Grade to surface with a negative slope only?

[mikeosborne]

I have a corridor and I need to grade from a point at -2% to a surface. But I need it to only grade at -2% to the surface. When the point is in a cut position I do not want the point to grade up to the surface I want it to keep grading at -2% and daylight at the surface. Any ideas?

[cadtag]

If I understand this, the point is _below_ the surface (eg cut condition), and you want to grade _down_ to daylight at a surface that's above??????

without creating a swale it would seem to be geometrically impossible.

[davila.vanegas]

ok if i understand, you need to get a grade with -2% and a define distance? If this is the situation in cut condition you should change your subemsambly.