,In the Delta Anatomy Mapping Project, all levee anatomies were delineated using slope grids built from available 2007 Delta LIDAR data points. LIDAR data points were converted to digital elevation models and subsequently into slope grids. Thresholds were identified that capture the levee crown, levee landside, levee waterside, ramps and toe ditches. Visual interpretations of slope thresholds were used in conjunction with heads-up digitizing to maintain smooth boundaries at a scale of 1:550. The delineation thresholds were derived from a combination of mapping scale, slope grid resolution and slope thresholds used for each anatomy classification. All anatomy has gone through internal quality control processes to ensure a minimum accuracy of +/- 3 feet.,Anatomy data was further reviewed and tested by DWR for compliance with an interpretive mapping standard of 80% accuracy. Once the levee anatomy was created and accepted, isolation and export of the levee crown was used in conjucture with ET Geowizards to collapse the crown to a singular centerline which details the levee route. This data depicts the levee anatomy at the time of the LiDAR survey (2007) and are only accurate for that time. Users should be aware that temporal changes may have occurred since this data set was created and some parts of this data may no longer represent actual surface conditions. Changes in some linework and attribution were performed by CA DWR Division of Engineering in September, 2018, and current version was posted to DWR GIS Atlas at that time,

Detailed center lines of the Sacramento-San Joaquin levee systems, and broken into singular segments of consistent-attribute sets. This version created from mapping from the 2007 Delta LIDAR. The use of high-resolution LiDAR, and the products derived from it, allow for levee anatomy to be captured for the surveyed area. The resulting data allows for the levee crown sections to be isolated and collapsed to a centerline, detailing the route of the levee system. This data can further be used for levee maintenance and management, flood modeling and prediction, as well as levee inventories. The data are therefore mostly the structural center lines of the levees, with some minor modifications as warranted. In the Delta Anatomy Mapping Project, all levee anatomies were delineated using slope grids built from available 2007 Delta LIDAR data points. LIDAR data points were converted to digital elevation models and subsequently into slope grids. Thresholds were identified that capture the levee crown, levee landside, levee waterside, ramps and toe ditches. Visual interpretations of slope thresholds were used in conjunction with heads-up digitizing to maintain smooth boundaries at a scale of 1:550. The delineation thresholds were derived from a combination of mapping scale, slope grid resolution and slope thresholds used for each anatomy classification. All anatomy has gone through internal quality control processes to ensure a minimum accuracy of +/- 3 feet. Anatomy data was further reviewed and tested by DWR for compliance with an interpretive mapping standard of 80% accuracy.Once the levee anatomy was created and accepted, isolation and export of the levee crown was used in conjucture with ET Geowizards to collapse the crown to a singular centerline which details the levee route. This data depicts the levee anatomy at the time of the LiDAR survey (2007) and are only accurate for that time. Users should be aware that temporal changes may have occurred since this data set was created and some parts of this data may no longer represent actual surface conditions. Changes in some linework and attribution were performed by CA DWR Division of Engineering in September, 2018, and current version was posted to DWR GIS Atlas at that time. This data set was produced by joint effort of DWR and Chico State University. Data were originally developed and supplied by the Geographic Information Center at California State University at Chico, under contract to California Department of Water Resources. DWR subsequently modified the linework in a few places along with the attribution for various levee characteristics of interest. The 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 3.1, dated September 11, 2019. DWR makes no warranties or guarantees — either expressed or implied — 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 sent to GIS@water.ca.gov

"This section identifies those areas in the Delta which because of their resource value should receive special consideration. Those areas...have been classified as Significant Resource Areas. These areas were selected based on several factors, which include significant areas of habitat, the presence of endangered plant or animal species, relative abundance of similar areas within the Delta and State, aesthetic and recreation value, concentrations of archaelogical or historical sites, level of present disturbance, and potential for future disturbance. In evaluating Delta lands to determine Significant Resource Areas, information was obtained from several data sources including consultations with individuals from various State, federal, local, and private organizations. Each area identified as having potential value was inspected using aerial photographs, in the field, or both." -this from the Delta Environmental Atlas, published 7/1979, by USACE. References to the DMRP in the attribute table refer to the Delta Master Recreation Plan. 1979 Delta Significant Resource Areas were made digital by heads up digitizing registered scanned pages from 1979 Delta atlas. About the scanned maps from the Atlas: Digital images were clipped prior to warping to reduce risk of error during processing due to excess background. Digital clipped images were registered to USGS DOQQ's in ArcView 3.x(ESRI) utilizing Imagewarp 2.x extension. 23 October, 2002, Projection: UTM meters zone 10, nad 83. Accuracy within acceptable 7.5 Minute USGS map accuracy standards (1:24000 scale). For this set, the minimum number of control points used was 10 with an average of 12 to 15 points used. The pixel size for this set is 27.0 feet per pixel

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Data contains historical polygons of in-channel islands within the Sacramento San Joaquin Delta. Data consists of merged datasets from 1929, 1940, 1949, 1952, 1995, 2002, and 2017. The 2017 polygons are digitized from the 2017 Delta LiDAR imagery by the Division of Engineering, Geomatics Branch, Geospatial Data Support Section. The older pre-2017 polygons were all digitized by staff in the Delta Levees Program. Data can be queried for a single year or date range using the 'Year' field. Historical data was compiled and merged from datasets provided by the Delta Levees program. Data coverage differs between years. Absences or gaps in historical data may occur. Older acquisitions generally have a smaller footprint than recent imagery acquisitions. The 2017 in-channel islands cover the Legal Delta, and also include Chipps Island.

This dataset, (i06_SingleBeam_Bathymetry) is a feature dataset containing point feature classes with single beam bathymetric data collected by California Department of Water Resources and other entities.

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This dataset, (i06_SingleBeam_Bathymetry) is a feature dataset containing point feature classes with single beam bathymetric data collected by California Department of Water Resources and other entities.

This dataset, (i06_SingleBeam_Bathymetry) is a feature dataset containing point feature classes with single beam bathymetric data collected by California Department of Water Resources and other entities.

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