Sustainable Drainage Systems

Sustainable drainage systems explained

Sustainable drainage systems, often referred to as SuDS, is a drainage solution designed to control surface run off close to where it falls and mimics natural drainage as closely as possible. Sustainable drainage systems provide opportunities to reduce the causes and impacts of flooding; remove pollutants from urban run-off at source; and, combine water management with green space with benefits for amenity, recreation and wildlife.

Planning application requirements

From 6 April 2015 all planning applications (including outline submissions) for major developments will be required to show that sustainable drainage systems for the management of run-off are put in place, unless demonstrated to be inappropriate. This was first announced by a Written Ministerial Statement by the Secretary of State for Communities and Local Government on the 18 December 2014. Under these national arrangements, from the 15 April 2015 the Lead Local Flood Authority (LLFA) i.e. Surrey County Council will be a statutory consultee on these applications.

From 6 April 2015 we require all new planning applications to be supported by a Sustainable drainage statement. To assist with this the following advice note and pro-forma has been prepared, in collaboration with other Surrey authorities.

In considering major planning applications, we must satisfy ourselves that the proposed minimum standards of operation are appropriate and ensure, through the use of planning conditions or planning obligations, that there are clear arrangements in place for ongoing maintenance over the lifetime of the development.

For this reason, failure to provide the necessary drainage information may result in a refusal of your planning application and so it is in your interests to complete the pro-forma and provide the Sustainable Drainage Statement at the time of submission.

Designing a Sustainable Drainage System

It is advisable that you use the Drainage Statement pro-forma and consult with the LLFA as part of the pre-application process. To consult the LLFA please email

The Government has issued technical standards relating to the design, construction, operation and maintenance of a sustainable drainage system.

Further Information

Water. People. Places. A guide to masterplanning sustainable drainage into development