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Web Tools

The USGS offers many helpful online tools to answer your water-related questions. Check out what we offer below!

Filter Total Items: 19

WaterQualityWatch

WaterQualityWatch provides access to real-time water-quality data collected at more than 2,000 stream sites throughout the United States, including streamflow, water temperature, specific conductance, pH, dissolved oxygen, turbidity, and nitrate.

WaterWatch (surface water)

WaterWatch displays maps, graphs, and tables describing real-time, recent, and past streamflow conditions for the United States, including flood and droughts. Real-time information generally is updated on an hourly basis.

Hydrologic Unit Maps

The U.S. is sub-divided into successively smaller hydrologic units which are classified into four levels: regions, sub-regions, accounting units, and cataloging units. Each unit is identified by a unique hydrologic unit code (HUC) consisting of two to eight digits based on its classification. This site provides information and data for current and historical hydrologic units, names, and numbers.

USGS Flood Event Viewer

During large, short-term events, the USGS collects streamflow and additional data (including storm tide, wave height, high-water marks, and additional sensor deployments) to aid in documenting flood events. The USGS Flood Event Viewer provides convenient, map-based access to downloadable event-based data.

Federal Priority Streamgages (FPS) Mapper

This mapper identifies USGS Federal Priority Streamgages (FPS). FPS are monitoring stations that track the amount of water in streams and rivers across the Nation to meet long-term federal information needs. They are strategically positioned to serve as a backbone for the larger National Streamflow Network that is operated in cooperation with over 1,200 federal, state, tribal, and local agencies.

Principal Aquifers of the United States

A principal aquifer is defined as a regionally extensive aquifer or aquifer system that has the potential to be used as a source of potable water. This site provides downloadable maps (Ground Water Atlas of the United States, 2003) and spatial data (National Atlas, 2014) for the principal aquifers and aquifers of alluvial and glacial origin of the U.S.

National Ground-Water Monitoring Network (NGWMN) Data Portal

The NGWMN Data Portal provides access to groundwater data from multiple, dispersed databases in a web-based mapping application. The Portal contains current and historical data including water levels, water quality, lithology, and well construction.

Maps and GIS Data

Explore water resources maps and GIS data.

Flood Inundation Mapper

USGS Flood Inundation Maps, along with Internet information regarding current stage from the USGS streamgage, provide emergency management personnel and residents with information that is critical for flood-response activities, such as evacuations and road closures, as well as for post-flood recovery efforts.

Endangered, Discontinued, and Rescued Streamgages Mapper

This mapper identifies USGS streamgages that are in danger of being discontinued or converted to a reduced level of service due to lack of funding, gages that already have been discontinued, and gages that have been ‘rescued’ by a new funding source.

Science in Your Watershed

The Science in Your Watershed website helps you find scientific information organized on a watershed basis. This information, coupled with observations and measurements made by the watershed groups, provides a powerful foundation for characterizing, assessing, analyzing, and maintaining the status and health of a watershed.