This data layer represents Sonoma County GIS parcels in the Russian River watershed. Features from the original source data (see Originator information) were selected based on their spatial location within the Russian River watershed in Sonoma and Mendocino counties in California (the study area boundary of the Russian River Watershed Adaptive Management Plan project). This metadata file incorporates much of the information that was available in the metadata of the original source data. This information is indicated in quotation marks. "A distinction should be made with respect to this layer which includes GIS parcels and the official Assessor Parcels residing in the Assessor Map books at the Sonoma County Assessor Office. For official parcel records please contact the Sonoma County Assessor (707)565-1888. These parcels should NOT be represented as survey data, and the official record of survey takes precedence where there are discrepancies. It is the end user's responsibility to check the accuracy of the GIS data by comparing it with the published data from the Sonoma County Assessor / Recorder office. The Sonoma County parcel base was originally compiled from Assessor Parcel maps at a scale of 1:6000. The individual Assessor Parcel maps were enlarged or reduced in size using an electrostatic process to produce the maps at the 1:6000 scale, the maps were then fit together by hand and transcribed on to mylar. The mylar base consisted of 1:6000 USGS base map information typically found on the 7.5 USGS quad series. This base information consisted of Topography, Roads, Section, and Rancho lines to name some. Using this information, the Assessor Parcel maps were fit to the individual 1:6000 scale maps. Each 1:6000 scale map represents 1/6 (quad sixths) of a 7.5 minute USGS Quadrangle series map. In 1998 the State Board of Equalization provided the impetus to produce the Russian River Project for all of Planning Area 4. One aspect required for this project was a digital parcel base for Planning Area 4. This involved the conversion of the 1:6000 mylars with the transcribed parcels on them into a digital version of the parcels. The mylars where scanned and geo-referenced using the base map information originally included with the 1:6000 mylar base. The maps were geo-referenced to a digital version of the USGS 7.5 minute Quadrangle series available from the Teale Data Center. The original projection was California State Plane Zone 2 NAD 1927. County Staff then used AutoCAD software to heads up digitize each 1:6000 scale map in Planning Area 4. A custom application was created and used by GIS staff involving the use of Avenue and ArcView 3.2 to create a point for all the parcels in Planning Area 4, attributes included Assessor Parcel Number. The DWGs were then converted to shapefiles and then converted to ArcINFO coverages, the parcel tags were converted from shapefiles to ArcINFO coverages and the point coverage was merged with the polygon coverage with the IDENTITY command. An exhaustive process was involved to eliminate errors once the DWGs were converted to ArcINFO coverages so polygons could be generated. The coverages were then aggregated using the MAPJOIN command, the original boundary of the 1:6000 scale maps was removed using the REGIONDISSOLVE command to merge adjacent polygons with the same AP number. In 1999 the remainder of the planning areas were converted to digital form following the Russian River Project and the seamless base was completed in 2001. The seamless parcel base was maintained in ArcINFO until the release of ArcGIS 8.3, which included topology tools necessary for its maintenance. The seamless base prior to late 2002 was suitable for 1:100000 scale while the control points (the corners for the 1:6000 scale maps) were suitable for 1:24000 scale. Prior to rectification to the Merrick 2000 orthophotography, the parcel data were derived from 1:6000 scale maps (enlarged from USGS 7.5 minute quadrangle 1:24,000 series) and digitized in California State Plane, Zone II, NAD 27 coordinates (survey feet), but were converted to California State Plane, Zone II, NAD 83 coordinates (survey feet) as part of a rectification process now underway. The parcels used to use the USGS 7.5 minute quadrangle (1:24,000) series for coordinate control, but no guarantee is made for their spatial accuracy. The data were re-projected to NAD 83 coordinates to overlay the orthophotography, but the parcel boundaries will not correspond precisely with features in the images. The parcels were rectified to orthophotography flown in April - May 2000 using geo-referencing tools available in ArcGIS 8.3. This project was completed in July 2005. In general, the parcels meet National Accuracy Standards for 1:24,000 scale maps, and likely exceed that accuracy in urban areas. A complete description of the process is detailed in a series of documents located on a local file server: S:\COMMON\GIS\Documentation\Parcel Rectification & Update Process\Procedure - *. doc. A brief summary is as follows. Individual Assessor Parcel pages or CAD drawings are rectified to the orthophoto. COGO & survey data are used when available and in sufficient quantities to enable the bulk of an Assessor Parcel page to be digitized using said information. Polygons are generated directly from the COGO data, CAD dwg are exported to feature classes, where polygons are then generated, rectified Assessor Parcel pages are vectorized using ArcScan and subsequently polygons are generated. A spatial join is used to assign attributes to the newly generated polygons. Polygons are then assigned an accuracy rank based on source, quality of the fit to the orthophoto, and RMS error encountered during rectification (only the scanned Assessor maps will have and RMS error associated with them). See the fields RANK and DESCRIPTION for information on fit assessment. Areas that have been successfully updated as such have a reasonable expectation of accuracy of +/- 10 and possibly better, areas that have not been updated or are flagged in SCAMP (http://sc-gis/web/scamp/browse.jsp) under the GIS group Projects as Needs Survey Data, the original accuracy assessment of 1:100000 applies."
This data layer was edited from its original source data set for inclusion in the Russian River Watershed Adaptive Management Plan (RRWAMP) and RRWAMP Baseline Watershed Assessment project. The intended use of this data layer in this project is to examine landscape or human factors to promote ecological health and sustainability within the Russian River watershed. "To support visualization, query and analysis of County land records. To document up-to-date records of parcels in Sonoma County. To exhibit a rectified Parcel base to the 2000 Merrick Orthophotography to facilitate maintenance of the base."
ground condition
The user assumes the entire risk related to the use of this data. The developers of this project shall not have any liability to any person or entity with respect to loss or damage caused or alleged to be caused directly or indirectly by information contained in this file. The developers of this project make no warranty, expressed or implied, nor does the fact of distribution of this data constitute such warranty. This data is not for navigational purposes or for use in litigation. In all cases, the user should refer to the original source data and metadata for accuracy, currentness and appropriate contact information. "The County provides the information "as-is", and shall incur no responsibility or liability as to the completeness or accuracy of this information. The County, and other agencies from which the data were sourced, assume no responsibility arising from use of this information by individuals, businesses, or other Agencies. THE MAPS AND ASSOCIATED DATA ARE PROVIDED WITH NO WARRANTY OF ANY KIND, expressed or implied, including but not limited to the implied warranties of merchantability and fitness for a particular purpose. Do not make any business decisions based on these data before validating your decision with the appropriate County or other government office. IMPORTANT POLICY CHANGE (7/1/2004): Except where expressly protected by current State law, the County's GIS data MAY be redistributed or used for derivative works, including maps, reports, graphs and GIS projects, so long as the GIS Data Request Policies and Procedures policy document and the FGDC-compliant metadata are both included. Additionally, the County must be referenced as the original data provider. The user is obligated to describe any or all modifications they have made to the data and must update the corresponding metadata file where appropriate. The user also specifically agrees not to imply that any changes made by the user were approved by the County. In addition to the inclusion of the above information in any re-distribution or use of the data, the following disclaimer must be prominently displayed on all printed maps, digital web pages, or other reproductions utilizing the GIS data: Disclaimer Notice "This information is derived from the County of Sonoma Enterprise GIS Database. The data are not a survey-quality product and the end user assumes the risk of utilizing it. The County of Sonoma does not assume any liability for damages arising from errors, omissions, or use of this information. End users are advised to be aware of the published accuracy, date, compilation methods, and cartographic format as described in the accompanying metadata, and are advised to utilize these data appropriately." This disclaimer shall apply to any authorized or unauthorized transfer of all or parts of the GIS Database."
2619 Paulin Drive
Custom Data requests should be directed to the contact Email address, General questions should be directed to the Contact Voice Telephone and a detailed message left. The call will be directed to the appropriate staff member. Standard data available from https://gis.sonoma-county.org/dataportal.asp
County of Sonoma GIS Central
Parcels numbers in the seamless base are checked weekly against megabyte (the Sonoma County Assessors database) and updates are made accordingly. New or missing parcels are added accordingly. Currently the seamless base is no more than 1 week behind the Assessors Parcel Number inventory. GIS only maintains the parcel features themselves and the APNs associated with them. All other fields are derived from Megabyte.
Polygons must not overlap except when attribute field "LEVEL_" indicates 2, 3, or 4, Polygons must not have gaps
The GIS parcel data are intended for small scale mapping purposes only (i.e., 1:24,000 scale or smaller), and should NOT be represented, in hard copy or digital form, as ground-surveyed data. The GIS street data and orthophotography were generated at a higher level of accuracy and resolution and may be used on maps of 1:600 scales or smaller. Use of these data for any reason other than for planning purposes is NOT recommended, and the liabilities of such usage are the sole responsibility of the entity using this data. A project is underway to catalog the accuracy of parcel data as they are corrected to the orthophotography and will be made available upon completion of the work. The parcels were rectified to orthophotography flown in April - May 2000 using geo-referencing tools available in ArcGIS 8.3. This project was completed in July 2005. In general, the parcels meet National Accuracy Standards for 1:24,000 scale maps, and likely exceed that accuracy in urban areas. Areas that have been successfully updated as outlined in S:\COMMON\GIS\Documentation\Parcel Rectification & Update Process\Procedure - *.doc. have a reasonable expectation of accuracy of +/- 10 feet and possibly better, areas that have not been updated or are flagged in SCAMP (http://sv-gis/scamp4/scamp.jsp) under the GIS group Projects as Needs Survey Data, the original accuracy assessment of 1:100000 applies. Please refer to the attributes, specifically the Rank and Description fields for information pertaining to fit quality assessment.
Not Available
Metadata imported and extensively modified.
2615 Paulin Drive
Dataset copied.
Metadata imported.
This data layer was created for the Russian River Watershed Adaptive Management Plan (RRWAMP) and RRWAMP Baseline Watershed Assessment project through minor editing to the original source data. Data were clipped to the project study area boundary (rr_watershed_bndy.shp) and projected using ESRI's ArcGIS GeoProcessing tools; and renamed to the current file name.
Engineer Research and Development Center
3909 Halls Ferry Road
Metadata imported.
Internal feature number.
ESRI
Assessor Parcel Number (BOOK-PAGE-APN)
Last three characters of an APN with this designation is classified as Unpatented land
Codes for Parcels without APNs
Last three characters of an APN with this designation is classified as State Board of Equalization
Codes for Parcels without APNs
Last three characters of an APN with this designation is classified as a Railroad ROW
Codes for Parcels without APNs
Last three characters of an APN with this designation is classified as a River (water bodies) ROW
Codes for Parcels without APNs
Last three characters of an APN with this designation is classified as Condominium "common areas"
Codes for Parcels without APNs
Last three characters of an APN or areas with gaps in legal descriptions or lots sold of record, but not on the roll
Codes for Parcels without APNs
Last three characters of an APN with this designation is classified as Wildcat areas
Codes for Parcels without APNs
Last three characters of an APN with this designation is classified as an out of county parcel which could mean a parcel that is in Sonoma County but is assessed by another county
Codes for Parcels without APNs
Last three characters of an APN with this designation is classified as a Road ROW
Codes for Parcels without APNs
Feature geometry.
ESRI
Indicates if a parcel was adjusted after integration into seamless parcel base
Parcel has been adjusted after integration into seamless parcel base
Type of change performed on parcel.
GIS/Assessor
Technical Review
A change involving position or shape of the parcel.
Feature geometry.
ESRI
Not Ranked
Survey Analyst Points, GPS Subdivisions
GPS, Record of Survey
COGO received from outside agency, COGO by GIS Staff
2d Map, Keyed CAD Drawing
Good Fit, RMS < 4
Good Fit RMS > 4
Fair Fit, RMS < 4
Fair Fit, RMS > 4
Poor Fit (RMS not applicable)
PRMD Parcel Features warped to fit the orthophoto
Pre-Rectification State of Parcels
City Based Rectification of parcels to orthophoto
Fit and Accuracy Assessment
Survey Analyst Points, GPS Subdivisions
GPS, Record of Survey
COGO received from outside agency, COGO by GIS Staff
2d Map, Keyed CAD Drawing
Good Fit, RMS < 4
Good Fit RMS > 4
Fair Fit, RMS < 4
Fair Fit, RMS > 4
Poor Fit (RMS not applicable)
PRMD Parcel Features warped to fit the orthophoto
City Based Rectification of parcels to orthophoto
No Rank
2615 Paulin Drive
Data requests should be directed to the contact Email address, General questions should be directed to the Contact Voice Telephone and a detailed message left. The call will be directed to the appropriate staff member.
Except where expressly protected by current State law, the County's GIS data MAY be redistributed or used for derivative works, including maps, reports, graphs and GIS projects, so long as the GIS Data Request Policies and Procedures policy document and the FGDC-compliant metadata are both included. Additionally, the County must be referenced as the original data provider. The user is obligated to describe any or all modifications they have made to the data and must update the corresponding metadata file where appropriate. The user also specifically agrees not to imply that any changes made by the user were approved by the County. In addition to the inclusion of the above information in any re-distribution or use of the data, the following disclaimer must be prominently displayed on all printed maps, digital web pages, or other reproductions utilizing the GIS data: Disclaimer Notice "This information is derived from the County of Sonoma Enterprise GIS Database. The data are not a survey-quality product and the end user assumes the risk of utilizing it. The County of Sonoma does not assume any liability for damages arising from errors, omissions, or use of this information. End users are advised to be aware of the published accuracy, date, compilation methods, and cartographic format as described in the accompanying metadata, and are advised to utilize these data appropriately." This disclaimer shall apply to any authorized or unauthorized transfer of all or parts of the GIS Database.
Download current version of data: http://www.russianriverwatershed.net/Content/10006/GISDataforDownload.html "Data may be obtained from the County of Sonoma GIS data portal; point your browser to https://gis.sonoma-county.org/dataportal.asp to obtain data via downloaded zip file. Parcel data is typically updated on a monthly bases, other data is updated as needed. All requests for custom GIS data are handled on a first-come, first-serve basis. Make requests for data directly to the GIS Request Line at (707) 565-3819 or via E-mail at gis@sonoma-county.org. Please include your contact information, including name, agency, telephone number, and E-mail address. Requests for custom data or project specific work are charged at GIS Central's hourly rate. See the separate document; Sonoma County GIS Central Data Distribution Fees. Requests are normally shipped within 10 business days. Purchaser will be invoiced by the Sonoma County Auditor's Office."
All requests for GIS data are handled on a first-come, first-serve basis. Requests for data in Standard Format (see below) are normally shipped within 10 business days. Custom requests are filled in a schedule mutually agreed upon between the County and the customer. Make requests for data directly to the GIS Request Line at (707) 565-3819 or via E-mail at gis@sonoma-county.org. Please include your contact information, including name, agency, telephone number, and E-mail address. Data are typically provided on CD(s) for a processing fee that covers time and materials required to process the request. Requests for custom data or project-specific work are charged at GIS Central's hourly rate. Purchaser will be invoiced by the Sonoma County Auditor's Office (http://www.sonoma-county.org/auditor/). NOTE: The County is in the process of developing an Internet site (https://gis.sonoma-county.org/) to enable members of the public to download the Standard Format products (i.e., vector data and aerial photography) free of charge. This site is tentatively scheduled to be published in the second quarter of the current fiscal year (i.e., Autumn 2004). Appendix A Sonoma County's data policy is governed by California's State Public Records law. In particular, note the following sections from California's Government Code § 6250 et. seq: § 6251 (d) - "Public records" includes any writing containing information relating to the conduct of the public's business prepared, owned, used, or retained by any state or local agency regardless of physical form or characteristics. § 6253 (b) - Except with respect to public records exempt from disclosure by express provisions of law, each state or local agency, upon a request for a copy of records that reasonably describes an identifiable record or records, shall make the records promptly available to any person upon payment of fees covering direct costs of duplication, or a statutory fee if applicable. Upon request, an exact copy shall be provided unless impracticable to do so. § 6253.9 (1) - The agency shall make the information available in any electronic format in which it holds the information. (2) - Each agency shall provide a copy of an electronic record in the format requested if the requested format is one that has been used by the agency to create copies for its own use or for provision to other agencies. Direct costs of duplication shall include the costs associated with duplicating electronic records. § 6254 - Exemptions that shall not be construed to require disclosure of records. (Specific exemptions protecting individual privacy and community security are enumerated.) The purpose of the Sonoma County Enterprise GIS is to provide geographic information in a central location to decision-makers across County departments. Data not residing in the Enterprise GIS, but available from a County department or other government agency, are governed by the rules and regulations attributable to the agency in question. The County is under no obligation to make data available which is proprietary in nature (i.e., licensed from a third party). Requests for such data will be referred to the appropriate data owner.
2615 Paulin Drive
Data requests should be directed to the contact Email address, General questions should be directed to the Contact Voice Telephone and a detailed message left. The call will be directed to the appropriate staff member.