Question
I am having a problem on drawing finish contours for a access road. How do I know where they catch at the existing contours?
Thanks
Jerry

Answer
If you are creating a grading plan, your first bit of information should be a topographic map of the existing condition.  With that, your proposed design is placed on top of this map will show you how close or far your design is from the original condition...Then just match up the numbers - 95 to 95, 98 to 98, etc.

Hopefully not TOO far off at the edges of your design, as the farther "off" they are, you'll have to make them fit together by using slopes (no greater than 2:1)or walls to bring it all back the "ground", where they meet up with the rest of the world.  If the road is above the original grade by several feet, your design may even be creating "new" contours floating above the original topgraphy - kind of like that children's game of concentric "rings" that you stack on a pin.

And the general rule is you cannot cross property lines doing this!   The Uniform Building Code says you cannot even get within 2 feet of a property-line to do this.

Add to that, with a road, you may have had to add a curb & gutter or shoulder swale...and where these meet existing slopes or gulleys, the contours get distorted.  

Here is an extreme example:  

http://www.flickr.com/photos/1sock/354092948/

I poked around on the internet quickly to see if there was a simple graphic on how to do this, but couldn't find one - sorry.  There is a lot out there for landform manipulation using CAD programs, but none for hand-drafted versions...I think it is a dying art, with CAD-assisted draped surface modeling and all that out there.  

I am also assuming you meant grading in hand-drawn format, as opposed to some CAD pack with surface TINs and the like.

For handdrawn versions, two good sources of information are the Time-Saver Standards for Landscape Architecture (McGraw/Hill), and Site Engineering for Landscape Architects (AVI Publishing).  I'm sure there are more.

One last bit of information: for drainage elements with "points" like a gutters or swales, remember that the "point" always point uphill.  Berms and roadway crowns point downhill!  Simple, but a common mistake.

Hope it helps ~M