[Taxacom] odometer georeferencing

[Kenelm Philip]

Doug Yanega remarked: "Highway markers should also, in theory, be quite
stable once georeferenced, where the edge of a town is a subjective
quantity,
and subject to *wide* interpretation -"

This does not hold in northern regions. On the Dempster Highway, in the
Yukon Territory, some of the kilometer posts were moved between 1987
and 1989. The Dempster Highway section along the west foot of the
Richardson Mountains somehow lost 4 km in a 50 km section! Yet
there had been no highway realignment in that section... On the Parks
Highway, in Alaska, the mileposts were not moved, but the road was
realigned, so that in some cases it is now 0.6 miles between mileposts,
which means that odometer readings now diverge from milepost readings.

In either case, milepost or odometer readings should be dated on any
highways subject to realignment, and it appears that milepost readings
can change even when the relevant road section has not been realigned.

                  Ken Philip