Reports

No abstract available.

Nutrients such as nitrogen and phosphorus are important for aquatic ecosystem health. Excessive amounts of nutrients, however, can make aquatic ecosystems harmful for biota because enhanced growth and decay cycles of aquatic algae can reduce dissolved oxygen in the water. In Puget Sound marine waters, low dissolved oxygen concentrations are observed in a number of marine nearshore areas...

Significant Findings An analysis of total-dissolved-gas (TDG) and water-temperature data collected at eight fixed monitoring stations on the lower Columbia River in Oregon and Washington in water year 2014 indicated the following: All 81 TDG sensor laboratory checks that were performed after field deployment were within plus or minus (±) 0.5-percent saturation of a primary standard...

Park management of the Whiskeytown National Recreation Area, in northwestern California, identified a critical need to determine if mercury (Hg) or other elements originating from abandoned mines within the Upper Clear Creek watershed were present at concentrations that might adversely affect aquatic biota living within the park. During 2002–03, the U.S. Geological Survey, in cooperation...

The water gun is a tool adapted from deep marine geophysical surveys that is being evaluated for use as an acoustic fish deterrent to control the movement of invasive marine species. The water gun creates a seismic signal by using a compressed air discharge to move a piston rapidly within the water, resulting in an implosion. This energy pulse may be able to modify fish behavior or...

In winter 2011–12 and summer 2012, the U.S. Geological Survey (USGS), in cooperation with the U.S. Army Corps of Engineers, Albuquerque District and the U.S. Fish and Wildlife Service New Mexico Fish and Wildlife Conservation Office in Albuquerque, New Mexico, evaluated the physical characteristics and fish assemblage composition of available mesohabitats over a range of streamflows at...

The Coastal Plain of the southeastern United States has extensive, unconsolidated sedimentary deposits that are enriched in heavy minerals containing titanium, zirconium, and rare earth element resources. Areas favorable for exploration and development of these resources are being identified by geochemical data, which are supplemented with geological, geophysical, hydrological, and...

The U.S. Geological Survey, in cooperation with the Puerto Rico Electric Power Authority, completed a hydrologic and hydraulic study to assess the potential hazard to human life and property associated with the hypothetical failure of the Lago de Matrullas Dam, located within the headwaters of the Río Grande de Manatí. The hydrologic study yielded outflow hydrographs and peak discharges...

During the spring of 2012, the U.S. Geological Survey, in cooperation with the Arkansas Natural Resources Commission and the Arkansas Geological Survey, measured water levels in 342 wells completed in the Mississippi River Valley alluvial aquifer in eastern Arkansas. The Arkansas Natural Resources Commission measured water levels in 11 wells, and the U.S. Department of Agriculture...

The Arkansas Natural Resources Commission (ANRC) conducts an annual inventory of reported groundwater and surface-water withdrawals in Arkansas in cooperation with the U.S. Geological Survey (USGS). This report describes withdrawals from groundwater and surface-water resources in Arkansas for 2010. The report compiles withdrawals by county for 10 categories of water use—public supply...

The Julian 7.5' quadrangle lies within the Jurassic-Cretaceous Peninsular Ranges batholith of southern California and Baja California. Four granitic plutonic units and one gabbroic unit, most comprising a number of individual plutons, have been mapped in the Julian quadrangle and informal names have been assigned. The formal name Cuyamaca Gabbro has been retained. In addition to these...

The Hi-Desert Water District, in the community of Yucca Valley, California, is considering constructing a wastewater-treatment facility and using the reclaimed water to recharge the aquifer system through surface spreading. The Hi-Desert Water District is concerned with possible effects of this recharge on water quality in the underlying groundwater system; therefore, an unsaturated-zone