Rules for Septic Tanks Discharges Changing 1 January 2020

Living in the countryside, it is very common to have a septic tank as connection to mains drainage can be a long way away.

They can be a relatively easy solution so long as they are regularly emptied and maintained, but new General Binding Rules came into force in 2015 to regulate discharges from them.  This meant that existing and new discharges to a soakaway were no longer permitted and a “drainage field” had to be used instead, being a series of pipes with holes, placed in trenches, arranged so that the effluent can trickle through the ground for further treatment.

The rules are further tightened with effect from 1 January 2020 so that septic tanks which discharge directly into surface water will no longer be permitted. The operator must take action to replace or upgrade them by that date which might include connection to a mains sewer where available, installation of a drainage field or replacing the septic tank with a small sewage treatment plant.

Where a property with such a septic tank is to be sold before 1 January 2020, the question of responsibility for the necessary work should be addressed between the buyer and the seller as a Condition of the sale. 

There are additional rules for new discharges from a treatment system installed on or after 1 January 2015 including where there was a discharge before that date, but you wish to change it:

• if any part of the building the treatment plant serves is within 30 metres of a public sewer the Environment Agency will not allow a new discharge from a sewage treatment plant
• You must apply for planning permission and building regulation approval to install a new sewage treatment plant
• new discharges to ditches/surface water are only allowed if there is sufficient all year-round flow

 The Environment Agency has published further information on its website, including:

https://www.gov.uk/guidance/general-binding-rules-small-sewage-discharge-to-a-surface-water

https://www.gov.uk/guidance/general-binding-rules-small-sewage-discharge-to-the-ground