Calibrating routes assigns measure values to route features from an external source, so they can be use to find and display route events. New routes that do not have measure values must be calibrated before they can be used. You can also calibrate routes that do have measure values to improve the accuracy of the measures, if you have a source of measured location data that is of better quality.

Imagine that at some point after the routes were created, the highway authority’s road maintenance crew acquired a distance measuring instrument (DMI) to accurately record mileage information along the highways. For a sample set of highways, the crew went out and captured mileage information approximately every 1/10 of a mile. The results of this effort were stored as points in a shapefile, where the route and mileage information was stored as attributes.

In this segment you will see how to use the Calibrate Routes tool to adjust the measures of the routes to match those of the points in the shapefile. The result will be written to a new feature class.

The Calibrate Routes tool lets you specify a route feature class, the route identifier field, the input point feature class containing the calibration data, the measure field in the point feature class, the methods used to set the route measures, and the new output feature class that will contain the calibrated routes.

A tolerance can be specified to limit how far a calibration point can be from its route. Points outside the tolerance will not be used by the calibration process.