A challenge to a planning permission under Section 288 of the Town and Country Planning Act 1990 may be brought only on normal public law grounds. It is not an opportunity for a reconsideration of the planning merits of the decision made by the planning authority/Secretary of State’s inspector. It’s much concerned with whether a decision was based on a correct understanding of any relevant development plans and of any evidence. But within that context the planning authority/inspector is entitled to reach their own planning judgment.
The court is the final authority as to the interpretation of any relevant policy document but will not interfere with the planning authority/inspector’s planning judgment which is the exclusive province of the planning authority/inspector.
The High Court case of Lord Mayor And Citizens of the City of Westminster v The Secretary of State for Communities And Local Government & Anor  concerned a proposed Sainsbury’s in Greencoat Place, Westminster which the Council had described as “a quiet road” in “a quiet hinterland” with “low ambient noise levels”. However, the figures produced even by the Council entirely failed to back that up.
The court found that the proposed grocery deliveries that the inspector had to consider were just a further series of noisy events in what was already a quite noisy street: especially during the day time, when the street had a considerable number of very loud noise events already.
The inspector’s task had been to evaluate the impact of adding the noise of deliveries to the existing noise in Greencoat Place. In order to do that he had, firstly, to determine how the baseline of existing noise was to be established; then he had to see how he could most appropriately add the extra delivery noise to that base to discover the impact of the proposed development.
In respect of both existing noise and the delivery noise the inspector had a number of measurements available including LAeq.1Hr and LAmax.1Hr, showing the ambient noise averaged over one hour and the maximum noise to be heard in an hour. The data he had included indications as to how many loud noise events there were in the existing situation, and how many loud noise events would be created by delivery.
Sainsbury’s had proposed that the LAeq figures be aggregated across a 12-hour day. That would have given an average ambient noise figure for an entire day but, the inspector noticed it failed to recognise that some hours were quieter than others.
On the other hand the Council wanted to average all the quietest hours, which would have given an indication of the ambient noise in the quietest hour of the day, but failed to recognise that for the rest of the day the ambient noise was louder, so that the impact of a delivery would be less.
Exercising his planning judgement, the inspector had been entitled to conclude that any increase in noise levels is undesirable, but he had to judge whether the proposed increase was unacceptable in what was not the quiet backwater described by the Council, but, already, a noisy city street.
Accordingly the Council’s challenge to the planning permission failed on this ground and, in fact, on a number of other grounds as well.
This blog has been posted out of general interest. It does not replace the need to get bespoke legal advice in individual cases.