concrete coating river crossing

[allmerrick]

Hello,

We need to conctrete coat an 8" line for a river crossing. I need to know how long I have to keep the coating along the risers, if the codes says something about this.

We achieve the buoyancy with the flat section but I need to know if I have to also coat the risers because of the code...

Thanks for any help!

 

[cvg]

what code?
8" pipe? what kind of pipe?
risers?
what kind of "crossing"?
how, what and why are you "coating" something?