EIA screening at 150 dwellings and five hectares

The EIA screening threshold for housing is not 150 dwellings. It is more than 150 dwellings, and that single word has decided more than one screening opinion. Paragraph 10(b) of Schedule 2 to the Town and Country Planning (Environmental Impact Assessment) Regulations 2017 covers urban development projects, and it is reached where the development includes more than one hectare of urban development that is not dwellinghouse development, or more than 150 dwellings, or where the overall area of the development exceeds five hectares.

Those limbs are alternatives. Any one of them brings the scheme into Schedule 2, which means screening is required. None of them makes the scheme EIA development.

Where housing sits in the two schedules

Schedule 1 lists projects for which assessment is mandatory, and residential development is not among them. Crude oil refineries, nuclear installations, long distance railways, large intensive livestock installations. No housing scheme, however large, falls into Schedule 1 by virtue of being housing.

So every residential screening question runs through Schedule 2. The schedule works in two columns, the description of development and the applicable thresholds and criteria, and a project is Schedule 2 development only where it is of a listed description and it meets or exceeds a threshold or is in a sensitive area. Housing almost always arrives through category 10(b).

Mixed schemes need care. A development of 120 dwellings with 3,000 m2 of commercial floorspace on a 4 hectare site has not passed the dwelling limb, but the commercial element may cross the one hectare limb for urban development that is not dwellinghouse development, and the five hectare overall area limb is measured across the whole red line rather than the built part. Measure all three before concluding anything.

The three limbs, read precisely

The overall area limb catches far more housing schemes than the dwelling limb. At typical suburban densities, 150 homes sits on something between four and eight hectares once roads, public open space and drainage are included, so an edge of settlement scheme of that size is usually in Schedule 2 on area even where the unit count stops at 150.

Draw the red line before you count. Where a site is being brought forward in phases under separate applications, the authority is entitled to consider the development as a whole rather than phase by phase, and salami slicing to stay under a threshold is a well recognised failure. Scale thresholds in obligations and the levy behave differently, which is why the same red line can give different answers for different purposes.

Asking for a screening opinion

You can ask the local planning authority for a screening opinion before submitting an application, and on a scheme of this size you should. The request has to describe the development and its location, with a plan sufficient to identify the land, and a description of the likely effects on the environment. In practice a short report of ten to twenty pages with a constraints plan does the job.

The authority has three weeks to adopt its opinion, extendable where it reasonably requires more information. It must give reasons either way, and where it concludes that assessment is not required those reasons have to address the Schedule 3 criteria rather than simply recording the conclusion.

Where no screening opinion has been sought and the authority considers the application may be Schedule 2 development, it will screen the application itself. That is the worse route, because it happens after validation and the clock is already running. And if the opinion comes back positive at that point, the application has to be withdrawn or suspended while an Environmental Statement is prepared, which on a scheme needing seasonal survey data can mean a year.

The Schedule 3 criteria that decide it

Schedule 3 sets the selection criteria, and the structure is worth learning because it also tells you how to write the request. Characteristics of the development, including its size and design, cumulation with other existing and approved development, use of natural resources, waste, pollution and nuisance, the risk of major accidents and risks to human health. Location of the development, covering existing land use, the abundance and quality of natural resources in the area, and the absorption capacity of the natural environment. Then the type and characteristics of the potential impact, including its extent, magnitude, duration, frequency, reversibility and cumulative nature.

Cumulation is the criterion most often skipped and the one most often raised by objectors. If three other schemes in the same catchment are approved and unbuilt, the request has to say so and explain why the combined effect still does not require assessment.

The test throughout is whether the development is likely to have significant effects on the environment by virtue of factors such as its nature, size or location. Mitigation can be taken into account, but only where it is certain and secured, so a request that leans on measures still to be designed is weak. An Environmental Impact Assessment has to be prepared by competent experts under the 2017 Regulations, and that requirement applies to the Environmental Statement itself rather than to the screening request.

Negative screening and the challenge risk

A negative screening opinion is the outcome most applicants want and the one that carries residual legal risk. The opinion can be challenged by judicial review, and a claim concerning a decision under the planning Acts generally has to be brought within six weeks, so the window is short but real. The challenge is to the adequacy of the authority's reasoning rather than to the merits of the development.

Reduce the exposure in two ways. Make sure the opinion engages with each Schedule 3 criterion that is live on your site, and keep the request and the opinion consistent with the application that follows. A scheme that grows from 148 to 162 dwellings between screening and submission has outgrown its opinion, and the sensible step is to go back for a fresh one rather than hope nobody checks.

A permission granted for EIA development without an Environmental Statement is vulnerable. That is the risk being managed, and it sits with the developer long after the decision notice is issued.

When volunteering an assessment is the safer route

Occasionally the right answer is to stop arguing and assess. Three situations push that way. The site has a designated interest close by and the likely effect is arguable on the evidence. The authority has signalled that it will screen positively. Or the scheme is politically contested and an objector with resources is already engaged.

The trade is real. Assessment brings a formal scoping stage, publicity requirements, a 16 week determination period instead of 13, and a substantial evidence cost. What it buys is a decision that is much harder to unpick, plus a structured scoping opinion that tells you exactly what the authority wants assessed. In London, where the referable thresholds bring a second decision maker into the process, that certainty can be worth more than the saving, and the Greater London Authority referral thresholds are a separate layer to check.

Timing the request in the programme

Put the screening request in after the constraints work and the first layout, and before the technical consultants are instructed in full. Too early and you cannot describe the development. Too late and the scoping opinion arrives after the surveys have been commissioned to the wrong brief.

A workable order for a 150 home scheme: designation and constraints check, indicative layout and red line, screening request, screening opinion, then scoping request if positive, then survey commissions aligned to the scoping opinion, then the Transport Assessment and the rest of the technical work. This is general guidance, not legal advice, so check the position with your local planning authority or a qualified professional before relying on it, and read the current consolidated version of the 2017 Regulations rather than a summary.

Enter your postcode on PlanScope to see which reports a scheme at this scale is likely to need, then draft the narrative documents and send the technical ones for professional review.

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