The California Department of Water Resources (CA-DWR), North Central Region Office (NCRO), Bathymetry Data Collection Section, conducted a bathymetric survey of selected parts of the Sacramento Deep Water Ship Channel and Lake Washington for the Bay Delta Office (BDO). The main purpose of the data is to obtain elevation data in the shoals to supplement a December 2018 interferometric survey by USGS, to validate other datasets, and to replace outdated and inaccurate data in some areas. A separate multibeam survey was conducted for the Ship Channel headwaters, from the Industrial Blvd. overpass east to the Sacramento River locks. These data will inform modeling efforts to aid in the evaluation of a large number of restoration proposals nearby. The data were collected in NAD83 (California State Plane Zone II coordinate system) and NAVD88 datums.• Survey Dates: August 5-8, 2019 • Instrumentation: Singlebeam echo sounder with Inertially-Aided Post-Processed Kinematic (IAPPK) GPS procedures. • Point Spacing: about 1 Foot• Horizontal Units: US Foot• Vertical Units: US Foot• Related datasets: Sacramento Deep Water Ship Channel Multibeam, August 2019; USGS Sacramento Deep Water Ship Channel Multibeam, December 2018 (EXTERNAL);

The California Department of Water Resources (CA-DWR), North Central Region Office (NCRO), Bathymetry Data Collection Section, conducted a targeted singlebeam bathymetric survey on the Sacramento River near Clarksburg for the Delta Conveyance Office. This singlebeam data is not intended to provide enough points to interpolate a surface, the main purpose of the data is to serve as an independent check on multibeam data collected on the same date. The survey was conducted in tandem with the multibeam survey with the singlebeam vessel trailing just beyond the turbulent influence of the lead vessel, about 100 yards. The echosounder was operated 200 kHz, and may penetrate slightly further into the bed substrate than the 455 kHz multibeam sonar. The data were collected in NAD83 (California State Plane Zone III coordinate system) and NAVD88 datums.• Survey Date: April 17, 2019 • Instrumentation: Singlebeam echo sounder with Inertially-Aided Post-Processed Kinematic (IAPPK) GPS procedures. • Point Spacing: about 1 Foot• Horizontal Units: US Foot• Vertical Units: US Foot• Related datasets: Sacramento River at Clarksburg (multibeam), April 2019