Measuring and Monitoring Water

The Nation's rivers and streams are a priceless resource, but pollution from urban and agricultural areas pose a threat to our water quality. To understand the value of water quality, and to more effectively manage and protect the Nation's water resources, it's critical that we know the current status of water-quality conditions, and how and why those conditions have been changing over time.

Water and the chemicals it contains are constantly being exchanged between the land surface and the subsurface. Surface water seeps into the ground and recharges the underlying aquifer—groundwater discharges to the surface and supplies the stream with baseflow. USGS Integrated Watershed Studies assess these exchanges and their effect on surface-water and groundwater quality and quantity.

Hydraulic fracturing, commonly known as fracking, is the process of injecting water, sand, and/or chemicals into a well to break up underground bedrock to free up oil or gas reserves. The USGS monitors the environmental impact of this practice across the country, from potential earthquakes to degraded groundwater quality.

More than 80 percent of known land subsidence in the U.S. is a consequence of groundwater use, and is an often overlooked environmental consequence of our land and water-use practices. Increasing land development threatens to exacerbate existing land-subsidence problems and initiate new ones. Subsidence detection and mapping done by the USGS is needed to understand and manage our current and...

The USGS Quality Systems Branch (QSB) represents the Water Resource Mission Area’s commitment to generating environmental data of known quality. QSB produces water and sediment performance-assessment samples and data to provide the USGS laboratory users, USGS laboratories, and field personnel with quantitative performance information to assess data quality.

USGS Cooperative Matching Funds (CMF) support joint projects with our state, regional, tribal, and local partners to provide reliable, impartial, and timely information needed to understand and manage the Nation's water resources.

Focus Area Studies were stakeholder-driven assessments of water availability in river basins with known or potential conflict. They contributed toward ongoing assessments of water availability in large watersheds, provided opportunities to test and improve approaches to water availability assessment, and informed the National Water Census with local information. These studies focused on key water...

The NASA-USGS National Blue Carbon Monitoring System project will evaluate the relative uncertainty of iterative modeling approaches to estimate coastal wetland (marsh and mangrove) C stocks and fluxes based on changes in wetland distributions, using nationally available datasets (Landsat) and as well as finer scale satellite and field derived data in six sentinel sites.

Intensive studies by the USGS National Water-Quality Assessment (NAWQA) Project in agricultural areas provide insight into how agricultural activities have altered the natural flow of water and the way that agricultural chemicals enter streams and aquifers, and in particular how nutrients affect algal and invertebrate communities in agricultural streams.

All natural waters contain some dissolved solids (salinity) from contact with soils, rocks, and other natural materials. Too much, though, and dissolved solids can impair water use. Unpleasant taste, high water-treatment costs, mineral accumulation in plumbing, staining, corrosion, and restricted use for irrigation are among the problems associated with elevated concentrations of dissolved solids.

Oil spills, such as the 2010 Deepwater Horizon Oil Spill, are impactful environmental disasters that have long lasting effects to the landscape, native species, and inhabitants who depend on the area. The USGS explores the adverse effect that large-scale oil spills have on the environment and helps responders prepare for environmental recovery and rehabilitation.

Public supply refers to water withdrawn by public and private water suppliers that provide water to at least 25 people or have a minimum of 15 connections. Public-supply water is delivered to users for domestic, commercial, and industrial purposes. Part of the total is used for public services, such as public pools, parks, firefighting, water and wastewater treatment, and municipal buildings, and...