects health. The CDC's water quality division addresses water quality and water borne diseases.  Their data and statistics website has data pertaining to water in relation to health.

The National Weather Service (NWS) is a branch of NOAA that records and forecast weather conditions. They maintain data on precipitation and snowfall, river conditions and floods.  NWS and NOAA generate an astonishing amount of data. For example, the National Climate Data Center is one gateway to historical climate data.

Water-data.com claims to be the most complete source of water data for Colorado River. They have a variety of graphs and tables pertaining to the reservoirs that the Colorado River feeds into.

California Specific

The Californian Department of Water Resources (DWR) is the state agency in charge of managing California water. Their Data Resource Center carries links to a huge number of state-wide and some regional databases. This is an excellent place to start looking for data on California's water supply. One of the best resources that the DWR provides is the California Data Exchange Center (CDEC). The CDEC operates an extensive hydrologic data collection network including automatic snow reporting gauges for the Cooperative Snow Surveys Program and precipitation and river stage sensors for flood forecasting.

The Metropolitan Water District supplies most ofsouthern California with its water, including Los Angeles, Riverside and San Diego. Their operations database has statistics on historical water rates, volume of sales disaggregated by region and end user, current reservoir levels, and meter usage. MWD archives their annual reports and financial reports which include data on water rates and budgets. Virtually all of California's water is purchased from two sources. The State Water Project, a project of the California DWR, and the Colorado River Basin Project a project of the U.S. Bureau of Reclamation.