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jeffbo01
19th February 2008, 01:58 PM
Hi there
We bought a house recently on the low side of the street and with the heavy rain recently have discovered that (with CCTV and eels) our current absorption pit is clogged and not up to the job.

So we need to redirect the stormwater to a new pit. We can't dig up the existing one and redo as its under a concrete driveway.

We had a plumber quote on doing the whole job and it was really expensive so we decided to do the digging and hardwork ourselves and get the plumber to do the connecting of pipes.

So can someone tell me the specs for a decent size pit (ie how deep, wide it should be if 3m long). Also any useful instructions about materials to use to line the pit.

journeyman Mick
19th February 2008, 07:19 PM
The size of your pit would depend on the catchment area it services, your expected highest intensity rainfall and the speed at which you can remove water from the pit.

Mick

wonderplumb
19th February 2008, 07:49 PM
Mick has summed it up pretty well, square area of roof, paved areas serviced by surface drains, it will also govern how deep you go and how much square area around the absorbtion trench you need, which will give you cubic metres of drainage material ( blue metal etc.) you need to drain storm water away from your house.

Have a look at AS3500.3.2 1998

or Im sure the HB39 (national roof plumbing and wall cladding code) may give you some answers.....

Enjoy!

PS, check with local council, who is usually the authority that governs storm water.