Streams and Rivers

Karst terrain is created from the dissolution of soluble rocks, principally limestone and dolomite. Karst areas are characterized by distinctive landforms (like springs, caves, sinkholes) and a unique hydrogeology that results in aquifers that are highly productive but extremely vulnerable to contamination.

The U.S. Geological Survey is integrating its water science programs to better address the Nation’s greatest water resource challenges. At the heart of this effort are plans to intensively study several Integrated Water Science (IWS) basins—medium-sized watersheds (10,000-20,000 square miles) and underlying aquifers—over the next decade. The IWS basins will represent a wide range of environmental...

The Next Generation Water Observing System (NGWOS) supports water availability assessments, management, and prediction by enhancing water observations in basins that represent major U.S. hydrologic regions. NGWOS provides high-resolution, real-time data on water quantity, quality, and use, as well as advance the development and application of new sensor technologies and remote sensing methods.

The Next Generation Water Observing System provides high-fidelity, real-time data on water quantity, quality, and use to support modern water prediction and decision-support systems that are necessary for informing water operations on a daily basis and decision-making during water emergencies. The Illinois River Basin provides an opportunity to implement the NGWOS in a system challenged by an...

The Next Generation Water Observing System (NGWOS) provides high-fidelity, real-time data on water quantity, quality, and use to support modern prediction and decision-support systems that are necessary for informing water operations on a daily basis and decision-making during water emergencies. The headwaters of the Colorado and Gunnison River Basins provide an opportunity to implement NGWOS in a...

The Next Generation Water Observing System (NGWOS) supports water availability assessments, management, and prediction by enhancing water observations in basins that represent major U.S. hydrologic regions. The Delaware River Basin was the first Integrated Water Science basin selected, providing an opportunity to implement the NGWOS program in a nationally important, complex interstate river...

Flood-frequency analysis provides information about the magnitude and frequency of floods based on records of annual maximum instantaneous peak discharges. Accurate flood-frequency estimates, created using consistent and uniformly applied methods, are a key component of any effective flood risk and management program. This is a list of current USGS flood frequency reports published by state.

Powder River rises in the Bighorn Mountains of Wyoming and flows northward through a semi-arid landscape in Wyoming and Montana to the Yellowstone River. The river drains an area of 34,700 square kilometers and has an average discharge of about 500 million cubic meters per year. Cross-channel profile data were collected at 22 sites on the river and its tributaries from 1975 through 2014.

The USGS serves as the lead agency for the United States to measure and apportion natural flows of the St. Mary and Milk Rivers according to the Boundary Waters Treaty of 1909 and the International Joint Commission Order of 1921. The division of water between the United States and Canada is overseen by the Accredited Officers of the St. Mary and Milk Rivers, who are appointed by their respective...

In 2019, the USGS began studying the baseline water-quality of selected transboundary rivers in the Pacific Northwest. These studies are designed to characterize current water-quality conditions so as to facilitate future assessments of potential impacts related to upstream mining activities.

Declining snow cover is playing a key role in decreasing the flow of the Colorado River, “the lifeblood of the Southwest,” by enabling increased evaporation. As the warming continues, increasingly severe water shortages are expected.

USGS water-related projects of international interest.