Traps on surface water drains - Traps on surface water drains

[Scaifee]

Hi

I am currently designing an extension toa factory. I am adding an new portal frame building with eaves gutters & downpipes. Building control are asking me to trap the outlets at ground level where my intention was just to simply connect to the below groud system and pat access covers just above ground level on the RWP's. The drainage system is separate.

Anyone have any idea why traps are requested?

Cheers

Scaifee

[lutonlagerlout]

because otherwise, leaves and deitrius go down the pipe and block it up in a matter of years
its a new one but we have been doing it for 6 months now on all surface water .
pipe will never block if you think about it
cheers LLL