Images

View of the Green River along a trail in Mammoth Cave National Park.  USGS operates gages on the river above and below the Park Boundaries. 

View of the Green River along a trail in Mammoth Cave National Park.  USGS operates gages on the river above and below the Park Boundaries. 

Coconut palm, sea grapes, and a white sand beach overlooking Drake's Passage from the island of Tortola in the British Virgin Islands.

Resource professionals stand in the rain beside a mountain stream.

USGS hydrologist conducts a ground-penetrating radar survey to investigate and characterize the shallow subsurface. The survey was conducted as part of an applied research effort by the USGS Office of Groundwater Branch of Geophysics in 2006.

USGS hydrologist conducts a two-dimensional (2D) resistivity survey to investigate and characterize the shallow subsurface. The survey was conducted as part of an applied research effort by the USGS Office of Groundwater Branch of Geophysics in 2006.

Streamwater flowing over a rural road in Highland County, Virginia, June, 2006.

Sediment cores from lakes and reservoirs can be used to reconstruct contaminant histories in watersheds. Sediment-core analyses indicate that concentrations of PAHs in many U.S. urban lakes are increasing, and multiple lines of evidence indicate that the source of the PAHs in coal-tar-based pavement sealants.

Dust was collected from sealcoated pavements across the U.S. Concentrations of polycyclic aromatic hydrocarbons (PAHs) in dust from sealed pavement in the East, where coal-tar-based products are used, was about 1,000 times higher than in dust from sealed pavement in the  West, where asphalt-based products are used.

Mark Sandheinrich and Sean Bailey of the University of Wisconsin - La Crosse sampling fish from a canoe on Shoepack Lake in Voyageurs National Park. A burned tree is in the foreground from a previous wildland fire.

Mark Sandheinrich and Sean Bailey of the University of Wisconsin - La Crosse sampling fish from a canoe on Shoepack Lake in Voyageurs National Park.

USGS hydrologist conducts a broadband electromagnetic survey in New Orleans, Louisiana. The survey was one of several geophysical methods used during USGS applied research on the utility of the multi-channel analysis of surface waves (MASW) seismic method for non-invasive assessment of earthen levees.

USGS hydrologists conduct a seismic survey in New Orleans, Louisiana. The survey was one of several geophysical methods used during USGS applied research on the utility of the multi-channel analysis of surface waves (MASW) seismic method (no pictured here) for non-invasive assessment of earthen levees.

USGS personnel measuring flood overflow near Whitey's Restaurant in East Grand Forks.

Wyoming-Montana Water Science Center comparison discharge measurement

The Flint River below Bainbridge, Georgia, showing base flow conditions. Even at low flows, rivers in this part of Georgia contain enough sediment to color the water brown.

Red River of the North flooding the 1st Avenue North Bridge in Fargo, ND.

The Wild Rice River near Abercrombie, North Dakota flooding.

Domestic well on the Arapahoe Aquifer from the USGS Circular 1357 "Water Quality in the Denver Basin Aquifer System, Colorado, 2003-2005."

Scenic view of paragliding by coastline at Torrey Pines State Reserve.

Scenic view of paragliding by coastline at Torrey Pines State Reserve.