Sustainable drainage systems and the planning process

National planning policy and guidance sets a clear expectation for developers to provide sustainable drainage systems (SuDS) which include benefits for water quantity, water quality, biodiversity and amenity.

Multifunctional sustainable drainage systems are those that deliver a wider range of additional biodiversity and environmental net gains such as those set out in the Planning Practice Guidance. Lancashire County Council strongly encourages the design of multifunctional sustainable drainage systems that integrate with blue and green infrastructure.

In doing so, developers must consider the requirements set out in:

What to provide

The County Council expects applicants to provide information on their sustainable drainage proposals in the following documents:

Where sustainable drainage systems are considered to be inappropriate, applicants must provide clear evidence to justify this.

Lead Local Flood Authority (LLFA) planning advice service for surface water and sustainable drainage

Applicants for planning permission can seek advice from the Lead Local Flood Authority regarding their major development proposals for surface water and sustainable drainage systems.

This chargeable service allows applicants to obtain advice from the Lead Local Flood Authority:

  • At pre-application stage
  • for the discharge of conditions relating to surface water and/or sustainable drainage systems which the Lead Local Flood Authority recommended
  • in relation to an objection by the Lead Local Flood Authority where the applicant is seeking more advice than is provided in the objection letter about how to overcome the objection.

Works on or near to watercourses

If you are looking to carry out construction work or make alterations to a watercourse you may need to get permission from the relevant regulator.

  • If the watercourse is classified as a 'main river' you may need to apply for an Environmental Permit from the Environment Agency.
  • If the watercourse is classified as 'ordinary' you may need to apply for Ordinary Watercourse Consent from Lancashire County Council as the Lead Local Flood Authority.

Planning permission does not grant a developer any permission for works affecting watercourses. This is separate regulatory process.

Failure to obtain the relevant permission for watercourses may impact on the adoption of sewers by the Water and Sewerage Company and/or the adoption of a road by the County Council as the Highway Authority.


Flood Risk Management Team
Lancashire County Council
Highways Department
Cuerden Offices
Bamber Bridge

Tel: 0300 123 6780