I need to model two cul-de-sacs. I have seen workflows for modeling a normal crown cul-de-sac where the pavement slopes outward from the center point of the cul-de-sac. However, in order to facilitate drainage efficiently, I would like to model a special cul-de-sac. See white flow arrows in the first screenshot below.

I thought I had a good workflow in my head. I created a Top alignment and profile and set the elevations I wanted (see highlighted alignment in screenshot.) Then created a Bottom alignment and profile (remainder of the orange cul-de-sac not highlighted). My thought was to project the top profile down 2% to the bottom profile. So I used the profile by slope from element tool to accomplish this. However, the profile did not turn out as I had planned. I am not sure how I can have the pavement slope at the angle I have my flow arrows at. Additionally, even if I get both of these profiles at the proper elevations, which alignment would the cul-de-sac corridor be modeled from and what would that template look like? If anyone has any suggestions, I would love to hear them! Thanks!