How Land Surveyors Mark Property Lines: Understanding Deeds, Plats, and Public Records
Determining exactly where one piece of land ends and another begins is a foundational part of property ownership. Whether you’re preparing for construction, resolving a boundary dispute, or simply learning more about your land, understanding how surveyors establish property lines can be incredibly valuable. This post walks through how licensed land surveyors use deeds, plats, and public records to perform boundary surveys and physically mark property lines.
1. Starting With the Property Deed
The process typically begins with the property deed, which is the primary legal document describing who owns the land and the boundaries of that ownership. Deeds contain a written description known as a legal description. This may appear in several formats:
- Metes and bounds — describes boundaries using distances, angles, and landmarks
- Lot and block — references subdivision lots recorded on a plat
- Rectangular (Public Land Survey System) — uses township, range, and section numbers
Surveyors analyze the deed to understand the original intent of the property boundaries and to identify any ambiguous or conflicting language. If multiple deeds reference the same boundary, surveyors must interpret the hierarchy of evidence based on longstanding surveying principles.
2. Reviewing Recorded Plats and Maps
Next, surveyors look at recorded plats, which are official maps filed with the county recorder or land records office. These plats show:
- Lot dimensions
- Subdivision layouts
- Road rights-of-way
- Easements
- Reference monuments used for measurements
A plat is particularly important in modern subdivisions where lots were designed and recorded all at once. Surveyors compare the dimensions on the plat to those in the deed to ensure consistency and identify any discrepancies.
3. Searching Public Records for Historical Evidence
Boundary determination often requires more than a single deed or plat. Surveyors typically perform a detailed search through public records, including:
- Past deeds and conveyances
- Older surveys
- Adjoining property descriptions
- Probate records
- Court decisions
- Road or utility right-of-way documents
Historical evidence can reveal how boundaries changed over time or clarify unclear calls in a deed (such as references to trees, stones, or fences that no longer exist). This record research helps establish intent—often the most critical factor in determining true boundaries.
4. Field Investigation and Locating Physical Evidence
With the documentary research complete, the surveyor heads into the field. The goal is to locate both existing monuments (physical boundary markers) and natural or artificial features that match the descriptions in the deed or plat.
Monuments may include:
- Iron rods or pipes
- Stones
- Concrete markers
- Wood stakes
- Old fences
- Walls or hedgerows
Under boundary law principles, monuments generally take precedence over measurements. If a deed says “to the iron pin,” and the pin is found in a reasonable location, it usually governs—even if the distances differ slightly from the written description.
5. Calculations, Boundary Resolution, and Marking Lines
Using collected field data, the surveyor performs detailed calculations to reconcile measurements with record documents. If inconsistencies arise (which is common), the surveyor applies established legal and professional standards to resolve the boundary.
Once the final boundary determination is complete, the surveyor marks the property lines by:
- Setting new iron pins or monuments where needed
- Flagging the line for visibility
- Preparing a survey map (plat of survey)
- Filing or recording the survey, where required by state law
The resulting survey provides a defensible, professional determination of the property boundaries and reflects the surveyor’s expert judgment based on documentary, physical, and measured evidence.
6. Documentation Delivered to the Property Owner
The surveyor typically delivers:
- A survey plat/map
- A written report or notes
- Coordinates and measurements
- A description of found and set monuments
- Any identified encroachments or conflicts
This documentation becomes part of the property’s record and can be valuable in future transactions or improvements.
Conclusion
Land surveying is a careful blend of legal interpretation, historical research, measurement science, and field investigation. Through deeds, plats, and public records, surveyors piece together the story of a property’s boundaries—and then translate that story into precise, physical markers on the ground.
Footnotes / Credits
- American Congress on Surveying and Mapping (ACSM). Principles of Boundary Law and Land Records. https://www.nsps.us.com
- National Society of Professional Surveyors (NSPS). Boundary Surveying Standards and Best Practices. https://www.nsps.us.com
- Bureau of Land Management (BLM). Manual of Surveying Instructions. https://www.blm.gov
- National Geodetic Survey (NGS). Surveying and Geospatial Data Resources. https://www.ngs.noaa.gov