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Digital Elevation Model of Little Holland Tract, Sacramento-San Joaquin Delta, California, 2015

January 6, 2016

This USGS Data Release presents data collected from bathymetric and topographic surveys and the resulting digital elevation model for the Little Holland Tract in the Sacramento-San Joaquin River Delta, California. During May and June of 2015, a team of scientists from the USGS Pacific Coastal and Marine Science Center (PCMSC) conducted multiple surveys (USGS Field Activity 2015-642-FA) to collect topographic and bathymetric data in the Little Holland Tract, located in the Sacramento-San Joaquin River Delta between Liberty Island and the Sacramento Deep Water Ship Channel. Topographic data were collected by survey personnel on foot and bathymetric measurements were collected using two personal watercraft (PWC). Positioning of both survey platforms was established using survey-grade Global Navigation Satellite Systems (GNSS). The GPS Backpack platform consisted of survey grade Trimble R10 and R7 GNSS receivers with Zephyr 2 antennas. The PWC platform consisted of Trimble R7 GNSS receivers with Zephyr 2 antennas combined with Odom Echotrac CV-100 single-beam echosounders and 200 kHz transducers. Additional topographic and bathymetric data were used to generate the final digital elevation model, including aerial Light Detection and Ranging (lidar) collected for the Department of Water Resources in 2007 and single beam bathymetric data collected by Environmental Data Solutions in 2009. Orthometric elevations relative to NAVD88 were computed using the National Geodetic Survey Geoid12a and the final data were projected in Cartesian coordinates using the UTM Zone 10 North (meters) coordinate system. The Digital Elevation Model (DEM) was created by interpolating between measurements as much as 100 meters apart, for this reason we cannot evaluate the accuracy of each point in the DEM, only the measurements it is based on. The mean estimated vertical uncertainties of the 2007 Department in the Water Resources lidar, the 2015 USGS GPS Backpack, and the 2015 USGS PWC survey data are 18.5, 3.5 and 6.1 cm, respectively.

Publication Year 2016
Title Digital Elevation Model of Little Holland Tract, Sacramento-San Joaquin Delta, California, 2015
DOI 10.5066/F7RX9954
Authors Alexander G Snyder, Andrew Stevens, Emily M Carlson, J. Lacy
Product Type Data Release
Record Source USGS Digital Object Identifier Catalog
USGS Organization Pacific Coastal and Marine Science Center