Submitting a surface water drainage strategy: guidance

A surface water drainage strategy shows how surface water will be managed within a development so it does not increase flood risk elsewhere.

You’ll need to include this with your planning application for any:

• minor developments (fewer than 10 dwellings) within an area liable to flood from surface water or groundwater or that are likely to increase flood risk locally
• major developments (over 10 dwellings)
• developments that need sustainable drainage solutions to be provided

They are not required for householder development.

View our guidance for submitting a surface water drainage strategy.

We offer pre-application advice for minor, major and large-major developments.

This is the most efficient and cost-effective approach as it prevents delays within the planning process.

You can request:

• a meeting at County Hall
• a site visit (or meeting at an external office)
• written advice

Request pre-application advice

Pre-application advice is a charged service. For more information, see our terms and conditions.

You’ll need to submit a surface water drainage strategy with your planning application, via the planning portal.

The Local Planning Authority will consult the sustainable drainage team for their advice.

They are required to return their decision on the strategy within 21 days to the planning team.

This advice is based on:

If the strategy meets the necessary policies and guidance, we’ll recommend that the development is approved on surface water drainage grounds.

There may be planning conditions associated with these approvals. This is to make sure that the detailed design of the surface water drainage scheme meets the appropriate standards.

If the strategy does not meet the necessary policies and guidance, we’ll recommend the development be refused on surface water grounds.

Under guidance from the planning team, we’ll work with applicants to resolve these concerns where possible.

In determining an application, the planning team must be satisfied that surface water drainage strategy has:

• appropriate proposed minimum operation standards
• maintenance arrangements in place to ensure an acceptable standard of operation for the lifetime of the development
• provision for multifunctional benefits (where possible)

As the LLFA, we’ll comment only on surface water drainage matters.

Other sources of flood risk are the responsibility of other statutory consultees. For example, the Environment Agency will advise the LPA on planning applications on fluvial flood risk grounds for sites within Flood Zone 2 and 3.

To understand the statutory consultees for other sources of flood risk, review Schedule 5 of the Town and Country Planning (Development Management Procedure) (England) Order 2010).

Other risk management authorities may comment on a planning application if it falls within their administrative boundaries, but they are not statutory consultees. This may include water companies and the Internal Drainage Board.

If you have any questions, email [email protected].

We have a focus on incorporating sustainable drainage (SuDS) into new developments. This is in line with Paragraph 169 of the National Planning Policy Framework (2021) and local policy.