GIS or Unlicensed Surveying? The MySitePlan Case の座標変換

For decades, a turf war has simmered between Geographical Information Systems (GIS) professionals and Licensed Land Surveyors. GIS firms argue they provide accessible data visualization. Surveyors argue that drawing boundaries without a license puts the public in danger. In 2023, the State of California drew a hard line in the sand with the MySitePlan action.

中核的対立：製図 vs 測量

In the digital age, companies like MySitePlan emerged to fill a market gap: A homeowner needs a simple map to get a permit for a shed or fence. Hiring a licensed surveyor costs $2,000 to $4,000 and takes two months. A drafting company offers to pull county GIS parcel data, overlay it on satellite imagery, draw the shed, and deliver a PDF in 24 hours for $150.

The problem? Establishing where a property line exists on the earth is the exclusive legal domain of a licensed surveyor.

委員会の判決

The California Board found that regardless of massive disclaimers stamped on the maps stating "This is not a boundary survey," the fundamental act of depicting the relationship between a proposed physical structure (the shed) and a legal boundary line (the property edge) constitutes land surveying.

• The Board noted that county GIS data is notoriously inaccurate, sometimes shifted by 10 to 30 feet.
• When a homeowner uses a GIS drafting product to build a structure 5 feet from a property line, relying on defective county GIS data practically guarantees the structure will violate zoning setbacks or encroach on the neighbor.
• The company was ordered to cease offering services in California that depict property lines relative to physical features without a licensed surveyor's stamp.

地理空間業界への広範な影響

The MySitePlan enforcement action sent shockwaves through the GIS freelance community. It established a chilling precedent for anyone drawing lines on a map for profit.

What GIS Professionals Can No Longer Do (in stringent states):

• Draft plot plans for building permits showing setbacks.
• Create boundary maps for property sales (even if heavily disclaimed).
• Overlay CAD drawings of new infrastructure onto tax parcels for final location approval.

What GIS Professionals CAN Do:

• Create thematic maps (e.g., population density).
• Map environmental features (wetlands, forestry) for planning, provided they are not tied definitively to property boundaries.
• Provide broad visualization and planning graphics, provided they are not submitted to regulatory bodies for dimensional approval.

FAQ

See also: GIS Legal Evidence | Standard of Care | Survey Dispute Cases