Converting 3D line drawings to 2D in plan view

[Jayatissa]

I got a site plan covering larger extent of land prepared by a Surveyor. The plan consists of contours and roads marked. Though it looks like a flat (2D) drawing, from the plan view all the coordinates has (Z) value. Because the plan drawing is derived from a 3D contour plan created by another software used by Surveyor to AutoCAD.

My exercise is to prepare (2D) plan drawings of buildings to be erected on site. After drawing individual building plans I found it difficult to place them on the site plan as it has lines with 3D coordinates. If I could bring all these (z) values to (0) value, I can utilize the same site plan to place my new objects. My requirement is only to place my drawings on a plan view and I do not want 3D lines of the site any more. I appreciate if you could guide me to over come this problem. Thank you.
Jayatissa - Sri Lanka

[tedg]

I got a site plan covering larger extent of land prepared by a Surveyor. The plan consists of contours and roads marked. Though it looks like a flat (2D) drawing, from the plan view all the coordinates has (Z) value. Because the plan drawing is derived from a 3D contour plan created by another software used by Surveyor to AutoCAD.

My exercise is to prepare (2D) plan drawings of buildings to be erected on site. After drawing individual building plans I found it difficult to place them on the site plan as it has lines with 3D coordinates. If I could bring all these (z) values to (0) value, I can utilize the same site plan to place my new objects. My requirement is only to place my drawings on a plan view and I do not want 3D lines of the site any more. I appreciate if you could guide me to over come this problem. Thank you.
Jayatissa - Sri Lanka
Congratulatons on your first post!
Have you looked into the "flatten" command?

[irneb]

Or even selecting all and open Properties Palette. Then change lines start and end point Z values from *varies* to 0.0. If they're polylines, change their elevation to 0.0.

Flatten could cause some problems with text and blocks, so be careful.

If you don't mind having lines in 3d, but you want your own drawing to be on a 2d plane. Open the Options Dialog (Tools --> Options), then on the Drafting page check "Replace Z value with current elevation" in the lower left.