U.S. Geological Survey - National Water Information System
The National Water Information System (NWIS) provides access to hydrologic data such as flows, water levels, groundwater levels, and water quality collected at multiple sites in all 50 states of the United States, the District of Columbia, Puerto Rico, the Virgin Islands, Guam, American Samoa, and the Commonwealth of the Northern Mariana Islands.
Number of devices and sensors
13449 devices 28965 sensors
Most U.S. Geological Survey (USGS) information is in the public domain and may be used without restriction. When using information from USGS information products, publications, or websites, the USGS requests appropriate attribution.