In a small hamlet located in Southern Cumbria we were recently contracted to install a new septic tank to serve the local community hall. The maximum capacity requirements for the new tank was to handle a maximum of 50 people at peak times using the WC, WHB and sink facilities.

The outside sewage works was one of the final elements to be completed after a few years renovation of the old building. For this project we recommended a Kingspan Klargester 2,800 litre Sigma shallow dig septic tank with a discharge to a drainage field.

Within our scope of works we were to pick up the exiting 110mm soil waste pipe exiting the village hall and install new inlet and outlet pipework (totalling 18 metres), along with the tank and drainage field installation. Based on the ground percolation and average flow from the site a drainage field size of 15m was required.

The drainage field comprised of 110mm slotted pipe, bedded and surrounded in a clean washed gravel in a 900mm wide trench. All our drainage field constructions are calculated as per BS EN6297. Within the British Water code of practise on this there are a number of elements to consider should you be looking at a Septic tank and drainage field option:

• Septic tanks can only discharge to ground via a drainage field and direct discharge to a watercourse is no longer compliant in regards to the General Binding Rules 2020.

• Drainage field can only be installed once the ground conditions and porosity have been confirmed as suitable (they can neither drain away to slow nor too quickly).

• The Drainage field has a few distance requirements for the installation, they need to be a minimum of 10m away from a watercourse (pond, river, ditch etc), 15m from a Building and 50m from a water abstraction point.

As this site ticked all the right boxes the septic tank was the ideal low cost solution for this village hall to get up and running.