Curb and Gutter Along Topo

Want to create a curb and gutter that actually follows your topo elevations? Tired of using complex slabs or sloped sweeps? Well here's an alternative way that creates a curb and gutter to follow the EXACT topography of your site plan! The only downside I have found to this method is that you need to be sure your topography is final (or darn close) and won't change at the areas of the curb and gutter - it can be a nightmare to change after the fact - you'll see why as you go through this tutorial.
Happy Curbing!

1. Create your toposurface as normal - making sure your elevations, etc are nailed down prior to moving on the the next step. :)

**TIP: I like to mock-up my roadways, etc with detail lines prior to splitting the surfaces, it gives me nice points to snap my sketch lines to when I am splitting surface later on**

1. Use the Split Surface tool to split the surface into 3 parts, forming your road - you'll have to do this twice as the Split Surface tool only allows you to split the surface into two parts each time.
2. On each side of the road, use the Split Surface tool again to split the surface into (2) 6" (or whatever your specs) pieces or slivers outward from each side of your road - this will later become the top of your curb and your gutter.
3. Go to an elevation view and move the road, and the two inside most 6" pieces (your gutters) down your required curb height.
4. Assign the appropriate materials to the roadway, curbs and topo (asphalt, concrete and grass) - now you can see things shaping up.
5. Now, using the Split Surface tool again, Split each of the four 6" spaces 1/8" from the their shared edge - creating (2) 1/8" slivers of curb in between each of the two 6" pieces.
6. Finally, go to a 3D view and use the Merge Surfaces tool and select the lower 1/8" curb piece and then the upper 1/8" curb piece - this will join the two 1/8" pieces to create your curb wall.

If you pick one of your topo pieces and try to edit them, you can see it doesn't bring you into sketch mode but into the actual Toposurface edit mode where you need to modify the elevation points in order to modify the surface. This is where it can get rather tricky and cumbersome if you need to modify your topo after you go through this process.