Highway location reference methods.

This primary objective of any highway location reference method is to provide a means for designating and recording the geographic positions of specific locations on a highway and for using the designations as a key to stored information about the locations. The most significant characteristic of any method is its orientation toward use in field. There must also be a uniformity in the procedures through which locations are indentified and recorded to facilitate correlation of all points. Three elements common to all location reference methods are (a) identification of a known point, (b) a measurement from the known point, and (c) a direction grouped into two categories-sign-oriented methods and document-oriented methods.