Measuring and Monitoring Water

Our surface water, groundwater, and aquatic ecosystems are priceless resources, used by people across the Nation for drinking, irrigation, industry, and recreation. The National Water-Quality Assessment (NAWQA) Project is a leading source of scientific data and knowledge for development of science-based policies and management strategies to improve and protect our water resources.

The USGS maintains sediment laboratories in several Water Science Centers and offices across the country.

USGS develops and uses “surrogate” techniques to estimate sediment at times when it can’t be physically measured through samples.

USGS collects sediment samples at thousands of locations across the U.S. using nationally consistent methods.

A streamgage is a structure installed beside a stream or river that contains equipment that measures and records the water level (called gage height or stage) of the stream. Streamflow (also called discharge) is computed from measured water levels using a site-specific relation (called a stage-discharge rating curve) developed from onsite water level and streamflow measurements made by USGS...

Federal Priority Streamgages (FPS) are monitoring stations that track the amount of water in streams and rivers across the Nation and that meet one or more strategic, long-term Federal information needs. FPS are strategically positioned across the Nation to serve, in part, as a “backbone” of 4,756 eligible sites for the larger USGS streamgaging network of 11,885 sites (2023) that is operated by...

Since the early 1980s the USGS has worked cooperatively with manufacturers to develop and enhance the use of acoustic Doppler instruments for streamflow and other hydraulic measurements. This site provides information on hydroacoustic technology, instruments, and their use.

Like people, plants need nutrients, but too much of a good thing can be a problem. Nutrients, such as nitrogen and phosphorus, occur naturally, but most of the nutrients in our waterways come from human activities and sources—fertilizers, wastewater, automobile exhaust, animal waste. The USGS investigates the source, transport, and fate of nutrients and their impacts on the world around us.

Wherever you live, there’s a creek or stream near you. The eighty percent of Americans who live in metropolitan areas are often unaware of the network of urban creeks—many teeming with life—that weaves through our cities and town. Nowhere are the environmental changes associated with urban development more evident than in urban streams.

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.

Data scientists in the USGS Water Resources Mission Area make sense of large environmental and operational datasets by applying various modeling, statistical, and visualization techniques to generate actionable information.

The enhanced probability of catastrophic wildfires has increased our need to understand the risk of floods, erosion, and debris and contaminant transport in burned watersheds. This project investigates the relation between rainfall intensity and peak discharge; erosion and deposition processes; and water-quality impacts to minimize the loss of life and property resulting from post-wildfire floods.