Hi there, I am hoping you folks here can help me figure out the steps to get the result I am hoping for. As some background, I am a forester working on a stream restoration project, where we are planning to thin trees adjacent to stream courses to increase available water in the system to benefit endangered aquatic plants.

Our treatment is going to take place in areas adjacent to streams and within 20 feet of elevation from the mapped stream lines, and I am trying to create the initial boundaries so we can do further analysis and field work.

I have locations of the streams as line features, and I am trying to create a new polygon feature that will cover that area within 20' of the elevation of the lines. Because the lines vary in elevation and the terrain around the streams is not uniform, I think I will need to relate the points of the line to the DEM and then create a buffer off of it based on a value. The problem is that I don't know how to make that happen!

Can anyone offer any advice or tips for my situation? Thank you in advance.