Description: This is Delta boundary version 2002.4. It delineates the legal Delta established under the Delta Protection Act (Section 12220 of the Water Code), passed in 1959. This boundary file has been reviewed by a variety of relevant professionals and can be considered acceptable for mapping at 1:24000. The original legal boundary maps obtained from the Delta Protection Commission were compiled by DWR Land & Right of Way sometime in the early 1980s, with one revision made to the original maps in the vicinity of Point Pleasant.Additional notes: The exact accuracy is somewhat uncertain, but can be considered acceptable for mapping within 7.5 Minute USGS map accuracy standards (1:24000 scale). The original topographic maps containing the drawn Delta border were scanned from the Department of Water Resources. Images were registered to 1:24000 USGS DRG's in ArcView (ESRI) utilizing imagewarp extension. The Delta boundary was digitized from the registered images. The original legal boundary maps were based on the legal description in Section 12220 of the Water Code, with ambiguities in the Code addressed by the individuals involved in the mapping project at that time. One revision was made to the original maps in the vicinity of Point Pleasant, and is the only difference between this and the 4.2001 version of the legal Delta boundary Arc/INFO coverage.Published to DWR Spatial Data Library 2/21/2003. Published as an export to geoDB feature class output. Source is DWR Delta Levees Program. These data are distributed as part of the DWR Spatial Data Library. Please advise dataset administrator of any improvements or suggestions for these data, or if additional metadata can be contributed. The State of California, the Department of Water Resources, the Programs, and the individuals working in support of any of the preceding shall have no legal responsibility for providing data to the DWR Spatial Data Library, and shall have no responsibility for any errors or omissions, or for the use or results obtained from the use of this information. User acknowledges and accepts these terms upon receipt of display of any of the contents of any of the files associated with these data. Received from Chico State by DWR Delta Levees Program 5/31/2001. Converted from shapefile into coverage format, converted from Teale Albers into Geographic/NAD83, & rebuilt topology using ArcGIS 8.2, double-precision, by Joel Dudas, DWR Delta Levees Program, 2/2003. The revision between the 4.2001 and the 4.2002 versions reflects a change in the vicinity of Point Pleasant in the east Delta, as shown on modified Delta Protection Commission maps. The line was moved south to the township boundary line, as appropriate, using ArcGIS 8.1 software. During 2001 & early 2002 every effort was made to identify any errors in the underlying data sources, including water district, reclamation district, roads, etc. boundaries. While certain features were not able to be 100% certified, this coverage can be considered to be as accurate based on all of the information available at this time. These uncertainties principally involve obscurity in some of the ancestral source data.
Copyright Text: California Department of Water Resources