Linear Reference System

The Linear Reference System (LRS, also called Linear Referencing System) is a reference system in which features are localised by a measure along a linear element. Each feature is localised by either a point known as a "milepoint" or a linear event ("segment"). The system is designed so that if a segment of a route is changed only those milepoints on the changed segment need to be updated. Linear referencing has the capability of locating attributes along a line with only one parameter as opposed to two (e.g. latitude/longitude).

The LRS is suitable for management of data related to linear features like roads, railways, oil & gas transmission pipelines, power & data transmission lines and rivers.

A system for identifying the location of pipeline features and characteristics by measuring distance from the start of the pipeline. An example linear reference address is: Engineering Station 1145+86 on pipeline Alpha = 114,586 feet from the start of the pipeline. With a Reroute Cumulative Stationing might not be the same as engineering stationing, because of the addition of the extra pipeline. LRS solves this dilemma, and the appropriate measures. LRS is supported for example by GRASS Geographic Information System and PostGIS.