California Water Science Center

The USGS and State Water Board Oil and Gas Regional Groundwater Monitoring Program are hosting a webinar Friday, February 19 at 10am PT to discuss the scientific findings of the Groundwater Quality of Aquifers Overlying the Oxnard Oil Field, Ventura County, California study.

California Water Science Center scientists have begun the first comprehensive assessment of sediment nutrient inventories and fluxes in the Sacramento-San Joaquin Delta (Delta). Their findings will serve as a baseline for assessing water quality improvements following upcoming upgrades to the Sacramento Regional Wastewater Treatment Plant and wetland restoration efforts.

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Many non-native fish, invertebrates, and plants have colonized the Delta over the past century. Included among these species is the water primrose (Ludwigia grandiflora ssp. hexapetala and Ludwigia peploides), an aggressive floating aquatic plant native to South and Central America and parts of the US, but invasive in California.

In the past decade, Salton Sea water elevation has declined due to drought, lining of canals, and changes to management of the Colorado River. This has resulted in the creation of new wetlands caused by drains and rivers no longer reaching the Salton Sea.

The U.S. Geological Survey announced Friday the completion of a new mobile tool that provides real-time information on water levels, weather and flood forecasts all in one place on a computer, smartphone or other mobile device. 

In an article for the journal Science of the Total Environment, USGS scientists and others discuss the impact of invasive quagga mussels on the ecosystem of Lake Mead located on the border of Arizona and Nevada. 

The health of the San Francisco Bay‐Delta depends on a sediment supply that has been recently declining due to sediment trapping in upstream reservoirs. Reduced sediment supply increases water clarity in the Bay-Delta, which in turn influences ecological processes and aquatic life.

The Sacramento Regional County Sanitation District (Regional San) is currently completing major upgrades to its wastewater treatment plant. In anticipation of these upgrades, USGS scientists are gathering data to establish baselines for current nutrient levels and dynamics in the Sacramento-San Joaquin Delta (Delta). 

The USGS Nevada and California Water Science Centers participate in annual Lake Tahoe Summit

Over the last few decades the Sacramento-San Joaquin River Delta has experienced declines in phytoplankton productivity and a shift in species composition resulting in observed increases in harmful algal blooms (HABs).