Distance Accumulation attributes

HeatherFox1

I have created a distance accumulation raster using a road layer, and I'm wondering if there is a way to attribute the raster with the road information that it is measuring the distance from. The goal is to know how far a location is from a road, but I would like to know what type of road it is. Is this possible? Or is there an alternative way to go about it?

Robert_LeClair

Yes—use Distance Allocation (instead of only Distance Accumulation) so you get both:

• a distance raster (how far to the nearest/least-cost road), and
• an allocation raster that stores which source each cell is assigned to.

Try these steps:

1. Run Distance Allocation with your roads as the Input raster or feature source data.
2. Set Source field to a road attribute you want carried through (for example ROAD_TYPE), or better, a unique key like ROAD_ID.  This must be an integer field though.  So perhaps you calculate a ROAD_TYPE field of 1 for interstate, 2 for US Highway, 3 for State Highway and so on.
3. Use the outputs:
   • Output Distance Accumulation Raster = distance to the closest/least-cost road.
   • Output Distance Allocation Raster = the value of your Source field for the road that each cell is allocated to.