Septic tank compliance checker
Answer a few questions to see whether your septic tank or sewage treatment plant meets the Environment Agency's General Binding Rules — and what to do if it doesn't. Free, plain-English, no email required to get your result.
Where does your wastewater end up?
The single most important question under the General Binding Rules.
How the rules work, in brief
Off-mains drainage in England is governed by the General Binding Rules. The headline points: a septic tank must not discharge to a surface water (banned since 2020); discharge to the ground must go through a proper drainage field and stay under 2 m³/day; discharge to surface water must come from a sewage treatment plant under 5 m³/day. Where a mains sewer is within reach you may be required to connect instead.
Not sure where you stand near Cornwall? Call 01872 000000 and we'll talk it through.
Common questions
What are the General Binding Rules for septic tanks?
They are the Environment Agency rules (England) that let you discharge treated sewage from a small system without a permit, provided you meet set conditions — including how and where you discharge, volumes, and maintenance.
Is it illegal to have a septic tank that discharges to a stream?
Since 1 January 2020 you must not discharge from a septic tank directly to a surface water such as a stream, river or ditch. Systems that do must be replaced or upgraded — usually to a sewage treatment plant, or by adding a drainage field.
Do I have to upgrade my septic tank when I sell my house?
If your septic tank discharges to a watercourse, it must be brought into compliance as a condition of the sale. It is worth checking early so it does not hold up a sale.