Milepost equation

A milepost equation, milepoint equation, or postmile equation is a place where mileposts on a linear feature, such as a highway or rail line, fail to increase normally, usually due to realignment or changes in planned alignment.^[1][2] In order to make mileposts consistent with the real mileage, every milepost beyond the equation would need to be moved.^[3]

For example, an equation of 7.6 back = 9.2 ahead means that the feature does not have any section between mile 7.6 and mile 9.2, and the distance between mileposts 7 and 10 is only 1.4 miles. This would usually be caused by a relocation that shortened the distance by 1.6 miles. It is also possible for an equation to add mileage to what it would otherwise be; the duplicated mileposts receive a special prefix, such as Z.^[1]

See also

• California postmile

References

1. "ODOT Approved Terms & Definitions". Oregon Department of Transportation. Archived from the original on June 24, 2007. Retrieved August 7, 2020.
2. "STB Docket No. AB-33 (Sub-No. 220X)". Federal Register. 69 (190). October 1, 2004. Archived from the original on August 7, 2020. Retrieved August 7, 2020.
3. "UDOT Milepost Project: Project Plan". Utah Department of Transportation. Archived from the original on August 7, 2007. Retrieved August 7, 2020.