Essential Tools and Products

To manage our water resources effectively, we need to understand how much water is available and its usefulness. The USGS monitors the nation’s water resources through various national observing networks that use a range of technologies and methods to assess real-time water conditions and predict future changes in water availability for human and ecological uses.

The USGS Water Resources Mission Area is assessing how much water is available for human and ecological needs in the United States and identifying where and when the Nation may have challenges meeting its demand for water.

The National Water Availability Assessment Data Companion (NWDC) delivers model-based estimates of water supply and demand.

As of October 2024, the USGS Groundwater and Streamflow Information Program supports the collection and (or) delivery of both streamflow and water-level information at 8,705 sites and water-level information alone at 3,460 additional sites. The data are served online—most in near real-time—to meet many diverse needs including the protection of life, property, the environment, and our economy.

Centennial Streamgages are USGS streamgages that have been in operation for more than 100 years.

WaterNow is no longer available as of December 15, 2023. An alternative USGS service, called WaterAlert, is available. WaterAlert provides notifications to your email or phone for changes in water conditions based on thresholds you choose.

Users access USGS water data in various ways, including using automated scripts and functions. Computational tools are open-source software and code resources that make USGS water data easily discoverable, accessible and usable. These tools perform tasks such as retrieving data, calculating statistics, and creating visualizations.

MODFLOW is the USGS's modular hydrologic model. MODFLOW is considered an international standard for simulating and predicting groundwater conditions and groundwater/surface-water interactions. MODFLOW 6 is presently the core MODFLOW version distributed by the USGS.

This website compiles USGS resources and data related to principal aquifers including Aquifer Basics, principal aquifers maps and GIS data, and the National Aquifer Code Reference List.

SPARROW mappers are interactive tools that allow the user to explore river streamflow and nutrient and sediment loads and yields and the importance of different sources of contaminants in a particular river basin. Data can be visualized using maps and interactive graphs and tables, and rankings can be shown by state, major watershed, hydrologic unit (HUC), and catchment.

Water data visualizations are provocative visuals and captivating stories that inform, inspire, and empower people to address our Nation's most pressing water issues. USGS data science and visualization experts use visualizations to communicate water data in compelling and often interactive ways when static images or written narrative can’t effectively communicate the interconnectivity and...

Offering a wide-range of environemental analytical services, the U.S. Geological Survey (USGS) National Water Quality Laboratory (NWQL) is a world-class environmental analysis and research laboratory located on the campus of the Denver Federal Center in Lakewood, Colorado.