Where flood risk applies in Lewisham
The council's Strategic Flood Risk Assessment sets out the main sources:
- The Ravensbourne, Pool and QuaggyAlmost all of the borough lies in the Ravensbourne catchment. River flooding is mainly associated with the Ravensbourne and its main tributaries, the Pool River and the Quaggy, and the Environment Agency's historic maps show significant flooding across the catchment in the 1960s.
- Deptford Creek and the ThamesNorth of Deptford Bridge the Ravensbourne becomes the tidal Deptford Creek, which meets the Thames about a kilometre further north. Tidal defences line both, but there is residual tidal flood risk in the areas around them.
- Functional floodplainThe SFRA identifies functional floodplain (Flood Zone 3b) on both the Ravensbourne and the Quaggy, notably near Ladywell and Lewisham town centre, and the flood storage area on the Quaggy in the south east of the borough.
- Surface waterThe Lewisham Surface Water Management Plan (2011) estimated 2,228 properties at risk of surface water flooding, 327 of them to a depth of 0.5 metres or more.
What London Borough of Lewisham will look for
London Borough of Lewisham applies the national tests in NPPF Chapter 18 and the Planning Practice Guidance, supported by its Strategic Flood Risk Assessment. A Sequential Test submitted with a Lewisham application should normally:
- Confirm the flood zone and vulnerabilityUse the current Environment Agency Flood Map for Planning and the NPPF Annex F vulnerability class for the proposed use.
- Justify the area of searchNational policy says the area of search should reflect the catchment for the type of development and the need it serves. For larger schemes in Lewisham that is usually the whole borough; for smaller schemes, the neighbourhood or town centre served, such as Lewisham, Catford, Deptford or Sydenham, is often more defensible.
- Assess the council's own sources of sitesthe Lewisham Local Plan site allocations (adopted July 2025), with each site's planning status from the plan, and the Brownfield Land Register are the obvious places to start, and omitting them is a common reason for challenge.
- Evidence every discounted siteWhere an alternative is ruled out as unsuitable, too small or not available in a similar timeframe, give the reason and the evidence. Ownership alone is not enough.
- Screen for the Exception TestState whether the Exception Test applies under Annex F Table 3, and if it does, provide it, drawing on the site-specific flood risk assessment.
Lewisham-specific pitfalls
- Functional floodplainMost housing is not appropriate in Flood Zone 3b. The Environment Agency's maps don't show it separately, so check the SFRA mapping early if your site is near the Ravensbourne or the Quaggy.
- Reliance on defencesDeptford is defended against the tide, but the Sequential Test uses flood zones as if the defences were not there. The defences matter for the site-specific flood risk assessment, not for choosing between sites.
- Allocations and planning statusOur reports use the Local Plan site allocations adopted in July 2025, with each site's planning status from the plan where we can match it, and leave out sites the plan records as under construction. A few allocations show no status and are flagged for you to check.
- Sites outside the allocationsLondon has no current borough land availability assessment, so sites outside the allocations are included only where they are on the brownfield register.
Fixed-fee Sequential Tests for Lewisham
We have built our Lewisham Sequential Test on published Environment Agency and London Borough of Lewisham data. Plot your site on our Lewisham Sequential Test page and we'll deliver a submission-ready report within 24 hours of payment for £300. Exception Tests are £450 within 48 hours.
New to the subject? Start with our general guide: what is a flood risk Sequential Test? We also cover other council areas at the same fixed fee. For wider planning help, see planning consultants in Lewisham.
Source: Lewisham Strategic Flood Risk Assessment (AECOM, Level 1, October 2018).
Sequential Test guides for other council areas
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Frequently asked questions
Does London Borough of Lewisham require a Sequential Test?
Yes, for most development in Flood Zones 2 and 3, in line with national policy. Some minor development and most changes of use are exempt, and sites allocated in the local plan may not need the test repeated.
What area of search should I use in Lewisham?
National policy says the area of search should reflect the catchment for the type of development and the need it serves. For larger schemes in Lewisham that is usually the whole borough; for smaller schemes, the neighbourhood or town centre served, such as Lewisham, Catford, Deptford or Sydenham, is often more defensible. The reason must be explained in the report.
Do flood defences mean I don't need a Sequential Test?
No. Flood zones for the Sequential Test are assessed without defences. Defences are taken into account in the site-specific flood risk assessment and the Exception Test, not the Sequential Test.
How much does a Sequential Test cost in Lewisham?
Our fixed fee for a Lewisham flood risk Sequential Test or alternatives assessment is £300, delivered within 24 hours of payment. An Exception Test is £450, delivered within 48 hours.
This guide is general information for applications in England and is not advice on your specific project. Requirements differ in Wales, Scotland and Northern Ireland, and every council publishes its own local validation list, so always check the detail with your local planning authority.