Guidance

National flood risk standing advice for local planning authorities

When to use standing advice on site-specific flood risk assessments, and when to consult the Environment Agency.

Applies to England

For some developments you must consult one or both of :

  • the Environment Agency
  • the lead local flood authority (LLFA)

For other developments you must use the flood risk standing advice in this guide. This guide applies to the following application types:

  • full
  • outline
  • reserved matters
  • change of use
  • prior approval for flood risk under certain permitted development rights
  • permission in principle
  • technical details consent

You must also consult the Environment Agency on a range of other issues. These are set out in .

Other risk management authorities may also ask you to consult them. For example:

  • the Internal Drainage Board (IDB) when development is in an internal drainage district (IDD) 바카라 사이트 see the
  • the water and sewerage company when sewer flooding may be an issue 바카라 사이트 check to

Planning applicants can find advice onflood risk assessments if you are applying for planning permission.

Local planning authorities can find advice on how to prepare a strategic flood risk assessment (SFRA).

Research the development site

  • use the to find if the development is - in Flood Zone 1, 2 or 3 - within 20 metres of a main river or a flood defence - in a water storage area 바카라 사이트 at risk of surface water flooding 바카라 사이트 at risk of flooding from rivers and sea now or in future due to the possible effects of climate change
  • find out whether the development is in - note these are currently only designated in and , contact the Environment Agency if you are unsure
  • check your SFRA to find out if the development is - in Flood Zone 1 now but will be at risk of flooding from rivers or the sea during its lifetime - in Flood Zone 3b (functional floodplain) - at risk from sources of flooding other than rivers or sea
  • establish the site area and check the development class
  • find out the vulnerability classification
  • use the following guidance to work out whether you need to consult or follow the standing advice
  • follow the guidance on shown on the flood map for planning

Material displayed on the is provided without any guarantees, conditions or warranties as to its accuracy. This includes maps and risk data. See our바카라 사이트바카라 사이트for more information.

Check the development class

Major development involves one or more of the following:

  • providing 10 or more dwellinghouses defined in of the DMPO or, where the number of dwellinghouses is not known, the site area is 0.5 hectares or more
  • providing a building or buildings where the floor space to be created by the development will be 1,000 square metres or more
  • development on a site of 1 hectare or more
  • the winning and working of minerals or the use of land for mineral - working deposits
  • waste development

A minor development is:

  • development of an existing dwellinghouse, or development within the curtilage of a dwellinghouse, for any purpose incidental to the enjoyment of the dwellinghouse
  • an extension to an existing building used for non-domestic purposes where the floor space created by the development does not exceed 250 square metres
  • alterations to an existing building which do not increase the size of the building

Non-major development is any development not falling into the major or minor development classes.

Check if a flood risk assessment is needed and if one is provided

Before you validate the application, you should check if a flood risk assessment (FRA) is needed and if one is provided.

바카라 사이트FRA바카라 사이트should be completed for all development:

  • within Flood Zones 2 or 3 - see
  • within Flood Zone 3b
  • within Flood Zone 1 with a site area of 1 hectare or more
  • within Flood Zone 1 and the shows it is at increased risk of flooding from rivers or sea during its lifetime
  • with Flood Zone 1 and the shows it is at risk of flooding from surface water
  • within areas with critical drainage problems
  • within Flood Zone 1 where yourSFRAshows it will be at increased risk of flooding during its lifetime
  • that increases thevulnerability classificationand may be subject to sources of flooding other than rivers or sea

Check if information on sustainable drainage systems is needed and if it is provided

Before you validate the application, you should check if a sustainable drainage strategy is needed and if one has been provided.

A sustainable drainage strategy is needed for all development:

  • which could affect drainage on or around the site
  • in an area at risk of flooding such as Flood Zones 2 or 3, or at risk of surface water flooding

Wherever possible, the Sustainable Drainage System (SuDS) will need to provide multifunctional benefits, including for:

  • water quantity
  • water quality
  • biodiversity
  • amenity

More information on multifunctional benefits can be found in what are sustainable drainage systems and why are they important?

The sustainable drainage strategy will need to include all the information set out in what information on sustainable drainage needs to be submitted with a planning application? The strategy could be a separate document or part of theFRA, where relevant.

To ensure an acceptable standard of operation for the lifetime of the development, SuDS for major development will need to have:

  • appropriate minimum operational standards
  • maintenance arrangements

Check to see if you (or theLLFA) have local guidance on SuDS with additional information requirements.

The sequential and exception tests

When the sequential test is needed

sequential testis required for major and non-major development (check the development class section above) if any proposed building, access and escape route, land-raising or other vulnerable element will be:

  • in Flood Zone 2 or 3
  • in Flood Zone 3b and your development is not incompatible
  • within Flood Zone 1 and the shows it is at increased risk of flooding from rivers or sea during its lifetime
  • with Flood Zone 1 and the shows it is at risk of flooding from surface water
  • in Flood Zone 1 and yourSFRAshows it will be at increased risk of flooding during its lifetime
  • subject to sources of flooding other than rivers or sea

A development is not exempt from the sequential test just because a flood risk assessment shows the development can be made safe throughout its lifetime without increasing risk elsewhere.

See what the aim of the sequential approach is.

When development is exempt from the sequential test

A development is exempt from the sequential test if it is a:

  • householder development like residential extensions, conservatories or loft conversions
  • small non-domestic extensions with a footprint of less than 250 square metres
  • change of use (except changes of use to a caravan, camping or chalet site, or to a mobile home or park home site)

A development is also exempt from the sequential test if it is a development on a site allocated in the development plan through the sequential test and:

  • the proposal is consistent with site바카라 사이트s allocated use
  • there have been no significant changes to the known level of flood risk to the site, now or in the future, which would have affected the outcome of the test

You may not need a sequential test if development can be laid out so that only elements such as public open space, biodiversity and amenity areas are located in areas at risk of any source of current or future flooding.

How to apply the sequential test

You should speak to the applicant early to discuss the sequential test and determine an appropriate area of search for the test. You should consider whether the test is passed, with reference to the information you hold on land availability.

You may also need the applicant to:

  • include information to identify any other 바카라 사이트reasonably available바카라 사이트 sites that you have not already identified - this could include sites currently available on the open market
  • check on the current status of alternative sites to determine if they are 바카라 사이트reasonably available바카라 사이트 - refer to guidance on바카라 사이트applying the sequential test to individual planning applications

When the exception test is needed

The exception test is needed for development with a바카라 사이트vulnerability classification바카라 사이트o:바카라 사이트

  • 바카라 사이트highly vulnerable바카라 사이트 - in Flood Zone 2
  • 바카라 사이트more vulnerable바카라 사이트 - in Flood Zone 3a
  • 바카라 사이트essential infrastructure바카라 사이트 - in Flood Zone 3a or 3b

How to apply the exception test

Refer to:

The applicant needs to provide the evidence you need to check if both parts of the exception test have been satisfied.

You should refuse permission if the sequential and exception tests, where relevant, are not done or not satisfied.

When to consult the lead local flood authority

For major development with surface water drainage, you must consult your LLFA.

For other developments with surface water drainage, you should check if there is:

  • a local consultation arrangement with your LLFA
  • local guidance on SuDS you should follow

For developments that will increase the vulnerability classification and where your SFRA or the shows it is at risk from sources of flooding other than rivers or sea:

  • make sure the applicant provides a FRA
  • check if there is a local consultation arrangement with your LLFA
  • ask your LLFA if you should consult it

When to consult the Environment Agency or follow standing advice

Flood Zone 1

When to consult the Environment Agency

You must consult the Environment Agency if the proposed development (including change of use) is:

  • within 20 metres of a main river -
  • in an area with critical drainage problems, other than minor development - check the development class section above

When to follow standing advice

Check yourSFRAand the to see if the site will be at increased risk of flooding from rivers or the sea in future. If it will be, you should:

  • make sure aFRAis provided
  • treat the site as if it were in Flood Zone 2 when deciding whether to consult the Environment Agency or follow standing advice

Flood Zone 2

When to consult the Environment Agency

You must consult the Environment Agency if the proposed development is(including culverted main rivers). This includes change of use and minor development - check the development class in the above section.

You must also consult the Environment Agency if the development will have a바카라 사이트vulnerability classification바카라 사이트of:

  • 바카라 사이트essential infrastructure바카라 사이트
  • 바카라 사이트highly vulnerable바카라 사이트
  • 바카라 사이트more vulnerable바카라 사이트 and it바카라 사이트s a landfill, waste facility site, caravan or camping site
  • 바카라 사이트less vulnerable바카라 사이트 and it바카라 사이트s a waste treatment site, mineral processing site, water treatment plant, or sewage treatment plant

This includes change of use but excludes minor development - check the development class in the above section.

When to follow standing advice

You must refer to standing advice for vulnerable developments바카라 사이트when the proposed development (including change of use) will have a바카라 사이트vulnerability classification바카라 사이트of:

  • 바카라 사이트water compatible바카라 사이트 - including essential accommodation within a water compatible development
  • 바카라 사이트more vulnerable바카라 사이트 - and not a landfill, waste facility site or a caravan or camping sitewhere the Environment Agency should be consulted
  • 바카라 사이트less vulnerable바카라 사이트 - and not a waste treatment site, mineral processing site, water treatment plant, or sewage treatment plantwhere the Environment Agency should be consulted

Refer to바카라 사이트advice for minor extensions바카라 사이트for householder or non-domestic extensions with a floor space of no more than 250 square metres.

Flood Zone 3 or 3b

When to consult the Environment Agency

You must consult the Environment Agency on:

  • development (including change of use) proposed within 20 metres of a main river
  • development other than minor development (check the development class in the above section)

Changes of use where the vulnerability classification will:

  • be 바카라 사이트more vulnerable바카라 사이트 or 바카라 사이트highly vulnerable바카라 사이트
  • change from 바카라 사이트water compatible바카라 사이트 to 바카라 사이트less vulnerable바카라 사이트

When to follow standing advice

Refer to advice for minor extensions for household or non-domestic extensions with a floor space of no more than 250 square metres.

Table 2 of the planning practice guidance states you should not permit development in Flood Zone 3b if its vulnerability classification will be:

  • 바카라 사이트highly vulnerable바카라 사이트
  • 바카라 사이트more vulnerable바카라 사이트
  • 바카라 사이트less vulnerable바카라 사이트

Tell the applicant about other permits or consents

You should tell the applicant to check if they need a separate permit or consent. They may need one if the development:

  • is within 20 metres of a main river, flood defence or flow control structure
  • directly affects a watercourse that is not a main river
  • involve activity in the floodplain of a main river which could affect flood flow or storage, for example land raising, and potential impacts are not controlled by a planning permission
  • are covered by regional flood defence and land drainage byelaws, where these are applicable

If any of these applies to the development, tell the applicant to refer to check if you need permission to do work on a river, flood defence or sea defence. They should do this as soon as possible as it will tell them if they need an extra permit or consent and who to contact.

Applicants can check if their development activity and location are covered by regional flood defence and land drainage byelaws by referring to this statutory guidance.

If there is a watercourse (including culverted watercourses) on or near the development site, you should also advise the applicant to read:

These will enable them to understand their responsibilities and the rules they need to follow.

In some cases, we may recommend that the applicant applies for planning permission at the same time as other permits or consents. This will help to resolve complex permitting issues at the same time as decision making for the planning process.

Flood risk permits or consents are often needed as well as planning permission. Getting planning permission does not guarantee they will also get a flood risk permit or consent.

What you need to check in an assessment

FRAs바카라 사이트should be:

  • appropriate to the scale, nature and location of the development
  • proportionate to the degree of flood risk

FRAs should appraise the suitability of the flood risk datasets it has used. This should take account of:

  • when the dataset was produced
  • why the dataset was produced
  • the limitations of the dataset

FRAs should contain the information set out in ٳ바카라 사이트site-specific flood risk assessment check-list.

When reviewing바카라 사이트FRAs, you should check whether:

  • all sources of flood risk affecting the proposed development now and throughout its lifetime have been assessed
  • ٳ바카라 사이트development type is incompatible바카라 사이트with the proposed location
  • the measures proposed will make the development safe throughout its lifetime
  • the proposed development will be appropriately flood resistant and resilient
  • the proposed development will increase flood risk elsewhere and, if so, that appropriate mitigation has been included
  • the site has been laid out, so the most vulnerable aspects of the development are located in areas of lowest flood risk
  • any residual risks can be safely managed
  • safe access and escape routes are included where appropriate, as part of an agreed바카라 사이트
  • the proposed development incorporates SuDS

You should make sure that any mitigation measures included in the FRA and standing advice are secured in any planning permission using appropriately worded planning conditions. Conditions should list all necessary mitigation measures rather than just requiring implementation of the FRA. For example, finished floor levels shall be set at a minimum level (insert relevant value) metres above Ordnance Datum.

Updates to this page

Published 15 April 2015
Last updated 10 April 2025 show all updates
  1. Amended to signpost to new guidance on how to use the flood risk datasets shown on the Flood Map for Planning. Provided additional guidance to ensure FRAs appraise the suitability of flood risk datasets before use.

  2. Amended to signpost new flood and coastal erosion risk data and provide advice on its use and to reflect revised policy on sustainable drainage systems in the December update to the National Planning Policy Framework

  3. Replaced 'apply this guidance as if the site were in flood zone 2' with 'treat the site as if it were in flood zone 2 when deciding whether to consult the Environment Agency or follow standing advice' - under 'when to consult the Environment Agency or follow standing advice' section (flood zone 1)

  4. Added link to 'your watercourse: rights and roles' under 'tell the applicant about other permits or consents' section.

  5. Amended title to better reflect content of the page, included more clarifications and updated sections with relevant links.

  6. Updated to improve clarity and reflect the latest National Planning Policy Framework. Clarified application types to which the standing advice applies. Included definitions for development classes to improve clarity. Improved links to strategic flood risk assessments. Greater clarity on the need for flood risk assessments, sustainable drainage information and sequential and exception test information. Highlight the need to check the compatibility of the proposed use with the flood zone. Highlighting that some developments may also need a flood risk activity permit.

  7. Guidance reviewed and no changes made.

  8. Correcting an omission in 바카라 사이트The sequential and exception tests바카라 사이트 section. Flood zones have been reinstated for the 바카라 사이트highly바카라 사이트 and 바카라 사이트more바카라 사이트 vulnerable flood risk vulnerability classifications for when an exception test should be done.

  9. Clarity improved and links updated. Clarified status of advice for minor extensions and change of use categories. Moved 바카라 사이트extra resistance and resilience measures바카라 사이트 section to 'Preparing a flood risk assessment: standing advice' guide. Included advice for areas of flood zone 1 that will be at future risk.

  10. Changed URL for "Find out what flood zone you바카라 사이트re in" to pint to new Flood Map for Planning service Changed URL for "Check if your development is within 20 metres (m) of a main river" to point to WIYBY Main River map

  11. First published.

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