topic Re: Intersection elevation target mapping in Civil 3D Forum

Intersection elevation target mapping

chrispooley0 — Mon, 01 Jun 2026 02:35:10 GMT

Hi All,

I have an intersection, I am trying to get the elevations correct, and I cant seem to figure it out.

I have created a feature line with the correct elevations that I want the top of the kerb return fillet to connect to, and I want the inside edge of the road to have the same elevation as the horizontal connection. however it is sticking up very high.

Please see the images so you can see what I am talking about.

As I read my question, I am confusing myself, I am not even sure what to ask help with.....

The horizontal connections are correct for this intersection, however the inside edge and outside edge are both very high. I dont know how to bring them down. I have created the pink feature line, that would be the correct height for the back of kerb, however when I set this as the elevation target, only the inside of the kerb return fillet comes down. The below image is the cross section view of the area im in. The side on the right is the main road, and the side on the left is the intersection (or kerb return fillet) coming into it. I need the inside to come down a little bit to connect to the main road, and I need the outside edge to drop down so I have a 2% grade from the kerb to the center of the road:-

I hope this question makes sense...

Thank you,

Re: Intersection elevation target mapping

VincentSheehan — Mon, 01 Jun 2026 12:04:38 GMT

Is the profile the radial return? Set a new profile and have the Kurb target that profile.

Re: Intersection elevation target mapping

chrispooley0 — Tue, 02 Jun 2026 01:21:55 GMT

Hi Vincent Thank you for persevering with that horrible question.

I am not sure what a radial return is sorry. I have 2 profiles in the area, number 1 in the picture below is the main road, the levels and the level of that profile is correct. Number 2 in the image below is the intersection. The profile is correct, but the kerb levels, or the outside edges are too high.

In the image below, I am hoping to bring the outside edge (where I have drawn the blue line) down to the level of the pink feature line that I have shown with the red arrows.

I thought I would be able to set the elevation to that feature line using the target mapping, however, there is no way to set the back of the kerb to target the feature line separately from the inside (or middle of the road). If I target that feature line, only the middle of the road drops down, the back of kerb does not change.

I think I have made what I am asking for help with a little more clear now.

Hopefully this is a sensible question now.

Thank you,

Re: Intersection elevation target mapping

Joe-Bouza — Tue, 02 Jun 2026 11:06:58 GMT

I agree, it’s tough to follow. AFAIK, The top of curb for OOTB sub does not have a vertical target.

I had success building a curb from generic links to control to top of curb

Re: Intersection elevation target mapping

rosie_lucas1 — Fri, 05 Jun 2026 15:53:39 GMT

Hi @chrispooley0,

Just following up - were you able to resolve the issue, or do you still need help?

If you’ve found a solution, we’d love if you could share it here so others can benefit. If not, feel free to post an update anytime.

Best regards,

Re: Intersection elevation target mapping

dkennedy — Fri, 05 Jun 2026 20:46:58 GMT

Maybe instead of using a feature line, Try offset alignments, coupled with connected alignments?

Re: Intersection elevation target mapping

chrispooley0 — Mon, 08 Jun 2026 22:34:52 GMT

Hi @dkennedy , Thanks for the suggestion, I will give it a go.

Re: Intersection elevation target mapping

chrispooley0 — Mon, 08 Jun 2026 22:37:18 GMT

Hi @rosie_lucas1 , Thanks for following up. Sorry I went quiet for a couple of days, we had a very long weekend here in Australia for the Kings Birthday. I will try @dkennedy suggestion with the Offset Alignments, I have not used these before, so I will take some time to teach myself what these are and how to use them.

Thanks again,