Since 1 January, 2015 it has not been permissible for new septic tanks to discharge into surface-waters (essentially streams, rivers and lakes) however, an exemption was provided for existing, non-polluting, septic tanks, but this exemption expires on 1 January, 2020, by which stage any such systems must be upgraded under the ‘General Binding Rules’ enforced by the Environment Agency.

The change will affect any Owner whose property uses a septic tank, shares the use of a tank with another property, or has responsibility for such an installation under a written agreement. It is important to note that the new rules do not apply to septic tanks which discharge to the ground, and one of the ways of satisfying the new requirements (where connection to a main sewer is not possible) is to install a drainage field to take any surface-water discharge, or to replace the system with a “small sewage treatment plant”, or to apply for a permit from the Environment Agency, however, that will only be granted in exceptional circumstances. 

The arrangements only apply to domestic, non-polluting, facilities which comply with British Standards when installed. 

If you are intending to purchase a property with a surface-water discharging tank, it is clearly important to ensure that the cost of any required changes form part of your purchase negotiations.