Any tips on self installing a sewage treatment plant

[pugwash4x4]

Need to change our old sceptic tank for a new wastewater treatment plant.

The old location is unusable and so the new system will be located towards the front of the house.

It seems that anyone we invite to quote doesn't seem to know what they are doing or is insanely expensive. We are getting quotes for 25k plus vat for a 6pe marsh tank and 18m of pipe in trench with 3 man holes.

It's not something I've done before, bit I can't face spending 25k on something that isn't particularly skilled and so I'm considering doing it myself.

Has anyone else self installed, was it particularly hard? Any tips you can offer?

 

[coopersim]

We did our own after the same experience you’re describing.

we invited the klargester rep around for advice who suggested the location and model of unit, we applied for building regs ourselves, hired a digger, arranged concrete and laid all our own ducts and pipes as per the manufacturer guidelines.

it was hard work and we’d under specified the digger size so had to upgrade part way through the job (get a three tonne minimum!)

it did save a lot of money though and worked perfectly afterwards.

 

[pugwash4x4]

Thanks Cooper- great idea on asking the rep round- thank you

 

[Hugh Jaleak]

Check and double check your levels, sh1t wont flow uphill, you'll need a minimum 1:100 fall to the tank from the invert level where you pick the existing drain up from. Any excavation over 1.4m deep needs supporting, and make sure there's nothing buried before you start digging, break a gas pipe or electric cable and there's easily a several £K bill for repairs, damage a BT cable, then think of a number and double it. Fibre Optic repairs can go into 6 figures.

Afraid the above pic is a classic example of what not to do, never dig or lift cross tracks, it is the easiest way to tip a machine over!

Tank will need anchoring into the ground, usual practice is to site it on a concrete base, may need surrounding with concrete, as they've been known to pop up like a sponge out of water, in areas with a high water table after being emptied! Drainage, all will need bedding and protecting with peagravel, any shallow pipework may need haunching over with concrete for protection. Comply with manufacturers instruction at all times or you could void any warranty claim.

 

[pugwash4x4]

Thanks Hugh really appreciate your reply.

Services aren't an issue as they either run overhead OR they run in channels I dug.

The bit I'm trying to resolve is how to create manholes!

 

[Hugh Jaleak]

Which part of creating manholes are you struggling with? Much as I dont like them, the preformed plastic chambers seem to be the industry standard now. Provided your drains are not too deep, they should suffice.

 

[lostinthelight]

The bit I'm trying to resolve is how to create manholes!

I used this sort of thing.
"600 x 450 x 150mm HIC Concrete Chamber Section - JDP" https://store.jdpipes.co.uk/600x450...kqtUxLj0yh_VTFcDF3BjdfpkqfPKBxyMaAj_hEALw_wcB