Pit Dimensions

[Maxi Eng]

Hello fellow engineers,

I was wondering if anyone could shed some light on minimum stormwater pit dimensions for certain outlet depths as per Australian Standard AS3500 (screenshot below).

For example, why is a 450x450 pit limited to an outlet depth of 600mm? What are the consequences of exceeding this depth?

Thankyou in advance!

 

[HTURKAK]

For example, why is a 450x450 pit limited to an outlet depth of 600mm? What are the consequences of exceeding this depth?

If the invert level of the outlet is LT 600mm, cleaning and maintenance can be made with insertion of a hand (as for lifting) or of a hand and arm . These could be called handhole also , which is a type of small manhole, too small for access but useful for inspection and washing out the mechanism.

If the invert level of the outlet GT 1200mm, acess could be necessary for inspection and maintenance , so could be called MANHOLE .