Caltrans right of way maps are the state’s official record of what land it owns, controls, or holds easements over along every California state highway, and you access them by identifying your location on the highway’s postmile system and then requesting the Record Map from the Caltrans district office covering that segment, either online where the district has a map viewer or by contacting the district’s Right of Way Engineering office directly.1California Department of Transportation. Right of Way Maps and Survey Records Reading one takes some familiarity with surveying conventions, but the information you need for most property, permit, and boundary questions is all on a single sheet once you know where to look.
What a Record Map Shows
A Right of Way Record Map presents the current status of all real property under Caltrans control along a stretch of highway: land owned outright, easements, access rights, and excess parcels the state acquired but does not need for the road itself.2California Department of Transportation. Right of Way Manual Chapter 6 – Right of Way Engineering California’s Streets and Highways Code requires these maps to show boundaries with enough precision that a surveyor can retrace them on the ground.3California Legislative Information. California Code Streets and Highways Code 863 – Establishment of Boundaries That legal weight is what makes the Record Map the go-to document for title companies, surveyors, adjacent owners, and anyone applying for a permit.
Caltrans produces other R/W mapping products too. Appraisal Maps are working documents used during acquisition, Resolution of Necessity Maps accompany condemnation actions, and Court Exhibit Maps show “before” and “after” conditions for condemnation trials.4California Department of Transportation. Plans Preparation Manual Chapter 4 – Right of Way Engineering Mapping For a property owner or permit applicant, the Record Map is almost always the right one to ask for.
Find Your Location by Postmile
Caltrans does not organize its maps by street address. Every point on a state highway is identified by a postmile, measured in miles from the point where the route enters a county or from the start of the route.5California Department of Transportation. Postmile Services A postmile has three parts: a county code (such as SAC for Sacramento or SB for Santa Barbara), a route number, and a postmile value.
The Caltrans Postmile Query Tool at postmile.dot.ca.gov converts geographic coordinates into postmiles and validates postmile values you already have. Watch for prefix letters attached to postmile values: R marks a first realignment, T a temporary connection, M and N later realignments, and S a spur.5California Department of Transportation. Postmile Services The same numeric value with a different prefix points to a different piece of ground, so a missed prefix can send you to the wrong map entirely.
Where to Get the Map
Record Maps and Appraisal Maps are held by each Caltrans district, and the starting point is the Right of Way Maps and Survey Records page at dot.ca.gov/programs/right-of-way/rw-maps-surveys-records.1California Department of Transportation. Right of Way Maps and Survey Records Some districts have digitized their full collection into an online viewer. District 4, covering the Bay Area, hosts its R/W and survey documents through an ArcGIS “Maps on Demand” web application where you can search by route, county, and postmile range and download PDFs.
Other districts may not have a public viewer, in which case you contact the district Right of Way office and give them the route, county, and postmile range. Older maps that have not been scanned live in district files and typically require a direct request.
For surveyors, engineers, and planners integrating boundary data into their own software, Caltrans publishes right of way geospatial data in Shapefile, GeoJSON, KML, and CSV formats, with access through ArcGIS REST API and OGC Web Map Service protocols.6Data.gov. Right of Way (Feature Layer) These datasets are useful for overlays but do not replace the detailed Record Map.
Reading the R/W Line and Datum
The most important feature on the map is the right of way line itself, typically drawn as a heavy solid line marking the outer limit of the state’s property interest. Everything inside belongs to or is controlled by Caltrans. Everything outside is private or locally owned.
Every Record Map identifies the datum used for its coordinates: either NAD 1927 or NAD 1983, along with the specific adjustment and zone.2California Department of Transportation. Right of Way Manual Chapter 6 – Right of Way Engineering If you are hiring a surveyor to place the R/W line on the ground, confirm the surveyor is working in the same datum as the map. A mismatch between NAD 27 and NAD 83 can move coordinates by several feet, which is a serious problem at a property boundary.
Reading Access Control Ticks
Access control is the map feature most likely to catch a property owner off guard. Freeways carry full access control, meaning no private driveways or direct connections. Expressways may have partial access control.7Justia Law. California Streets and Highways Code 250-257 – The California Freeway and Expressway System
On the Record Map, restricted access appears as small perpendicular marks called access denial ticks along the R/W line. Where access is allowed, the map shows openings with their size and position tied to the R/W line.4California Department of Transportation. Plans Preparation Manual Chapter 4 – Right of Way Engineering Mapping If the state acquired something less than full access rights, the map notes the specific restriction, such as “Vehicle Access Restrictions.”
The practical consequence: if the map shows access denial ticks along your highway frontage, no new driveway onto that highway will be permitted, no matter what local zoning allows. Right of Way Engineering staff verify access control on every Record Map through cross-checks with Construction and Design and field reviews.2California Department of Transportation. Right of Way Manual Chapter 6 – Right of Way Engineering
Reading Deed References and Acquisition History
The Record Map shows how each parcel was acquired. Recording information for Final Orders of Condemnation and related court documents is posted directly on the map, and Right of Way Engineering checks the legal description in the condemnation order against the original resolution before posting.2California Department of Transportation. Right of Way Manual Chapter 6 – Right of Way Engineering Parcels from earlier projects are cross-referenced between old and new Record Maps, so you can trace acquisition history across decades.
The map itself will not hand you the underlying deed or court order, but it gives you the suit number or recording data. With those, you can pull the actual document from the county clerk or county recorder.
Reading Survey Monuments
Record Maps show durable survey monuments that physically mark the highway boundary. Monuments are set at all angle points and at the beginning and end of curves along the R/W line, with supplemental monuments along tangent sections at intervals of no more than 1,000 feet to maintain line-of-sight between markers.8California Department of Transportation. Right of Way Survey Specifications Chapter 10 Monuments set in public highways sit at least 12 inches below the road surface, so you will not spot them by eye.
Caltrans also files separate monumentation maps, which are Records of Survey, with the county surveyor. Those become part of the public record and are useful alongside the Record Map when a surveyor is locating your boundary against the highway.
Excess Lands and Leases
Property the state acquired but does not need for the highway is classified as excess land. When Caltrans leases excess land, the lease boundary and the Director’s lease number appear on the Record Map.2California Department of Transportation. Right of Way Manual Chapter 6 – Right of Way Engineering If you are looking into whether a parcel next to a highway might be available for purchase or lease, the Record Map tells you whether Caltrans has already classified it as excess.
Getting a Certified Copy
A downloaded PDF is fine for research. Legal proceedings, property transactions, and some permit applications need a certified copy from Caltrans. Requests go to the Right of Way Engineering office in the district covering the highway segment, and your request should give the map number if you have it, or the route, county, and postmile range.1California Department of Transportation. Right of Way Maps and Survey Records
Fees for standard reproductions under the Public Records Act are limited to direct duplication costs.9California Legislative Information. California Government Code 6253 Certified copies cost more because the district has to formally attest that the copy matches the official record.
Check the Map Before Applying for an Encroachment Permit
Any work inside the state highway right of way requires an encroachment permit from Caltrans, whether the work is a utility line, a driveway approach, or a sign. The permit application requires construction plans that show the R/W lines.10California Department of Transportation. Encroachment Permits Manual That means you need the Record Map before you can finish the application.
Access control notations decide some applications before they are filed. If the map shows access denial along your frontage, a new driveway permit will be denied. Pulling the Record Map early saves the cost of applying for a permit that cannot be granted.
Working With Older Maps
California highway corridors have been surveyed and resurveyed over many decades. Older maps often reference the NAD 1927 datum while newer maps use NAD 1983, and the two are not interchangeable without a coordinate transformation. When Caltrans updates a corridor, previously acquired parcels are cross-referenced onto the new Record Map, but the older maps stay in the district archive and can carry details that did not migrate forward.
If your question involves an older acquisition, you may need both the current Record Map and the historical Appraisal Map from the original project. District Right of Way Engineering offices hold these files, and the staff there tend to be the most useful resource for a tangled acquisition history. For a straightforward boundary question, the current Record Map alone usually does the job.