When working with station equations on an alignment, it is possible to reverse the direction of stationing on the alignment.
To achieve this, you will need to identify the location of the change in direction. In the example below I have used the station 205+00. If an actual equation does not exist at the change of direction then the user should use the changing station as both the BK and AH stations.
After you have identified the start of the change in direction you must then identify the end of the change, either the end of the alignment or an intermediate station. In the example below, we are using an intermediate station of 201+00 so that you can see the change in the screenshot.
In the example above you will see that the stationing is increasing from left to right until it reaches the our first equation at 205+00. Then the stationing begins to decrease from left to right until it hits the second equation at station 201+00, and then begins to increase in stationing again.