Specify ditch coordinates with station and offset?

[CyberAngel]

We often have ditches in roadway cross sections. I create a feature line to model the bottom of the ditch, so that there's a target for the slope into the ditch. My question is, is there any way to specify a point by providing a station and an offset off the road alignment, so that I can place the feature line nodes accurately? What I've been doing is 1) draw a series of circles centered on where the sample lines cross the centerline; 2) draw the feature line with each vertex at the intersection of a circle and a sample line; 3) provide the elevation based on the elevation needed in the cross section. Yes, it would be more efficient to draw one long segment and let AutoCAD extrapolate the elevations, but our ditches never line up that neatly.

 

A better question might be, is there a more efficient way to create a ditch in cross sections? Up until now, we've been doing all this by hand. Judging by the lack of discussion on this particular item, it's so easy nobody has problems, or they're doing it manually too.

[BIGAL]

This was asked recently for a different civil package running under Acad etc, you can make services and these are detected in the long and cross section. I can point you in right direction but not a free answer.