Septic tank

[Ktelobb]

Hi, we are just about to start our new build property having just demolished the existing house. Would like some advice on septic tanks. We are not on mains sewers and there is an existing very old concrete Septic tank. What would be the best replacement for it on a clay soil site.  It’s going to be a large 5 bed 6 toilet house. Thanks 

[scottishjohn]

depending where you are 

here in scotland you will have to have a treatment plant now .not a septic tank ,but maybe they will accept the old tank -- planning will be the only ones to decide that 

 you must having planning --so what does it say on the PP and your plans ?

your answer is there 

[ProDave]

Actually the decision is split between planning and building control.  It's possible to get planning for one scheme and then building control refuse it and you end up with something else.  ask me how I know.

 

Your issue is going to be your clay soil and the percolation rate for the drainage field.  you need to do some percolation tests very soon before you can plan anything like where and how big the drainage field needs to be.  Add in the building control limits that say how far is must be from a building, boundary etc and it can end up needing a lot of space.

 

Id there a watercourse available to use?  That saves a LOT of problems and is what we ended up using (though harder to get permission for in Scotland)

[Temp]

In England I think the output of a septic tank can go to a drainage field but id still probably want a treatment plant if it was me.

 

+1 to doing the percolation test asap as you cant make any decisions until you know whats feasible.

 

Soakaways don't work on our plot so were fortunate to be allowed to discharge rainwater into a piped ditch along the road boundary. If the EA had refused that im not sure what options were left. 

[SuperJohnG]

3 hours ago, Ktelobb said:

Hi, we are just about to start our new build property having just demolished the existing house. Would like some advice on septic tanks. We are not on mains sewers and there is an existing very old concrete Septic tank. What would be the best replacement for it on a clay soil site.  It’s going to be a large 5 bed 6 toilet house. Thanks 

Question being why do you want to replace it?. If you have an existing approval you can currently stick with this and leave it alone.. If you need to move it then you can think of doing a sewage treatment plant as it is much better effluent discharge. If you have clay soil as above you can do a percolation test (regardless of soil type). 

 

I did my SI last week. I had however already applied for a new discharge into a burn that runs through my site...but my justification for discharging into the burn on the application was because the burn was close. Apparently thats not good cause from SEPA. Anyhow....done SI and we have clay and high water table...ill be discharging into burn. 

 

I was glad as I didnt want a soakaway,.pointless when I have a burn and I'm buying a sewage treatment plant.