Measuring and Monitoring
Measuring and Monitoring
Basic hydrologic data collection, processing, analysis, dissemination, and archiving are major parts of the California Water Science Center program. Streamflow data, for example, are used for flood and water-supply forecasts, planning and design, river regulation, streamflow statistics, and research investigations. Much of the data are available on a near-real-time basis by satellite telemetry.
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Land Subsidence in the Coachella Valley
Groundwater is an important water-supply source in the Coachella Valley. The demand for water has exceeded the deliveries of imported surface water, and groundwater levels have been declining as a result of increased pumping. A network of GPS stations has been set up in the valley to monitor subsidence resulting from declining groundwater levels.
San Antonio Reservoir Bathymetric Survey and Sedimentation Study
Over time, the flow of water into the San Antonio Reservoir has caused the build-up of sediment, decreasing storage capacity. Since water storage is a crucial issue in California, up-to-date information on the reservoir is needed. To accomplish this, the San Francisco Public Utilities Commission approached the USGS California Water Science Center to conduct a bathymetric (depth) survey and other...
Delta-Mendota Canal: Using Groundwater Modeling to Analyze Land Subsidence
A numerical modeling approach was used to quantify groundwater conditions and land subsidence spatially along the Delta-Mendota Canal. In addition, selected management alternatives for controlling land subsidence were evaluated.
Development of Precipitation-Runoff Modeling System (PRMS) for the Kings River Basin, California, with application for streamflow predictability and flood forecasting
This study will provide an analysis tool for forecasting seasonal and longer term streamflow variations, and for evaluating climate and land cover variations in the Kings River Basin. This study will directly or indirectly address several water-resource issues identified in the USGS Science Strategy document (USGS, 2007): drinking water availability, the suitability of aquatic habitat for biota...
Nitrogen Dynamics Along the Sacramento River and Links to Phytoplankton Dynamics: Resolving Spatial and Temporal Variability Using In-Situ, High-Frequency Measurements and Other Tools
The overall project objective is to further our understanding of the link between nitrogen and phytoplankton dynamics in the Sacramento River and to elucidate effects of wastewater treatment plant effluent on food web dynamics.
Bay Area Ensemble Modeling for Conservation and Biodiversity
The objective of this study is to provide downscaled ensemble projections of climate and hydrology for the next century for the state of California with specific application to the San Francisco Bay Area.
Development of unimpaired flows for mountain basins draining to the Bay Delta
The objective of this study is to develop daily historical climate surfaces and simulate unimpaired basin discharge, including surface water flow and baseflow, from all basins that drain to the Bay Delta. Basin drainage will be calibrated to DWR reconstructed flows, and comparisons of results will be made with other independently developed watershed models for basins in which they coincide. A...
Delta-Mendota Canal: Evaluation of Groundwater Conditions and Land Subsidence
In areas adjacent to the Delta-Mendota Canal (DMC), extensive groundwater withdrawal from the San Joaquin Valley aquifer system has caused areas of the ground to sink as much as 10 feet, a process known as land subsidence. This could result in serious operational and structural issues for the Delta-Mendota Canal (DMC). In response, the USGS is studying and providing information on groundwater...
Interactions Between Physical Processes and Suspended Sediment Quality in Relation to Spawning Migrations of Delta Smelt
The proposed study is designed to better establish relationships between patterns of delta smelt abundance and properties of suspended particles as measured by optical and acoustical techniques.
Causes and Relevance of Phytoplankton Blooms in the Northern Sacramento-San Joaquin Delta
Phytoplankton are an important part of aquatic food webs and ecosystems. These single-celled plants grow faster in the stronger light of spring or summer, resulting in population explosions called phytoplankton blooms. These blooms in turn feed zooplankton (free-floating aquatic microorganisms), providing food for many aquatic species, including fish, shrimp, crabs, and other invertebrates.
Improved Lower South Bay suspended-sediment flux measurements
Tidal marshes provide animal habitats and prevent erosion. Expanding towns and cities have claimed major parts of San Francisco Bay’s marshland. Sediment deposits are essential to rebuilding tidal marshes and keeping existing marshes intact. In the southern part of the Bay, the largest tidal wetland restoration project on the west coast is underway. Sediment flux measurements are key in deciding...
Water-level Contour Map of the Antelope Valley Groundwater Basin and Interactive Website, 2014
The USGS has a long history of collecting water-level data in the Antelope Valley groundwater basin. Previous water-level contour maps for Antelope Valley were published by the USGS in cooperation with the Antelope Valley – East Kern Water Agency as Open-File Reports 80-1222, 86-498 and 98-4022 using water-level data collected in 1979, 1984 and 1996, respectively. An updated water-level contour...