A Warrington property came to us with two septic tanks, surface water and foul waste going into the same system, and everything discharging into a field soakaway. That setup doesn’t meet Environment Agency binding rules. Here’s how we sorted it, and the problem we hit on site.
The problem
The owners contacted us about their foul waste system. When we got there, we found:
Two septic tanks serving the property
Surface water and foul waste combined in the same drainage
Discharge into a field soakaway system
That adds up to a non-compliant system. Rainwater shouldn’t be going through a foul system, and the discharge didn’t meet the General Binding Rules.
Survey first, then a clear quote
We carried out a full drainage survey so we knew what was actually in the ground before recommending anything. We then sent a compliance quotation, which the owners accepted. The install was booked for the week commencing 19th October 2026.
What we installed
Drainage separated. Foul and surface water are now on separate runs.
Marsh Ensign PE008IPS sewage treatment plant installed, taking all foul drainage from the property and discharging into the existing outfall.
Surface water redirected into soakaways, sized on the roof area they serve.
Both old septic tanks decommissioned.
The complication: running sand
The ground had running sand. That’s sand that flows into the excavation as you dig, so the sides collapse and water keeps coming in. It can make a straightforward install very awkward.
We changed our install procedure for the job. We used shuttering to hold the excavation and dewatered it so the tank could be set properly. It slowed things down, but it’s the right way to deal with ground like this. Cutting corners here risks a tank that settles or shifts later.
Sign-off
Warrington Council building control approved the installation
Electrical Part P certification completed for the plant’s electrical supply
All excavations backfilled and the area left clean and tidy
The site’s foul water system now complies with Environment Agency binding rules
Advice if you’ve got a similar setup
If your surface water and foul waste share a system, it’s worth getting it looked at. It’s a common problem on older rural properties.
Don’t assume a soakaway is fine because it’s always worked. A drainage survey tells you what you’ve actually got.
Ground conditions can change the job. Ask your installer how they’d deal with a high water table or unstable ground before you agree a price.
Need a drainage survey or compliance work? Call us on 01270 442442 or 07771 903612, or email info@envirocareom.com. We cover Cheshire, the North West and North Wales.