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High-resolution (1 m) digital elevation model (DEM) of San Francisco Bay, California, created using bathymetry data collected between 1999 and 2020 (ver. 2.0, July 2021)

July 8, 2021

A 1-m resolution bathymetric digital elevation model (DEM) of all off San Francisco Bay was constructed from bathymetric surveys collected from 1999 to 2016. The DEM has been divided into northern and southern sections due to file size, and is available in both MLLW and NAVD88 versions.

Background: In 2014 and 2015 the California Ocean Protection Council (OPC) contracted the collection of bathymetric surveys of large portions of San Francisco Bay. A total of 93 surveys were collected using a combination of multibeam and interferometric side scan sonar systems. Of those 93 surveys, 75 consist of swaths of data ranging from 18- to just over 100-meters wide. These swaths were separated by data gaps ranging from 10- to just over 300-meters wide. The no-data areas required interpolation to create a continuous surface. The creation of this DEM refines techniques developed by the USGS to create DEMS from historic bathymetric data. The OPC surveys, along with those collected by the United States Geological Survey (USGS), National Oceanic and Atmospheric Administration (NOAA), NOAA's National Ocean Service (NOS), and the United States Army Corps of Engineers (USACE), allow the creation of a continuous, high-resolution bathymetric surface that can be compared to earlier surveys to delineate regions of sediment erosion and deposition.