Research & Public Assistance

If you wish to research the location of your property lines, private or commercial, we have the following maps available relating to property lines (boundaries).

Maps & Field Notes: (copies may be purchased at OC Public Works/Central Files: (714) 667-8846) or online at Land Records

  1. Recorded Tracts (Shown on the wall maps and crossed-indexed in Tract Log Book located at the Public Service Counter).
  2. Recorded Parcels (Shown on the wall maps and cross-indexed in Parcel Log Book located at the Public Service Counter).
  3. Recorded Records of Surveys (Shown on the wall maps and cross-indexed in Parcel Log Book located at the Public Service Counter).
  4. Tentative Tracts (Shown in pencil on the wall maps-unrecorded).
  5. Tentative Parcels (Shown in pencil on the wall maps-unrecorded).
  6. Unrecorded Orange County Survey Maps -[S.M.'s] (Contains information usually on road alignments. Shown on the wall maps and indexed on sectional index cards. Also available at Central Files).
  7. Orange County Survey Alignment Books -[OCS] (Contains information on street alignments in the Unincorporated Territory of Orange County. Indexed on cards by street names at the Public Counter).
  8. Orange County Survey Tie Books -[CSTB] (Contains information on street centerline ties in the Unincorporated Territory of OrangeCounty. Indexed on cards by street names at the Public Counter).
  9. California Division of Transportation Field Notes[CALTRANS] (Available only at the local Caltrans Office).
  10. Benchmarks (Contains information Vertical Control in the Unincorporated Territory of Orange County. Indexed at the Public Service Counter. Also available in the Geodetic Unit).
  11. Alpha Named Tracts (Ex. Yorba Tract. Shown on the wall maps and cross-indexed to M.R.L.A.Co. referenced in Central Files).
  12. Rancho Partition Maps (Indexed by name available at Central Files from Microfiche).
  13. U.S. Government Township Plats (Indexed by name; available at Central Files from Microfiche).
  14. U.S. Government Township Plats Notes (Indexed by name; available at Central Files from Microfilm reels).
  15. S.H. Finley Field Book (Contains early County survey data. Indexed and available at the Records Management Unit).
  16. California Division of Transportation [CALTRANS] Contains information on the following:
    - Monument Maps
    - Relinquishment Maps
    - R/W Maps Coordinate
    - Control Maps

    All records are indexed on cards by street names located in Central Files.
  17. Construction Plans (Contains information as it relates to structures or roads built and contracted by the County of Orange. Indexed on cards by street names located in Central Files).
  18. Railroad Maps (Contains information on the early railroad surveys including the AT&SF and SP&PR. Indexed on cards by railroad names located in Central Files).
  19. Sterns Rancho Sectionalized Surveys (Plats located in Central Files).
  20. Aerial Photos (Aerial photos of areas of Orange County. Indexed on cards located in Central Files under AERIAL SURVEYS).
  21. City Boundaries (Contains information on the annexation and incorporation of all cities located in Orange County. (Indexed and filed in the Boundary Unit).
  22. Taxing Districts (Indexed and filed in the Boundary Unit).
  23. Political Districts (Contains information on the boundaries of all Supervisorial Districts. Indexed and filed in the Boundary Unit).
  24. Horizontal Control (Contains information on the Cadastral Points located in the County of Orange. Indexed and filed in the Geodetic Unit).
  25. Flood Control Notes (Contains field notes as it relates to flood control structures located in the County of Orange. Indexed and filed in the Records Management Unit).
  26. Assessor's Maps (Contains information on all parcels taxable in the County of Orange. Available at the Orange County Assessor's Office. Ph: (714) 834-2758).
  27. Property Deeds (Indexed at all Title Companies and at the County Recorder's Office. Ph: (714) 834-2887).
  28. Official Maps (Contains information on early subdivisions of the County. Available at the County Recorder's Office).
  29. Right-of-Way [R/W] Maps (Contains information on R/W held by the County of Orange. Maps and information located in the O.C. Right-of-Way Engineering. Ph: (714) 667-9650).
  30. Original Field Notes (Contains information on early surveys conducted in O.C.Indexed and files in in O.C., indexed & filed in the Records Management Unit).
    a) McBride-with maps
    b) W.K. Hillyard-with maps
    c) D.D. Hillyard-flood notes (OCFCD), level circuits
  31. City Field Notes (Contains information on street centerline tie notes. Available only at the applicable City).
  32. Corner Records (Contains information on property or boundary corners which have been replaced by private surveyors. Un-indexed and available at the Public Service Counter).
  33. Lot Line Adjustments (Contains information on boundary lines which have been adjusted in Unincorporated Territory and approved by the County of Orange. Available at the Central Files on microfiche).
  34. Block and Module [BAM] Index (A file which contains all research available in a given area based on a block and module located a cross referenced for the entire county. See the Public Service Assistant for use).
  35. Highway Lighting District Cities (Information available from the Boundary Unit).
  36. Orange County Street Lighting Assessment District [OCSLAD] (Contains information on street lighting districts. Available from the Boundary Unit).
  37. Tract Improvement Plans (Indexed and available from Central Files).
  38. Street Improvement Plans (Indexed and available from Central Files).
  39. Vacated & Abandoned File Cards (Contains information on all vacated or abandoned areas in the Unincorporated Territory of Orange County and referenced on the wall map as "F#". Available at the Public Service Counter).
  40. Various District Maps (Including those not previously mentioned such as Sewer & Water Districts. Available from Boundary Unit).
  41. Street Name Approval/Change (Files consisting of street names which have been changed within the Unincorporated Territory of Orange County. See the Public Service Assistant/Addressing for help).
  42. Addressing in Unincorporated Areas in Orange County.