{ "culture": "en-US", "name": "", "guid": "", "catalogPath": "", "snippet": "The points represent the locations of soundings taken in 1934 by the US Coast and Geodetic Survey (USCGS). The points were digitized off of the georeferenced 1934 USCGS Hydrographic Survey No. 6008 maps by Justin Logan, DWR FESSRO on March of 2015 and referenced to NAD 1927 UTM Zone 10N. The sounding depths shown in the 1934 maps are in feet and referenced to the Mean Lower Low Water (MLLW) datum. The bottom elevations were calculated by subtracting the sounding depths from the DWR modeled tidal datum grid for MLLW. The VERTCON vertical datum conversion grid was used to convert from NAVD 88 elevations to NGVD 29. The elevation conversions were done by Karen Tolentino, DWR FESSRO on March 2015. The process used to convert the original soundings to orthometric heights is known to be subject to error, as the original MLLW value at Rio Vista was not known, and as MLLW itself is not \u201cflat\u201d, but instead slopes upward as one travels up-estuary, additional uncertainties exist. This dataset therefore may have considerable errors. The primary value of the dataset is due to it\u2019s significant historical nature. \n\nThe associated data are considered DWR enterprise GIS data, which meet all appropriate requirements of the DWR Spatial Data Standards, specifically the DWR Spatial Data Standard version 3.4, dated September 14, 2022. DWR makes no warranties or guarantees \u2014 either expressed or implied \u2014 as to the completeness, accuracy, or correctness of the data. DWR neither accepts nor assumes liability arising from or for any incorrect, incomplete, or misleading subject data. Comments, problems, improvements, updates, or suggestions should be forwarded to gis@water.ca.gov.", "description": "

Bathymetric survey of the Sacramento - San Joaquin Delta, stretching north-south from Lambert to Perrys Island and west-east from Perrys Island to Thornton. The survey took place in 1934 by the US Coast and Geodetic Survey (USCGS). Original field survey datums NAD 1927 (horizontal) and NGVD 29 (vertical) <\/SPAN>have been converted to California Teale Albers, NAD83 at time of field survey data import.<\/SPAN><\/P>

\u2022 Horizontal Units: Feet<\/SPAN><\/P>

\u2022 Vertical Units: Feet<\/SPAN><\/P>

<\/P><\/DIV><\/DIV><\/DIV>", "summary": "The points represent the locations of soundings taken in 1934 by the US Coast and Geodetic Survey (USCGS). The points were digitized off of the georeferenced 1934 USCGS Hydrographic Survey No. 6008 maps by Justin Logan, DWR FESSRO on March of 2015 and referenced to NAD 1927 UTM Zone 10N. The sounding depths shown in the 1934 maps are in feet and referenced to the Mean Lower Low Water (MLLW) datum. The bottom elevations were calculated by subtracting the sounding depths from the DWR modeled tidal datum grid for MLLW. The VERTCON vertical datum conversion grid was used to convert from NAVD 88 elevations to NGVD 29. The elevation conversions were done by Karen Tolentino, DWR FESSRO on March 2015. The process used to convert the original soundings to orthometric heights is known to be subject to error, as the original MLLW value at Rio Vista was not known, and as MLLW itself is not \u201cflat\u201d, but instead slopes upward as one travels up-estuary, additional uncertainties exist. This dataset therefore may have considerable errors. The primary value of the dataset is due to it\u2019s significant historical nature. \n\nThe associated data are considered DWR enterprise GIS data, which meet all appropriate requirements of the DWR Spatial Data Standards, specifically the DWR Spatial Data Standard version 3.4, dated September 14, 2022. DWR makes no warranties or guarantees \u2014 either expressed or implied \u2014 as to the completeness, accuracy, or correctness of the data. DWR neither accepts nor assumes liability arising from or for any incorrect, incomplete, or misleading subject data. Comments, problems, improvements, updates, or suggestions should be forwarded to gis@water.ca.gov.", "title": "i06_Bathy_USCGS_1934_Sacramento_and_MokelumneRiverSystems", "tags": [ "Elevation", "ISO 006", "Bathymetry", "Sacramento", "San Joaquin Delta", "1934", "bottom elevations", "Mokelumne River", "Georgiana Slough", "Snodgrass Slough", "Beaver Slough", "Dead Horse Cut", "Lost Slough", "DWR GIS Atlas" ], "type": "", "typeKeywords": [], "thumbnail": "", "url": "", "minScale": 150000000, "maxScale": 5000, "spatialReference": "", "accessInformation": "US Coast and Geodetic Survey (USCGS)", "licenseInfo": "

Not for use as a navigation aid. The data reflects measurements taken at specific time periods and the Department of Water Resources makes no claim as to the current state of these waterways. Do not share or publish this data without including proper attribution.<\/SPAN><\/P>

The original source projection of the DWR GIS atlas dataset was California Teale Albers, NAD83. For copies of data in original projection, please contact DWR directly.<\/SPAN><\/P><\/DIV><\/DIV><\/DIV>", "portalUrl": "" }