Suspended-solids concentration data were collected in Central and South San Francisco Bays during water years 1992 and 1993. Optical backscatterance sensors were used to monitor suspended solids at three sites in South San Francisco Bay and at two sites in Central San Francisco Bay. Sensors were positioned at two depths at each site, mid-depth and near-bottom. Water samples were collected periodically and were analyzed for concentrations of suspended solids. The results of the analyses were used to calibrate the electrical output of the optical backscatterance sensors. This report presents the data-collection methods used and summarizes the suspended-solids concentration data collected from December 1991 through September 1993. Calibration plots and edited data for each sensor also are presented. which limits photosynthesis and primary production (Cloem, 1987; Cole and Cloem, 1987), and deposit in ports and shipping channels, which require dredging (U.S. Environmental Protection Agency, 1992). The U.S. Geological Survey (USGS), in cooperation with the San Francisco Regional Water Quality Control Board (South Bay) and the U.S. Army Corps of Engineers (Central Bay), is studying the factors that affect suspended-solids concentrations in San Francisco Bay. Purpose and Scope This report summarizes suspended-solids concentration data collected by the USGS in Central and South San Francisco Bays in water years 1992 and 1993. Complete data are available from the files of the USGS in Sacramento. Suspended-solids concentrations were monitored at two sites in Central San Francisco Bay and at three sites in South San Francisco Bay.

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Optical backscatterance sensors and water samples were used to monitor suspended solids at two sites in Suisun Bay, three sites in Central San Francisco Bay, and three sites in South San Francisco Bay. Sensors were positioned at two depths at most sites. Water samples were collected periodically and were analyzed for concentrations of suspended solids. The results of the analyses were used to calibrate the electrical output of the optical backscatterance sensors. This report presents the data-collection methods used and summarizes the suspended-solids concentration data collected from October 1997 through September 1998. Calibration plots and plots of edited data for each sensor also are presented.

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Suspended-sediment concentration data were collected by the U.S. Geological Survey in San Francisco Bay during water year 2005 (October 1, 2004-September 30, 2005). Optical sensors and water samples were used to monitor suspended-sediment concentration at two sites in Suisun Bay, three sites in San Pablo Bay, two sites in Central San Francisco Bay, and three sites in South San Francisco Bay. Sensors were positioned at two depths at most sites. Water samples were collected periodically and analyzed for concentrations of suspended sediment. The results of the analyses were used to calibrate the output of the optical sensors so that a record of suspended-sediment concentrations could be derived. This report presents the data-collection methods used and summarizes, in graphs, the suspended-sediment concentration data collected from October 2004 through September 2005. Calibration curves and plots of the processed data for each sensor also are presented.