Defining a sequential test search area on a rural site

The sequential test for flood risk is lost on the area of search more often than on the sites. Define the search area too narrowly and the officer rejects the test as self-serving. Define it too widely and you hand objectors a list of alternatives you then have to discount one by one.

On a rural site the problem is sharper, because the catchment for the proposed development is rarely a neat administrative boundary and the evidence base of available sites is thinner than in a town.

Setting the area of search

National guidance leaves the area of search to be defined by local circumstances relating to the catchment for the type of development proposed. That phrase does the heavy lifting, and it is where the argument starts.

Three things shape it in practice. The type of development, because a rural exception affordable housing scheme serves a parish while a distribution unit serves a region. The policy basis for the proposal, because a scheme justified by a functional rural need has an inherently narrow catchment. And the authority's own evidence base, because a test carried out across an area the council has never assessed produces nothing an officer can check.

Write the justification before you list a single site. Two paragraphs explaining why the catchment is what you say it is will carry the whole test if they are sound, and no amount of site analysis will save them if they are not.

Agreeing it with the authority first

Send the proposed area of search to the case officer, in writing, before the work is done. Ask for confirmation or a counter-proposal.

This costs one email and saves the most common failure, which is a complete test submitted against an area the council then rejects. If the officer will not commit, record that you asked and proceed on a stated basis, because a documented attempt to agree the scope is itself evidence of reasonableness.

Raise it at pre-application where a pre-application service exists. An officer who has already accepted the search area in writing is unlikely to reopen it at committee.

Identifying reasonably available sites

A site is reasonably available if it could realistically be developed for the proposed use within the relevant period. The starting point is the authority's own evidence, which usually means the strategic housing land availability assessment or its equivalent, the brownfield land register, and current allocations in the adopted plan and any emerging plan.

Add sites that are publicly on the market for the relevant use, and any site an objector has previously raised in the area. Leaving out a site everybody knows about is worse than including it and explaining why it does not work.

Record for each site the source, the reference, the date of the data and the flood zone taken from the published flood map for planning. Dates matter because availability changes, and a test built on a three-year-old assessment invites the response that it is out of date.

An illustrative worked example

The following example is illustrative only. It is not a real site or a real decision, and the figures are chosen to show the method.

A scheme for eight dwellings is proposed on the edge of a village, partly within Flood Zone 2. The applicant proposes an area of search covering the parish and the two adjoining parishes, on the basis that the scheme responds to a locally evidenced need identified in the neighbourhood plan.

Three sites survive the first pass, and each then needs a reasoned conclusion on availability, suitability and achievability. The former depot is assessed as constrained by known contamination requiring remediation that the promoter has confirmed is not viable at the scale proposed. The allocated site is under an option to a housebuilder with a live reserved matters application, so it is not available for this proposal. The land north of the village hall is in the ownership of a party who has confirmed in writing that it is not for sale.

That written confirmation is what turns an assertion into evidence. Without it, the site stays on the list.

Discounting sites defensibly

Ownership preference is not a reason. Neither is the fact that the applicant does not control the land, taken on its own, because the test asks whether a site is reasonably available for the development rather than available to this applicant.

What works is specific, dated and checkable. A written response from the landowner or their agent. A published constraint such as a designation, an access limitation or a live permission for another use. A viability position supported by evidence rather than by assertion. A physical constraint recorded on a plan.

Keep the reasoning proportionate to the site. A two-hectare allocation deserves a paragraph. A garden plot too small for the proposal deserves a line.

And resist the temptation to over-argue. A test that discounts fifteen sites with fifteen equally emphatic reasons reads as advocacy, and an officer who spots one weak discount will look harder at the rest.

Recording the evidence trail

The test is a document that someone else has to be able to audit, possibly at appeal two years later.

Keep the search area justification, the site schedule with sources and dates, the correspondence with landowners and agents, the flood zone evidence for each site, and the email agreeing the search area. Reference each item in the sequential test itself rather than holding it in a project folder.

Screenshot the flood map for each site with the date visible. Mapping is updated, and a site shown in Zone 1 today may be mapped differently when the appeal is heard.

Keep the discarded material too. A site you looked at and removed early, because it turned out to be in the same flood zone as the application site, is worth a line in the schedule so that nobody later suggests it was overlooked.

Where the test is passed and what follows

Passing the sequential test means no reasonably available sites in areas at lower flood risk are appropriate for the proposed development. Say that in one sentence and support it with the schedule.

If the site sits in a flood zone where the exception test applies to development of that vulnerability, move on to it rather than treating the sequential test as the finish line. The exception test has two limbs, both of which must be satisfied, and the second of them depends on a site-specific flood risk assessment that models the proposal with the current climate change allowances applied.

Put the conclusion and the cross-reference in the planning statement as well. Officers assemble the recommendation from the planning statement, and a flood conclusion buried in a technical appendix sometimes never reaches it.

This is general guidance, not legal advice. Flood risk policy, mapping and climate change allowances are updated, so check the current position with your local planning authority, the Environment Agency or a qualified professional before relying on it.

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