Building a cesspit

Hi,

I'm after some ideas / advice really.

I'm building a new cesspit. All we are alowed here are catchment pits, no treatment or discahrge etc at all by law. We have a semi above ground concrete pit in poor condition at the moment. I want it completely underground.

I've dug a big hole in the garden in the new location. I was looking to purchase a ready made plastic tank and pour concrete around it, but it would appear to be very expensive as I'd have to import one.

I've gone back to the original idea of building a re-enforced concrete pit with wooden forms, then getting the concrete mixer around to fill them up.

A couple concerns I have.

Thick ness of the walls? I was thinking 4 in, with some rebar
Water in the hole! It's about 8x7x6, and it fills up with water in a week with all this rain. I'm currently pumping it out, but once the concrete is in there, will I have to keep it pumped out for a few days, or can you just let the water back in?
Water table - Very high in winter, as can be seen by my full hole. Will my pit pop out of the ground?

Finished pit size would be about 6x6x6

Whats the normal method for building these? I can find very little info on the web at all with regards to cesspit construction.

Thanks.

General practice is to dig the hole and drop in a preformed fibre glass or polyethylene cess pit then backfill, BCO will probably prefer this as well. You will need a minimum of 18,000 lts capacity to comply with Building regs - twice what you propose.

Jason

Hi, thanks.

I'm not on mainland UK, and there is no actual minimum capacity . 1000Gals is quoted as normal and is the current recommended min size