Publications

The rate of global mean sea-level rise (SLR) during the 20th century is estimated to be 1.7 mm yr−1 ±0.3 yr−1 (Church and White, 2006). SLR during the 20th century was a result of thermal expansion of the oceans and the release of water from terrestrial storage reservoirs (Bindoff et al., 2007). The latter process is thought to be dominated by the melting of glaciers and polar ice caps...

Sierra Nevada snowpack is a critical water source for California’s growing population and agricultural industry. However, because mountain winters and springs are warming, on average, precipitation as snowfall relative to rain is decreasing, and snowmelt is earlier. The changes are stronger at mid-elevations than at higher elevations. The result is that the water supply provided by...

Ground-water quality in the approximately 2,100 square-mile Southern Sacramento Valley study unit (SSACV) was investigated from March to June 2005 as part of the Statewide Basin Assessment Project of Ground-Water Ambient Monitoring and Assessment (GAMA) Program. This study was designed to provide a spatially unbiased assessment of raw ground-water quality within SSACV, as well as a...

A qualitative comparison was made of the streamgaging programs of the U.S. Geological Survey (USGS) and three non-Federal agencies in terms of approximate costs and streamflow-information products produced. The three non-Federal agencies provided the USGS with detailed information on their streamgaging program and related costs, and the USGS explored, through publicly available Web sites...

The watershed of Fivemile Creek (FMC), a tributary to the Locust Fork of the Black Warrior River, is located north of Birmingham, Alabama. Areas that have been previously coal-mined border the creek, and portions of the upper watershed have been and are currently (2007) being used for industrial and urban uses. The U.S. Geological Survey (USGS), in cooperation with the City of Tarrant...

A modified siphon sampler (or 'single-stage sampler') was developed to sample shallow water at closely spaced vertical intervals. The modified design uses horizontal rather than vertical sample bottles. Previous siphon samplers are limited to water about 20 centimeters (cm) or more in depth; the modified design can sample water 10 cm deep. Several mounting options were used to deploy the...

Throughout the Southwest, state and federal water-resource managers are becoming increasingly concerned about the impacts of future groundwater development on the region’s limited water resources, environmentally sensitive ecosystems, and rural lifestyle. To address their concerns, scientists and engineers are deploying physically based mathematical models to assess and predict the...

Following a wildfire, such as the 2002 Missionary Ridge fire, a number of hydrologic hazards may develop that can have an important impact on water resources, businesses, homes, reservoirs, roads, and utilities in the wildland urban interface (areas where homes and commercial developments are interspersed with wildlands) in mountainous areas of the Western United States. This fact sheet...

Sedimentation has reduced water storage in Kajakai Reservoir. If current sedimentation rates continue, hypothetical future reservoir water volumes at the spillway elevation of 1,033.5 meters could be reduced about 22 percent from 2006 to 2057. Even if the spillway elevation is raised to 1,045 meters, a severe drought could result in large multiyear irrigation-supply deficits in which...

Thick, heterogeneous unsaturated zones away from large streams in desert areas have not previously been considered suitable for artificial recharge from ponds. To test the potential for recharge in these settings, 1.3 x 106 m3 of water was infiltrated through a 0.36-ha pond along Oro Grande Wash near Victorville, California, between October 2002 and January 2006. The pond overlies a...

Hydraulic tomography is a powerful technique for characterizing heterogeneous hydrogeologic parameters. An explicit trade-off between characterization based on measurement misfit and subjective characterization using prior information is presented. We apply a Bayesian geostatistical inverse approach that is well suited to accommodate a flexible model with the level of complexity driven...

Subsurface fate and transport of the antibiotic sulfamethoxazole (SX), the non-ionic surfactant degradation product 4-nonylphenol (NP), and the sex hormone 17β-estradiol (E2) were evaluated in a plume of contaminated groundwater at Cape Cod, Massachusetts, USA. The plume is the result of 60 years of wastewater treatment plant effluent disposal into rapid infiltration beds. Natural...