Land-Use Change

SPARROW (SPAtially Referenced Regression On Watershed attributes) models estimate the amount of a contaminant transported from inland watersheds to larger water bodies by linking monitoring data with information on watershed characteristics and contaminant sources. Interactive, online SPARROW mapping tools allow for easy access to explore relations between human activities, natural processes, and...

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.

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.

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.

About 40 percent of the land in the United States is used for agriculture, and agriculture supplies a major part of the our food, feed, and fiber needs. Agricultural chemicals move into and through every component of the hydrologic system, including air, soil, soil water, streams, wetlands, and groundwater.

Humans, just like aquatic organisms, need water. Flood control, urban infrastructure, irrigation of agriculture, and myriad other ways we manage water affect the natural flow of streams and rivers. How do the ways we manage land and water affect the natural patterns of streamflow that ecosystems depend on?

Regional groundwater availability studies enable information about groundwater to be integrated and consistent, so that this resource can be analyzed and understood on an aquifer–wide scale. These studies provide decision–makers with a better understanding of the status and trends in the Nation's groundwater availability.

The goals of the Regional Stream Quality Assessment (RSQA) are to characterize multiple water-quality factors that are stressors to aquatic life (contaminants, nutrients, sediment, and streamflow alteration) and to develop a better understanding of the relation of these stressors to ecological conditions in streams throughout the region.

The USGS is undertaking a 3-year study of water availability and use to investigate competing societal and ecological needs in Southeastern Atlantic Coastal Basins of the Carolinas. This study will compile existing information, add new scientific data and interpretation, and develop tools to help resource managers and stakeholders address current and future water-use challenges.

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

Research by the USGS National Water Quality Assessment (NAWQA) Project on water quality of rivers and streams covers a broad range of topics, from nonpoint pollution issues to vulnerability of aquatic ecosystems. Dive in and find out more about current water-quality conditions, how and where water quality is changing, and the latest information on pesticides, nutrients, and other contaminants.

Reconnecting people and water is an increasingly important goal in many urban areas. Parks, urban trails, boat ramps, and urban agriculture all are ways that an urban population can interact with nature and improve quality of life. USGS is participating in gathering the information that will make these projects possible.