Select a language:


Field Survey Section

No, the Field Survey Section only performs surveys on County owned land, roads, and flood control channels, also Newport Bay, Dana Point Harbor, and Sunset Beach Marina.  Information about having a private survey done or how to obtain a Professional Surveyor to survey your own lot or boundary is available at the County Service Center or by calling  (714) 967-0852. 

Please call Wade Weaver, Deputy County Surveyor, Field Unit, at (714) 955-0151.  We certainly appreciate being notified when a survey monument is disturbed, or if one is about to be disturbed.

You may contact Wade Weaver, Deputy County Surveyor, Field Unit, at (714) 955-0151. 

Landbase Information Systems

In 1989, the Southern California Gas Company contacted Orange County to see if we would be interested in entering a partnership to create a parcel-level digital basemap.  The County of Orange then entered into such a partnership.  The County provided the land records (maps, deeds, horizontal control, and conversion quality control) and the Gas Company was responsible for converting these records into digital form.

The County of Orange Digital Landbase Mapping System "OC Landbase", or Land Information System (LIS), is a very accurate parcel-level digital basemap containing over 687,000 subdivision parcels that are linked to text information (attributes) such as Assessor Parcel Number, owner name and street address. The OC Landbase also contains graphic information for street centerlines and various districts.

The OC Landbase is currently stored in an ESRI Parcel Fabric dataset and is maintained using ESRI Parcel Editor. Going beyond the requirements of the California Public Records Act, the County of Orange translates and releases subject OC Landbase data in ESRI shape file format annually.

Effective January 12, 2012, the County revised its licensing process and fee schedule for the public to obtain OC Landbase data, per Orange County Board of Supervisors Resolution 11-196. Licensed attribute information includes (where available) a file of APN indexed owner name, situs address, city, mailing address, land value, improvement value, net value, property type and legal description.

Contact Maria Abrogar at (714) 967-0815 or for questions regarding Landbase data licensing.

Contact Mark Liu at (714) 967-0831 or for questions regarding Landbase data content.

Contact Dennis Tebo at (714) 967-0832 or for questions regarding Landbase data maintenance.

There are several private companies that include OC Landbase data in the spatial data services that they provide. These firms may also provide services that are customized for individual needs.

A link to view the Board Resolution 11-196 and the new OC Landbase license agreement template that govern the licensing and usage of the OC Landbase, is here:
Board Resolution 11-196 

Yes, the OC Landbase contains an independent compilation of land records, other spatial data, and copyrighted matter.  Any licensee of said data shall take all reasonable precautions to protect and maintain the confidentiality of the OC Landbase. 

Yes, the County of Orange Landbase is registered to the California Coordinate System, North American Datum 83.  The foundation of this system is the County Geodetic Control Network, consisting of over 2,700 control points on an approximate half-mile grid.  This strong foundation makes the County Landbase very accurate, and allows new map information to be added, without losing accuracy.

The County Landbase is updated on a regular basis.  Final tract maps and parcel maps are updated to the Landbase within 4-6 weeks of recordation.  Other land information such as records-of-survey, lot line adjustments, deeds, and boundary annexations are also posted to the Landbase on a regular basis.

Yes, the Landbase Maintenance section maintains several district features. These include census tract, city, college, school, irrigation, judicial and supervisorial district boundaries.  

Map Checking

Upon submitting a map for review, a screen check of the map is performed to verify that the map is in compliance with the Orange County Board of Supervisor's Ordinance 3984.  The Ordinance requires that the boundary is tied to two OCS GPS Horizontal Control points.  Further, the Ordinance requires that the map's Basis of Bearings be derived from the inverse between the two points. 

The map submittal package is reviewed to ensure that necessary reference materials have been submitted (i.e. title reports, traverse closures, underlying recorded maps, tie notes, deeds, official records).  

Maps are logged and checked by the date received.  Once the map checker has examined the map for boundary determination, drafting standards, and mathematical correctness, the map checker will write a correction letter and submit it for review by a Licensed Land Surveyor, prior to it being returned to the submitter for review and necessary corrections. 

For all map submittals or number issuance, create an account at

For any questions concerning map submittals, please call our Public Counter at, (714) 967-0852.

When the boundary of a map has been determined to be established correctly, and there are few corrections left to be made; the check letter will notify the Surveyor / Engineer that if no further changes to the boundary or lots as configured are made, it will not be necessary to submit another check print.   The Surveyor / Engineer may then submit the original mylars for recordation.

Once the City Council and City Engineer's Statements have been completed, all record owners have signed, and the map has been Notarized; it is now the responsibility of your Title Company to process the map from the City Engineer’s Office to the County Treasurer-Tax Collector’s Office for verification of tax payment or bond. 

Once the County Treasurer-Tax Collector has signed the certificate, the Title Company is responsible for processing the map to the County Surveyor’s Office for final review, prior to recordation.

This process can vary depending on whether the map is located in a "City" or in the Unincorporated Territory of the "County" of Orange.  If the map is a City map, it will be reviewed to verify that the revisions requested in the last correction letter are complete.  If not, we will notify the Surveyor / Engineer of any deficiencies and wait for their response.  When all corrections have been completed, the map will be forwarded for signature by the County Surveyor.

The map will then be sent to make duplicate mylars of the originals, and then sent to the County Recorder's Office for recordation.  Under ideal conditions, this process can be completed within 5 working days.

If this map lies within the Unincorporated Territory of the County of Orange, all steps mentioned above will be followed, except that once the County Surveyor signs the map, it will be forwarded to the County Board of Supervisor’s for approval (if applicable).  The map will then be sent for a duplicate and then sent to the County Recorder’s Office for recordation. 

Note: The Recorder’s Office normally records a map within a few days, but by law, they have up to 10 working days to post the recordation.

The following is a listing of those common items:

  • Title report discrepancies
  • Outdated title report (older than 30 days)
  • Digital file not submitted
  • City Engineer seal missing on Parcel Maps (66450 SMA)
  • All bonds, agreements, and non-interference letters not completed on County Maps

The deposit required when a map is submitted for first check is based upon a deposit needed for a first and final review of a map. If the map is resubmitted for re-examination, there may not be sufficient funds to cover the expense for the additional reviews, an additional deposit may be needed.  Any money not used will be refunded.

Call Margarita Espinoza, at (714) 967-0847, to help you with the status of your map.

Yes, all maps submitted after January 1994, must be tied to the GPS Control points.  The bearing shown in the Basis of Bearings Statement and what the map bearings are relative to, must be the bearing as calculated between the two GPS Control points.  All subdivision mapping must be tied into the California Coordinate System (CCS). 

Geodetic Control

You can call the Geodetic Unit at (714) 967-0848.  It is very important and appreciated that you notify us.  This information is used to update the database, which we would like to keep as current and accurate as we can.

When the original 2050 GPS horizontal control network was done in 1990, Monument Records were prepared on all of the stations.  These records can be found at the OC Survey front counter located at the County Service Center (601 North Ross Street, Santa Ana, CA).  These records (Tie Notes) contain a simple sketch with the local curb ties with their respective measured distances.  

Monuments can be reset from these ties as long as the tie distances agree within an acceptable tolerance.  Additionally, Record of Surveys were recorded for all GPS points. 

UPDATE: Local ties are now filed as Corner Records and may also be found at Land Records

All control point information can be accessed on the OC Survey website via the "Orange County Public Records Retrieval System" located at Land Records.  Select “Geodetic” on the menu located on the left side.

The NGVD 29 and NAVD 88, OCS 1995 adjustments are both referenced to the geoid (mean sea level). Because of the errors in the leveling and distortion from the sea surface topography, NGVD 29 is not an accurate sea level datum. Since the adjustment was warped to fit the local tidal stations, NGVD 29 does most closely fit "local mean sea level". NAVD 88 is a more accurate orthometric height because the errors that NGVD 29 contain are not present. The two datum’s relative differences between each benchmark should be equal. Certain areas will differ due to the constrained benchmarks in each adjustment. Benchmarks held fixed in the NAVD 88 adjustment are not the same as the benchmarks held fixed in the NGVD 29 adjustment. Of course, the absolute difference between each datum will differ greatly, average 71 cm (2.3 ft.). County of Orange, Caltrans, and Federal Emergency Management Agency (FEMA) are using NAVD 88. The American Congress on Surveying and Mapping and Federal Geodetic Control Subcommittee recommends using NAVD 88. Switching from NGVD 29 to NAVD 88 vertical datum is similar to switching from NAD27 to NAD83 horizontal datum. As to what vertical datum should be used, it is up to the Surveyor and the requirements of each project. NGS will only be maintaining the NAVD 88 network in the future. The OCS 1995 adjustment will be the last NGVD 29 adjustment that the County of Orange will maintain. 


1991.35 is the year decimal equivalent of May 8th, 1991. This date represents when the horizontal stations were surveyed and the published coordinates represent where the stations were relative to each other on that date.

"The National Geodetic Vertical Datum of 1929" (NGVD29) which is the name, after May 10, 1973, of (the) Sea Level Datum of 1929." "Sea Level Datum of 1929: A vertical control datum established for vertical control in the United States by the general adjustment of 1929." "Mean sea level was held fixed at the sites of 26 tide gauges, 21 in the U.S.A. and 5 in Canada. The datum is defined by the observed heights of mean sea level at the 26 tide gauges and by the set of elevations of all benchmarks resulting from the adjustment. A total of 106,724 km of leveling was involved, constituting 246 closed circuits and 25 circuits at sea level." "The datum (was) not mean sea level, the geoid, or any other equipotential surface. Therefore, it was renamed, in 1973, the National Geodetic Vertical Datum on 1929." The North American Vertical Datum of 1988 (NAVD 88) is the vertical control datum established in 1991 by the minimum-constraint adjustment of the Canadian-Mexican-U.S. leveling observations. It held fixed the height of the primary tidal benchmark, referenced to the new International Great Lakes Datum of 1985 local mean sea level height value, at Father Point/Rimouski, Quebec, Canada. Additional tidal benchmark elevations were not used due to the demonstrated variations in sea surface topography, i.e., the fact that mean sea level is not the same equipotential surface at all tidal benchmarks. For further information, please visit the NOAA website.

We do not have the elevation to your property but we can give you a benchmark in your area that can be used by a surveyor to establish an elevation on your property.

Very simply stated, NGVD29 is very close and can be considered Mean Sea Level. NAVD88 has no relationship to Mean Sea Level in this area. NAVD88 differs from NGVD29 by about 2.34' in Orange County.

By following the proper procedures which are outlined in the document "Procedures for Establishing the Mean High Water Line Boundaries" prepared by the Geodetic Unit. This document can be used as a guideline and is in no way the only correct way to establish the Mean High Water line. 

Right of Way Engineering

ROWE will provide recording information for easements acquired and processed through OC Public Works, but copies must be obtained from the County Recorder's Office located at 12 Civic Center Plaza, Santa Ana, CA,  phone (714) 834-2500.

The County only tracks County related public easements.  You need to refer to your Title Policy for a list of easements that burden or encumber your property.  If a County easement affects your property, we can give you specific information on it.  We can also show you how to get specific information on other easements over your property.

Contact Ray Rivera, Senior Land Surveyor at (714) 667-9657.

Copies of Maps and Surveys are available at the Public Counter, 601 N. Ross St., Santa Ana.  Call (714) 967-0852.   See also, Land Records.

Yes, copies are available for most of these items for a nominal cost. Contact Right-of-Way Engineering (ROWE), Senior Land Surveyor, at (714) 667-9657.

No, that information is available through Caltrans or the city in question.

Central Files (714) 667-9766.

Improvement Plans. Please call (714) 667-9766. 

You may also wish to contact a utility locator service such as DigAlert ( or call 811).