Sustainable drainage in planning

As the Lead Local Flood Authority (LLFA) we can give you information and advice if you are preparing a planning application.

Sustainable drainage systems (SuDS) aim to manage rainwater runoff in a natural way by replicating natural processes.

Examples of SuDS provisions include:

  • green roofs
  • permeable pavement and underground storage
  • ponds
  • shallow ditches or swales
  • soakaways
  • wetlands.

For advice or information email

We provide pre-application advice for a fee on surface water drainage management, SuDS and drainage strategies for most major developments.

Our advice can:

  • indicate whether a drainage proposal would be unacceptable, saving you the cost of applying formally
  • reduce the time your advisers spend on developing a drainage strategy
  • ensure your drainage submission is complete so it doesn't get rejected in the early stages
  • let you know how guidance and policies will be applied to your development
  • identify whether you need specialist input.

For minor developments we provide free standing advice on incorporating sustainable drainage.

Advice on forms

Call 03000 41 41 41 or email for free, informal advice on the forms you need.

Download our pre application advice guidance (PDF, 494.6 KB) for further information.

Chargeable advice

To apply for chargeable planning advice please complete our flooding and drainage pre-application advice form.

Surface water management pre-application advice fees

All fees include VAT:

  • written advice for a general site enquiry or flood risk assessment enquiry - £240
  • meeting at County Hall - £360
  • meeting on site - £480
  • further written advice after meetings - £180
  • any additional correspondence (price upon application as it depends upon complexity of request).

We are also able to provide pre-application advice on land drainage, which is a separate service. Meetings with both our SuDS team and land drainage engineer can be arranged, enabling you to have an in depth discussion about the drainage issues of your site.

Surface water management and land drainage pre-application advice fees

All fees include VAT:

  • meeting at County Hall / online meeting - £540
  • meeting on site - £720.

We also offer chargeable advice for county planning and highways matters.

Download our full drainage planning fees (PDF, 241.8 KB).

Read the full guidance for master planning sustainable drainage into developments (PDF, 4.5 MB), or choose which section you would like to read:

Our surface water management plans should also be referred to during the formulation of a drainage strategy for a site.

Land drainage consents

Any feature on site that is not an Environment Agency designated ‘main river’ that is capable of conveying flow would be classified as an ‘ordinary watercourse’ (such as ditches, dykes and streams). Any works within the channel of any such feature would require our formal written consent.

If any part of a development or its associated drainage system involves works to an existing ordinary watercourse, please see our guidance on land drainage consent.

Statutory consultee role

Find out more about our statutory role to provide technical advice and guidance on the surface water drainage strategies, designs and maintenance arrangements put forward by developers for any new major development through our statutory role.

New developments

The provision of sustainable drainage within new development became a material consideration in planning decisions from 15 April 2015.

As Lead Local Flood Authority and statutory consultee, we review drainage strategies and surface water management provisions associated with major development. This means that we must be consulted by each of the Kent's 12 local planning authorities whenever they receive an application for major development (PDF, 93.1 KB) within their district.

Read our sustainable drainage chapter of the 'Making it Happen - Kent Design Guide (PDF, 2.8 MB)' (chapter 2). The design guides sets the standards and provide detailed design details for drainage systems which are adopted by us, specifically those associated with highways.

Not all planning applications require detailed information. Some forms of development would be considered to be relatively ‘low risk’ provided it can comply with our following standing advice:

For further information about standing advice, please email