Suspended-sediment dynamics in the tidal reach of a San Francisco Bay tributary

Gregory Shellenbarger; Maureen A. Downing-Kunz; David H. Schoellhamer

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USGS · 70176591

Suspended-sediment dynamics in the tidal reach of a San Francisco Bay tributary

Gregory Shellenbarger·Maureen A. Downing-Kunz·David H. Schoellhamer

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Abstract

To better understand suspended-sediment transport in a tidal slough adjacent to a large wetland restoration project, we deployed continuously-measuring temperature, salinity, depth, turbidity, and velocity sensors since 2010, and added a dissolved-oxygen sensor in 2012, at a near-bottom location in Alviso Slough (Alviso, California USA). Alviso Slough is the downstream reach of the Guadalupe River and flows into the far southern end of San Francisco Bay. River flow is influenced by the Mediterranean climate, with high flows correlated to episodic winter storms (~85 m3 s-1) and low base flow during the summer (~0.85 m3 s-1). Storms and associated runoff have the greatest influence on sediment flux. Strong spring tides promote upstream sediment flux and weak neap tides have only a small net flux. During neap tides, stratification likely suppresses sediment transport during weaker flood and ebb tides.

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Source-reported bounding extent: 35.94688293218141° to 37.47485808497102° latitude; -122.05810546875° to -120.574951171875° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Gregory Shellenbarger, Maureen A. Downing-Kunz, David H. Schoellhamer. 2015. Suspended-sediment dynamics in the tidal reach of a San Francisco Bay tributary. https://pubs.usgs.gov/publication/70176591

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