As a follow-up to the post Feature Line Styles Control What?:
‘Featureline Priority’ is most likely a feature – no pun intended – in Civil 3D that you have overlooked or didn’t even know about. As you do know, if Featurelines are in the same ‘Site’ they interact with each other and the last one edited wins.
For example:
If you have two Featurelines that cross each other and are in the same ‘Site’, Civil 3D will force them to be at the same elevation where they cross. This is a good thing since they need to be to build an accurate surface (review image below).
Again, when NOT using Featureline Priority the last one that is created or edited generally WINS and will adjust the other. But with Featureline Priorities you can prioritize the Featurelines by style and use that to control which one will win/adjust.
In the past year I didn’t see a big benefit to using Featureline Priorities until a situation came up a couple of months ago that opened my eyes. Lets review this common scenario and see how Featureline Priorities saved the day.
First, lets review how Featureline Priority works. It is simple really, it is based on the Featureline Styles. Generally, I recommend to NOT assign styles to Featurelines, BUT in this case we will make an exception.
To see the priority list, right-click on "Feature Lines" under the ’site’ that contains your Featurelines and click "Properties…".
Next, proceed to the "Options" tab. There you will see all the Featureline styles that are in the drawing and their order of priority. Adjust them accordingly…
So basically, if I now assign the "HRG_Building" style to what was the BROWN line and the "HRG_Curb" style to what was the MAGENTA line, no matter how much I edit the curb featureline it will NOT adjust my building featureline. Make sense?
So where does this come in handy; handy enough to out weigh the added complexity? It comes in handy for residential projects; between the road and the house pads. Typically, you would build the road with a Corridor Model and the house pads with Featurelines. In between you have Featurelines that represent the driveway edges and adjust if the road or house is moved up or down.
Lets look at how this scenario works without using Featureline Priority and then also with using Featureline Priority:
2010.02.01-Featureline Priority-FINAL
BIG DIFFERENCE … !!
Thanks and I hope this helps prioritize your grading tasks! 
Wow very very interesting. I will definitely have to check this out.
I know, for me it just takes one practical use to make me stand-up and take notice. This was the exact issue a user was having before we used Featureline Priorities. We tried to implement to see if it would help and BAM! Seeing how much better things reacted with Featureline Priorities enacted was all the convincing I needed to start using it.
Figured that was worth sharing.
I just revised the video to a WMV file instead of YouTube. Just figured out how to do that – I know it’s sad – and I know a lot of folks can’t access YouTube at work. Including myself…
Thanks for the tip. This will come in handy for the work we do. Also a big thanks for the non Youtube posting. We’re one of those Youtube blocked at work.
Tell your IT guys to get out of the dark ages. While there’s a lot of crap on YouTube, there’s a TON of free training material they’re depriving you of.
Great tip. SInce the terrain I work in is existing roadways, very flat and feature dense. I spend a lot of time getting existing ground a perfect as possible. Typically I am grading road at 0.3% profiles and even flatter. Working to save existing driveways, curbs and sidewalks can cut a project’s cost in half. Before Civil3d I used a number of tricks to input cross sections and densify breaklines. Feature lines are the single best feature in Civil3d. I typcially add them for centerline, shoulder, gutter line, top of curb and back of sidewalk. I create my existing grade surface almost exclusively by added feature lines and supplementing them to ten feet and .2 middle ordinate. Intersections are handled by running the gutterline back the side street and over the crown to seen whether they are draining towards me or away.
Thanks for the time you spend sharing these tips. Kent
No problem. I’m glade it helps!