Publications

Elevated levels of dissolved solids in water (salinity) can result in numerous and costly issues for agricultural, industrial, and municipal water users. The Colorado River Basin Salinity Control Act of 1974 (Public Law 93-320) authorized planning and construction of salinity-control projects in the Colorado River Basin. One of the first projects was the Lower Gunnison Unit, a project to...

Concentrations of nitrogen, phosphorus, and suspended sediment are measured at the U.S. Geological Survey streamgage at Conowingo Dam at the downstream end of the Susquehanna River Basin in Maryland, where the river flows into the Chesapeake Bay. During the period September 7-15, 2011, in the aftermath of Tropical Storm Lee, concentrations of these three constituents were among the...

The Edwards aquifer in south-central Texas is a productive and important water resource. Several large springs issuing from the aquifer are major discharge points, popular locations for recreational activities, and habitat for threatened and endangered species. Discharges from Comal and San Marcos Springs, the first and second largest spring complexes in Texas, are used as thresholds in

The U.S. Geological Survey, in cooperation with the U.S. Department of Energy, analyzed water-quality data collected from 67 aquifer wells and 7 surface-water sites at the Idaho National Laboratory (INL) from 1949 through 2009. The data analyzed included major cations, anions, nutrients, trace elements, and total organic carbon. The analyses were performed to examine water-quality trends...

In May and June 2012, the Whitewater-Baldy Fire burned approximately 1,200 square kilometers (300,000 acres) of the Gila National Forest, in southwestern New Mexico. The burned landscape is now at risk of damage from postwildfire erosion, such as that caused by debris flows and flash floods. This report presents a preliminary hazard assessment of the debris-flow potential from 128 basins...

The 2010 Schultz fire northeast of Flagstaff, Arizona, burned more than 15,000 acres on the east side of San Francisco Mountain from June 20 to July 3. As a result, several drainages in the burn area are now more susceptible to increased frequency and volume of runoff, and downstream areas are more susceptible to flooding. Resultant flooding in areas downgradient of the burn has resulted...

The maps and graph in this summary describe streamflow conditions for water year 2011 (October 1, 2010, to September 30, 2011) in the context of the 82-year period from 1930 through 2011, unless otherwise noted. The illustrations are based on observed data from the U.S. Geological Survey's (USGS) National Streamflow Information Program (http://water.usgs.gov/nsip/). The period 1930-2010...

An increased demand for fresh groundwater resources in South Florida has prompted Miami-Dade County to expand its water reclamation program and actively pursue reuse plans for aquifer recharge, irrigation, and wetland rehydration. The U.S. Geological Survey, in cooperation with the Miami-Dade Water and Sewer Department (WASD) and the Miami-Dade Department of Environmental Resources...

The U.S. Geological Survey Upper Klamath Lake water-quality monitoring program collected data from multiparameter continuous water-quality monitors, weekly water-quality samples, and meteorological stations during 2009 and 2010 from May through November each year. The results of these measurements and sample analyses, as well as quality-control data for the water-quality samples, are...

The U.S. Geological Survey (USGS), in cooperation with the U.S. Department of Energy, evaluated a three-dimensional model of groundwater flow in the fractured basalts and interbedded sediments of the eastern Snake River Plain aquifer at and near the Idaho National Laboratory to determine if model-derived estimates of groundwater movement are consistent with (1) results from previous...

The surficial deposits, areal extent of aquifers, and the water-table configurations of the stratified-drift aquifer systems in the Cayuta Creek and Catatonk Creek valleys and their large tributary valleys in Tompkins, Schuyler, Chemung, and Tioga Counties, New York were mapped in 2009, in cooperation with the New York State Department of Environmental Conservation. Well and test-boring...

A flexible Surface-Water Routing (SWR1) Process that solves the continuity equation for one-dimensional and two-dimensional surface-water flow routing has been developed for the U.S. Geological Survey three-dimensional groundwater model, MODFLOW-2005. Simple level- and tilted-pool reservoir routing and a diffusive-wave approximation of the Saint-Venant equations have been implemented...