I came across a survey of the state highway that goes by a parcel of land upon which I'm developing my control network (educational endeavour). It was done in the 50's when the highway was re-routed. I added several of the old points noted on the survey to my map(and have found some of them on the ground.) I was curious to find where the highway used to go (through the property actually).
But during the course of things I COGO'd from a point I'd set to a point from the old survey and was surprised that it showed a horizontal distance of say .15' and a vertical distance of nearly 1000', which of course makes sense because I just drew the map without entering any elevation data.
But it raises the question of how one adds such information to a drawing--especially if there is incomplete elevation data available. Do you just draw it at "sea level", i.e. everything at 0'? Add what points you do have information for? Many old surveys I've seen have NO elevation data...just metes and bounds. Do you just put such stuff on another layer and not even worry about it? Just curious how this is routinely done.
Boundary is treated as 2D, no elevations necessary