Which reports change at 150 units

At 150 dwellings two things happen that do not happen at 149. Active Travel England becomes a statutory consultee, and the scheme crosses into Schedule 2 of the Environmental Impact Assessment Regulations 2017, which makes a screening opinion a live requirement rather than an optional comfort. The reports needed for a 150 unit scheme therefore expand at both ends: more consultees to satisfy, and a formal decision to obtain about whether an Environmental Statement is needed at all.

Everything else that arrives at this scale is a consequence of those two, plus the ordinary weight of a large major application: health, equalities, landscape, phasing, utilities and social infrastructure.

Statutory consultees that arrive at this scale

The consultee list is set by Schedule 4 to the Development Management Procedure Order 2015 and by separate directions, and the additions at large major scale change the programme more than the documents.

Active Travel England is consulted on major applications at or above 150 dwellings, 7,500 m² of floorspace or five hectares of site area. It reviews walking and cycling provision against national design standards, and it scores schemes. Weak internal permeability, cycle parking in the wrong place or a site access that treats cyclists as an afterthought will draw comment that the highway authority then has to respond to.

Others that commonly arrive at this scale:

• National Highways, where the scheme affects the strategic road network, with the trip distribution and any junction capacity work needing to satisfy its own assessment expectations.
• The lead local flood authority as statutory consultee on surface water drainage for major development.
• The Environment Agency where flood risk, groundwater or a main river is involved.
• Natural England on protected sites, nutrient neutrality catchments and biodiversity matters.
• Sport England where playing field land is involved.
• The relevant water and sewerage undertaker on capacity and connection.
• In London, the Mayor, since schemes of 150 or more residential units outside central London are referable under the Mayor of London order.

Write to the ones you can approach before submission. A pre application position from Active Travel England or National Highways is worth more than an elegant response to their objection in week nine.

Screening for environmental impact assessment

This is the substantive change at 150 units. Schedule 2 of the 2017 Regulations captures urban development projects where the development includes more than 150 dwellings, where the site area exceeds five hectares, or where the overall floorspace exceeds one hectare for non residential development.

Crossing a Schedule 2 threshold does not mean an Environmental Statement is required. It means the question has to be answered, by reference to the selection criteria in Schedule 3: the characteristics of the development, its location and the types and characteristics of the potential impact.

Three routes, and the choice matters:

1. Request a screening opinion from the authority under regulation 6 before submitting. The authority must adopt an opinion within three weeks unless an extension is agreed, and a negative opinion gives you certainty to design the rest of the submission around.
2. Submit without screening and rely on the authority screening the application. Slower and riskier, because a positive screening opinion after submission can invalidate the application.
3. Volunteer an Environmental Statement without screening. Occasionally sensible on a highly sensitive site, and expensive if it was not necessary.

Almost always, request the opinion. And request it with a short, honest screening report attached: the site, the constraints, the sensitivities, and why no likely significant effects arise. Authorities screen more comfortably against evidence than against a blank request.

If the opinion is positive, the Environmental Impact Assessment route changes the project. The determination period becomes 16 weeks, a scoping opinion is worth obtaining under regulation 15, and the Environmental Statement must be prepared by competent experts under the 2017 Regulations. That is a legal requirement rather than a preference, and a drafted structure is a starting point for those experts rather than a substitute for them.

Health and equalities evidence

Large residential schemes increasingly attract requests for a health assessment. The basis is usually a local plan policy or a supplementary planning document rather than national policy, with thresholds set locally, and London boroughs have applied them longest.

A Health Impact Assessment at this scale looks at the determinants a housing scheme actually affects: housing quality and space standards, access to green space and play provision, active travel, food environment, air quality, noise, social connectivity and construction phase effects. The useful ones connect each finding to a design response and say who monitors it.

Equalities evidence is different in character. The public sector equality duty under the Equality Act 2010 falls on the authority, not on you. What an applicant can usefully supply is the material that lets the authority discharge it: accessible and adaptable dwelling numbers, wheelchair user dwelling provision against policy, step free access routes, and the accessibility of open space and play areas. Framing this as helping the authority meet its duty tends to get a better reception than framing it as your own assessment.

Landscape and visual impact work

At 150 units the site is usually large enough to change how a place is seen from outside it.

Where the scheme sits on an edge of settlement site, expect a Landscape and Visual Impact Assessment prepared to the third edition of the Guidelines for Landscape and Visual Impact Assessment, with agreed viewpoints, winter and summer cases where deciduous screening matters, and a cumulative section covering other consented and applied for schemes.

Where the site is within an urban area, townscape rather than landscape is the frame, and the assessment focuses on scale, height, roofline, materials and the experience of the street.

Either way, the document that persuades is the one whose mitigation is in the layout rather than at the boundary. A structural planting belt drawn after the plots are fixed reads as an afterthought, because it is one.

Phasing, construction management and traffic

A 150 unit scheme is built over years, in phases, and the application has to describe that rather than present a finished state.

What to include:

• A phasing plan, with the infrastructure and open space allocated to each phase rather than deferred to the last.
• A Transport Assessment covering the full scheme and the interim phases, because a phase with a single point of access can perform very differently from the completed layout.
• A travel plan with targets, a coordinator and monitoring, since at this scale a plan without measurement will not be accepted.
• A construction traffic management plan with routes, hours, wheel washing and a condition survey of the affected roads.
• A construction environmental management approach dealing with dust, noise, vibration and water pollution, referencing the relevant standards.

Conditions will tie occupation to delivery of infrastructure, so the phasing plan you submit becomes the framework for those conditions. Draft it as though it will be conditioned, because it will be.

Utilities, education and social infrastructure

The infrastructure work at this scale is as much about evidence of capacity as about design.

A Social Infrastructure Assessment pulls the education, health, community and open space strands together, which is worth doing where the authority's contribution requests are likely to be contested. Where they are not, separate short notes are more proportionate.

Deciding what to scope out and how to record it

The judgement that saves money at this scale is not which reports to commission. It is which to leave out, with reasons.

The mechanism depends on whether you are in EIA territory. If you are, a scoping opinion records formally what is in and out, and that is the cleanest protection available. If you are not, the recording has to be done by you, and the place to do it is a scoping note submitted with the application and cross referenced in the planning statement.

A usable scoping note lists each technical topic, states whether it is assessed, and gives the reason where it is not. "No watercourse within 500 metres and the site is wholly in Flood Zone 1, so no flood risk assessment has been prepared" is a reason. Silence is not, and silence is what triggers a validation query.

Then check the authority's own local validation list, because it will contain requirements that no national threshold predicts, and it governs whether your application is registered at all. Browse the full set of report types if you want to sanity check the list against what a large major scheme typically carries.

This is general guidance, not legal advice. Screening thresholds, consultee directions and local validation lists all turn on site specific facts, so check the position with your local planning authority or a qualified professional before relying on it. For specialist technical reports, qualified professional input may be required.

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