Right-of-Way Parcels

Right–of-way, or ROW parcels, track land that is typically used for movement, transportation, or utilities.

Our ROW implementation, in the ll_row_parcel field, identifies ROW parcels by a variety of methods and is available in our premium dataset. We expect to iterate on this first implementation over time.

Rights-of-way are helpful to have identified for multiple reasons:

  • ROWs typically do not have an address or buildings associated with them. Excluding them from analyses where this is important can improve quality.
  • For some use cases, like utilities, knowing rights-of-ways is important, so we do not typically remove them from our dataset.
  • Large, twisty "spiderweb" ROWs with many vertices can cause problems with geoprocessing. These typically represent a large network of roads. In cases where we identify processing problems, we remove them from our dataset

Example ROW parcels

Example ROWs following a highway in Frederick, MD:

Example ROWs following a highway in Frederick, MD

Spiderweb ROW in Abbeville, SC:

Spiderweb ROW in Abbeville, SC

ll_row_parcel attribute values

We combine a number of heuristics to determine if a parcel is a ROW. The criteria used for the determination is stored in the ll_row_parcel field. Each of these criteria is also combined with logic to identify public and homeowner's association-type owners to minimize false positives:

Value Definition
parcel_number parcelnumb contains "row", "road", or other relevant identifiers
land_use usedesc contains "row", "road", etc.
perimeter_ratio The ratio of the parcel's perimeter to its area suggest this parcel is part of a street network or other "spiderweb"
hull_ratio The ratio of the parcel's area to the area of a convex hull drawn around the parcel suggest this parcel is part of a street network
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