Streams and Rivers

As one of several Focus Area Studies within the USGS National Water Census (NWC), the USGS has completed a 3-year study of water availability and use in the Colorado River Basin.

Is water quality getting better or worse? Answering this deceptively simple question has been a fundamental objective of the USGS National Water-Quality Assessment Project’s research. Learn about trends in contaminants in the nation’s streams and rivers, trends in contaminants that collect in the bed sediment of streams and lakes, and changes in the quality of the nation’s groundwater.

Stream, river, and lake bed sediment are reservoirs for many contaminants. These contaminants include some “legacy” contaminants, like DDT, PCBs, and chlordane, and chemicals currently in use, like the insecticide bifenthrin and many flame retardants. Learn about techniques used to study sediment-associated contaminants and their importance to aquatic biota.

Who lives in your stream? Rivers and streams, even small ones, are teeming with a vast number of species, including fish, aquatic invertebrates, and algae. Stream ecology is the study of those aquatic species, the way they interrelate, and their interactions with all aspects of these flowing water systems.

When planning for a flood, there are three key questions that must be answered: What areas will be flooded? How deep will the flood waters get? When will the flood arrive? Historical flooding can help a community anticipate how much impact similar flood events could have, but there are other methods and tools that can provide more accurate and nuanced estimations of a wide variety of flood...

Floods are the leading cause of natural-disaster losses in the U.S. More than 75 percent of declared Federal disasters are related to floods, and annual flood losses average almost $8 billion with over 90 fatalities per year. Although the amount of fatalities has declined due to improved early warning systems, economic losses continue to rise with increased urbanization in flood-hazard areas.

On August 5, 2015, U.S. EPA was conducting an investigation of the Gold King Mine near Silverton, Colorado. While excavating as part of the investigation, water began leaking from the mine tunnel, and about three million gallons of water and sediment were released into Cement Creek, a tributary of the Animas River. The USGS provided pre- and post-release water-quality and streamflow data from...