I wonder if people are referring to the buffer tool available with the LEHD “On The Map” tool. That is distance, but it is not travel distance.

Hello,

Both Kevin Tierney and Alex Karner are quite right about there not being a “distance” table in the ACS/CTPP files.

But now this brings up an interesting secondary question:  exactly how is this being calculated in the LEHD product?  Unless everyone who commutes to work drives their own car in a mostly uncongested and non-tolled environment, this is actually a lot more complicated to “get right” than one might think, even if a road network-based find-the-minimum-path approach is used.  I presume there is documentation about how the distance-based calculations are being done (surely it is something more than a straight-line between two centroids, multiplied by a national factor to represent circuity for auto travelers, but that would be my guess), but a quick search of LEHD and LODE documents did not reveal the answer.

Ken Cervenka

FTA Office of Planning