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County boundaries California

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Publication Date

Summary

In late 1996, the Dept of Conservation (DOC) surveyed state and federal agencies about the county boundary coverage they used. As a result, DOC adopted the 1:24,000 (24K) scale U.S. Bureau of Reclamation (USBR) dataset (USGS source) for their Farmland Mapping and Monitoring Program (FMMP) but with several modifications. Detailed documentation of these changes is provided by FMMP and included in the lineage section of themetadata. A dataset named cnty24k97_1 was made available (approximately 2004) through the California Department of Forestry and Fire Protection - Fire and Resource Assessment Program (CDF - FRAP) and the California Spatial Information Library (CaSIL). In late 2006, the Department of Fish and Game (DFG) reviewed cnty24k97_1. [...]

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Extension: Counties_CA.zip
Counties_CA.sd
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Material Request Instructions

Bureau of Reclamation County Line Modifications (Update)

6 May 2009

Since the time of the last update of the county data by the Department of Conservation's Farmland Mapping and Monitoring Program (DOC-FMMP) in July 1997, the California Mapping Coordinating Committee (CMCC) has requested that the California Department of Forestry and Fire Protection (CAL FIRE) resume stewardship of the statewide county boundary data (originally digitized by the US Bureau of Reclamation).  For the past few years CAL FIRE has received suggestions for enhancements to the county data from multiple sources.  Our latest update to county lines is based on comments and input from DOC-FMMP, CA Department of Fish and Game, CA Board of Equalization, Kern County, Orange County, and Ventura County.  Data editing was performed by both Department of Fish and Game and CAL FIRE.  All changes are described below.

When a request was made to change a county line, CAL FIRE looked at two spatial sources: parcel data from counties, and the set of scanned USGS 7.5' topo quads (aka 24k DRGs) on the California Spatial Information Library (CaSIL).  In addition, CAL FIRE also reviewed the legal text for county boundary descriptions (Government Code Section 23100-23158) on the California Legislative Information website:
http://www.leginfo.ca.gov/cgi-bin/calawquery?codesection=gov&codebody=23101

Documentation for legal boundary changes was also provided to CAL FIRE by CA Board of Equalization.

Ventura-Kern and Ventura-Santa Barbara Counties

Background

The two county line sections in question are the western edge of Ventura County (shared with Santa Barbara County) and one of the northern edges of Ventura County (shared with Kern County).  Ventura County Fire Protection District contacted CAL FIRE to let us know that the Bureau's line did not line up well with their county parcel data.  Parcel data from Ventura County, Santa Barbara County, and Kern County aligned well with each other, but did not align well with the Bureau's county lines.  Because Ventura County FPD needs CAL FIRE data to align with their data, Ventura County FPD requested that we adjust the Bureau's line.

Sources Referenced

Kern County Parcel Data
Santa Barbara Parcel Data
Ventura County Parcel Data
Ventura County Fire Protection District

Result

After considering the sources reviewed, CAL FIRE decided to adjust the two county line sections that Ventura County FPD requested for us to adjust.  The need for county boundary lines that agree with the county linework used by local governments is becoming more critical as more and more local governments are using GIS data from the state.  Parcel data from the three counties does not align perfectly (node-to-node) from county to county.  However, all 3 counties' parcel data illustrate the northwest corner of Ventura County as being about 0.1 mile west of where it is shown on the Bureau file.  In addition, Kern parcel data and Santa Barbara parcel data illustrate one of the northern edges of Kern County as being 0.5 mile north of where it is shown in the Bureau file.

CAL FIRE edited the Bureau's line by "snapping" the Bureau's northwest corner of Ventura County to the northwest corner of Ventura County's parcel data.  CAL FIRE also used Ventura County's parcel data as a basis for snapping the northern section of the Bureau's line by snapping the nodes of the Bureau's line to the nodes of the parcel data.

Lake-Mendocino-Sonoma Counties

Background

The boundary in question is the southeast corner of Mendocino County shared with Lake County and Sonoma County.  Department of Fish and Game observed that the Bureau line did not line up with the scanned USGS 7.5' quad on CaSIL.

Sources Referenced

USGS 7.5' paper quad, "The Geysers" 1975
USGS 7.5' scanned quad, "The Geysers" 1993
Lake County parcel data
Mendocino County parcel data
Sonoma County parcel data

Result

After examining the 1975 USGS 7.5' quad and the 1993 USGS 7.5' quad CAL FIRE determined that USGS changed the way the boundary was drawn in the 1993 quad, which was released after the Bureau digitized the county lines into GIS format back in 1992.  This is not considered a legal change because the Public Land Survey System (PLSS) lines (which form the basis for the county boundary lines in this area) are represented as dashed lines in both quads, which means neither version is up to National Map standards.  However, after comparing parcel data from Lake, Mendocino, and Sonoma counties to the two USGS quads, it is clear that these counties based their county lines on the more recent 1993 quad.  CAL FIRE adjusted the Bureau line for the southeast corner of Lake-Mendocino-Sonoma in order to match both the parcel data and the latest USGS quad.

Fresno-Merced Counties (legal boundary change - January 1, 2008)

Background

On December 31, 2007 a Merced County press release announced that a portion of the Merced-Fresno county line would change on January 1, 2008 by officially moving a portion (6.52 sq mi or 4,175 ac) of Fresno County into Merced County.  The purpose of the change was to enhance access to emergency services for local residents in the area south of Dos Palos.

Sources Referenced

Merced County Press Release (12/31/07)
Fresno Local Agency Formation Commission Report (12/5/07)
Vicinity Map of boundary change (in LAFCo report)
California Board of Equalization documents
Fresno County parcel data
Merced County parcel data

Result

The vicinity map included in the LAFCo report showed which Fresno parcels would be moved into Merced County.  CAL FIRE adjusted the Bureau line to the new county line by using the vicinity map and Fresno County parcel data as guidelines.

San Bernardino-Riverside Counties (legal boundary change - 2003)

Background

California Board of Equalization reported a minor legal boundary change along the southern boundary of San Bernardino County (near the southwest corner of San Bernardino County) shared with Riverside County.  The section of the boundary that changed is within unincorporated area that is west of the city of Rialto.  Two former Riverside parcels were moved into San Bernardino and two former San Bernardino parcels were moved into Riverside.

Sources Referenced

California Board of Equalization documents
Riverside County parcel data
San Bernardino County parcel data

Result

California Board of Equalization provided CAL FIRE with copies of documents confirming the boundary change.  Parcel data from San Bernardino and Riverside Counties also confirmed the change.  CAL FIRE adjusted the Bureau line to match with the parcel data.

Yuba-Placer-Sutter Counties (legal boundary change - 2002)

Background

California Board of Equalization reported an annexation by city of Wheatland near the boundary of Yuba County.  This annexation indicated that a legal boundary change had occurred that affected Yuba, Placer, and Sutter Counties-parts of Placer and Sutter had been annexed by Yuba.  Board of Equalization later provided CAL FIRE with the documentation that confirmed the county boundary changes.

Sources Referenced

California Board of Equalization documents
Yuba County parcel data
Placer County parcel data
Sutter County parcel data

Result

The documents provided by Board of Equalization confirmed the boundary change among the three counties.  In addition, the parcel data from the three counties also confirmed the change.  CAL FIRE adjusted the Bureau line to match the parcel data, using Yuba county parcels as the main guideline. 

Kern-Los Angeles Counties (legal boundary change - 2001)

Background

Kern County Fire Department (KCFD) reported a boundary change in northwest Los Angeles County that had not been reflected in the Bureau county line.  The part of the boundary in question was a segment shared between Kern County and Los Angles County.

Sources Referenced

State of California Legal text description of Los Angeles and Kern County boundary lines
California Board of Equalization documents
Los Angeles County parcel data
Kern County parcel data

Result

After examining multiple sources CAL FIRE confirmed that KCFD was correct.  The Los Angeles County parcel data and Kern County parcel data both reflect the boundary change.  In addition the legal text for county boundary descriptions from the California Legislative Information website also confirms the change.  CAL FIRE adjusted the Bureau line so that it would conform to the boundary shown in Kern County's parcel data. 

Orange-Riverside Counties (legal boundary change)

Background

During their review of the Bureau's county lines in 2006, Department of Fish and Game observed an inconsistency along the Orange-Riverside boundary when comparing the Bureau's line with the county line in co100a from the former Teale Data Center Solutions Group.  The area in question is in southwest Riverside County.  

Sources Referenced

State of California Legal text description of Orange and Riverside Counties
co100a shapefile (aka 100k counties) from the former Teale Data Center GIS Solutions Group
Orange County parcel data
Riverside County parcel data

Result

Department of Fish and Game (DFG) confirmed that a boundary change had occurred by checking the county boundary legal text on the California Legislative Information website.  DFG adjusted the Bureau line to match co100a, which was already consistent with the legal text description.  CAL FIRE also checked the legal text and concurred that the change was accurate.  CAL FIRE also compared the DFG line adjustment with parcel data from Orange County and Riverside County and determined the alignment with parcel data was good.  So CAL FIRE made no further adjustments to DFG's adjustment in this area.

Orange-Los Angeles Counties (legal boundary change - August 29, 1999)

Background

The Orange County Local Agency Formation Commission (LAFCo) contacted CaSIL in 2008 to report that the Bureau's line did not reflect a change along the Orange-Los Angeles County boundary that occurred on August 29, 1999.  The area in question is along the northern boundary of Orange County and shared with the southern boundary of Los Angeles County.

Sources Referenced

Orange County Local Agency Formation Commission documents
California Board of Equalization documents
Los Angeles County parcel data
Orange County parcel data

Result

Documentation provided by the Orange county LAFCo provided clear evidence of the boundary change in 1999.  CAL FIRE found the area in question by comparing the Bureau's county line to parcel data for Orange County and Los Angeles County.  The Orange County parcel data clearly showed the parcels that Orange County had annexed from Los Angeles County.  CAL FIRE adjusted the Bureau line to match the county line as shown by Orange County parcel data.

Orange County (man-made island)

Background

During a review of the county lines in 2008, Department of Conservation observed that the Bureau's county lines for Orange County did not include a man-made island in the Huntington Harbor/Seal Beach area.

Sources Referenced

Imagery from the National Agricultural Imagery Program (NAIP)

Result

CAL FIRE digitized the missing island based on NAIP data.

San Francisco County (along mouth of bay)

Background

Department of Fish and Game observed that the Bureau's western boundary for San Francisco County followed the shoreline and did not include the mouth of the bay between Pt. Reyes (at the southern tip of Marin County) and Pt. Lobos along the northwest shore of San Francisco County.

Sources Referenced

State of California Legal text description of San Francisco County

Result

Department of Fish and Game confirmed that the bay opening is part of San Francisco County by checking the county boundary legal text on the California Legislative Information website.  DFG adjusted the western boundary to include the bay opening.  CAL FIRE and DOC-FMMP have both concurred with this change and CAL FIRE has not made any further adjustments to DFG's adjustment.

Santa Barbara County (offshore islands)

Background

During their review of the Bureau's county lines in 2006, Department of Fish and Game observed that the Bureau's county lines for Santa Barbara did not include Anacapa and Santa Barbara islands.

Sources Referenced

coastn27 coverage from State Lands Commission

Result

Department of Fish and Game added the missing islands using previously-digitized coastline data (coast27 of State Lands Commission origin).  Both CAL FIRE and DOC-FMMP concur with this change and have not made any further changes to the DFG linework.

Changes other than linework

During their 2006 update of the data, Department of Fish and Game created a multipart version of the counties feature class (using region topology in coverage format), which has 58 multipart features (one record for each county in the attribute table).  CAL FIRE updated linework in both the single part feature class and the multipart feature class.  Both of these feature classes can be found in the File geodatabase.

Department of Fish and Game also added three additional attributes (ABBREV, ABCODE, and FIPS) to both versions of the feature class.  CAL FIRE has kept these attributes, but renamed the FIPS field to ANSI (American National Standards Institute) to reflect the Federal Government's new name for FIPS.  In addition to keeping the attributes from Department of Fish and Game, CAL FIRE has added an ISLAND attribute, which indicates with a Y or N if a feature is an island (making it easy to remove them from display).  CAL FIRE has also updated the ABBREV field to reflect the new county abbreviations recommended by CMCC in April 2009.

In the line feature class, CAL FIRE has also added a TYPE attribute, which classifies the lines into 5 categories: coast, county, island, stateline, and Mexico.  The line feature class includes a cartographic representation, which symbolizes the county lines based on the TYPE categories.

Purpose

This dataset was created so that a common boundary dataset could be used by multiple agencies. This layer provides an initial offering as "best available" at 1:24,000 scale. Additional improvements, including a review of data sources for the coastline, can be added over time based on interagency review and agreement on proposed changes.

Rights

The State of California and the Department of Forestry and Fire Protection make no representations or warranties regarding the accuracy of data or maps. The user will not seek to hold the State or the Department liable under any circumstances for any damages with respect to any claim by the user or any third party on account of or arising from the use of data or maps. There are no restrictions on distribution of the data by users. However, users are encouraged to refer others to the Department of Forestry and Fire Protection to acquire the data, in case updated data become available.
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Communities

  • Pacific Southwest Region, Region 8
  • U.S. Fish and Wildlife Service

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Data source
Input directly
California Department of Forestry and Fire Protection - FRAP, 2009, based on datasets created by : U.S. Bureau of Reclamation, California Department of Conservation, California Department of Fish and Game

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