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What you need to know about septic tanks and small sewage discharges come 2020…

We can totally relate with you that this isn’t the most pleasant of topics, however if you are looking to buy / sell / let, or if you own a residential property that is served by a septic tank, we encourage you to read on…

As per PropertyMark's latest update - From 1 January 2020, all septic tanks in England can no longer discharge untreated sewage into a watercourse. If your discharge causes pollution it may be considered an offence and can result in the Environment Agency taking enforcement action against you.

In 2015, the General binding rules for small sewage discharges were announced, aimed at those who discharge their sewage either into the ground or to surface water.


For those that have such sewage discharges, they must do the following before 1 January 2020:

• Work out your discharge amount with the discharge calculator

• Read and follow the General Binding Rules

• Check whether you have an existing discharge (a system installed and discharging before 31 December 2014) or a new discharge (system installed and discharging on or after 1 January 2015). New discharges have extra rules they must follow.

• Find out if you’re in a Source Protection Zone (SPZ) ◦Click the link above to the DEFRA magic map and search for your location in the top left

  • Click the tick box for ‘Designation’”, then the + on ‘Land-Based Designations’

  • Click the + on ‘Non-statutory’ and click the tick box for ‘Source Protection Zones’

  • If your area highlights in red, it is in an SPZ and won’t meet the General Binding Rules

•Update or change your sewage management system to follow the rules

•If you are unable to follow any of the rules, apply for an Environmental Permit

The ‘General binding rules: small sewage discharge to a surface water’ regulations were also announced, giving owners of septic tanks that release liquid into surface water until 1 January 2020 to make the necessary changes to comply.

The reason for the regulations is to prevent pollution and ensure that sewage is properly disposed of.

What are the changes?

If your septic tank currently releases untreated sewage into a watercourse, then you must change your sewage management to prevent this. You can do so in three ways:

  • Connect to a public/mains sewer (if possible).
  • Install a drainage field/soakaway to discharge the wastewater into the ground instead.
  • Install a sewage treatment plant instead of a septic tank to allow the water to be treated before being discharged into a watercourse.

For further information, please head to PropertyMark’s ‘advice and guides’ -