Infrastructure Planning Blog

This week we cover a Court of Appeal judgment on environmental assessment and an analysis of one of two solar development consent orders (DCOs) granted this week (the second to follow next week).

HS2 alteration judged unlawful

A judgment relating to High Speed 2 has implications for Rochdale envelope considerations and changes that are not materially new or different from the originally assessed project.

The Court of Appeal reversed a judgment of the High Court on 30 June and declared that putting a section of HS2 into a tunnel instead of on a viaduct did not have deemed planning permission, although it has in fact mostly been built.  The judgment can be found here.  The challenger was North Warwickshire Borough Council, where the relevant section of HS2 was situated.

A tunnel at Bromford in Warwickshire was originally intended to continue on a viaduct but HS2 wanted to lengthen the tunnelled section by nearly three kilometres.  Was this within the scope of the HS2 Act? And if so, did it have the benefit of the deemed planning permission provisions in s20 of the Act?

The Court of Appeal agreed with the High Court on the first question and decided that the change was within the scope of the Act - building the tunnel instead of a viaduct could be characterised as not building the scheduled viaduct work and then relying on the other works powers in section 2(2)(i), which allows the undertaker to 'carry out and maintain such other works, of whatever description, as may be necessary or expedient', and could include the tunnel.  Such works did not have to be ancillary in nature as long as they were for the purposes of the project, namely Phase One of HS2. This is similar to questions that get asked about DCOs and 'drop-in' consents.

However, the Court of Appeal disagreed with the High Court as to whether the tunnel had deemed planning permission and concluded that it did not.  Deemed planning permission for development that is not one of the scheduled works does not apply if, according to section 20(2), (a) it is likely to have significant effects on the environment, (b) is not exempt under the Environmental Impact Assessment Regulations and (c) is not already covered by an environmental assessment for HS2 (all three must apply).  The first two conditions were agreed to apply, the contention was over the third.

The extended tunnel and the new position of the tunnel portal had not been assessed in the Environmental Statement. It was agreed that they would have environmental impacts, 'even if they were no greater than those previously assessed'. The Secretary of State did not explain why he issued a screening decision in March 2021 saying the project was EIA development but then in the subsequent Transport and Works Act Order application decision letter concluded that it did have deemed planning permission (paragraph 14).

The court noted that the effects would be different - although there would be less disturbance at the surface for the length of the tunnel, the portal would be in a different place and there would be more excavated material to dispose of (para 123). The test was not whether if EIA were carried out now, the effects would be no greater than those assessed previously, it is whether the effects had actually been assessed.

As the leading judge (Holgate LJ) says at paragraph 129:  [the] 'interpretation [of relying on part of the project with greater environmental effects already having been assessed] allows the requirement for development consent and EIA to be avoided by the decision-maker comparing the environmental effects of that which has already been approved following EIA during the Bill process with the environmental effects of different works which have not been subject to EIA, including consultation with public bodies, representations by the public and the measures for mitigating those effects.'

It is clear to me that if the original EIA had been flexible enough to have assessed tunnel or viaduct (and probably also different portal locations) then switching from one to the other would not have needed a subsequent EIA - there is a useful analysis of the Tew and Milne cases that led to the Rochdale envelope concept (but did not explicitly refer to it) at paragraphs 131-140 of the judgment. Whether this judgment depends on the specific wording of the 2017 HS2 Act (repeated in the Phase 2a 2021 Act) or has wider implications - or will be claimed to have wider implications - remains to be seen.

Latest solar DCO granted

The Secretary of State for Energy Security and Net Zero granted two solar DCOs on Thursday 2 July, the first time we have worked on two to be granted on the same day.  They are for the Peartree Hill project, an up to 320MW solar farm promoted by RWE Renewables in East Yorkshire and the up to 150MW Dean Moor project promoted by ib Vogt in Cumbria.

The Peartree Hill decision was issued earlier so let's cover that one first and leave Dean Moor until next week.

There's not that much to say about the decision letter in fact. The SoS decided to say more than the Examining Authority on just four issues: need and alternatives (including climate change), biodiversity, land/soil/groundwater and compulsory acquisition/temporary possession.

On need, as is now common to decision letters but applications haven't caught up, the SoS said it was not appropriate to compare a solar farm to an unabated gas power station in terms of the emissions being saved, but rather the current average emissions from power generation in the UK. Nevertheless this ascribed substantial positive weight to the project.

On biodiversity the SoS wanted more information on how the density of skylark territory would be achieved but was satisfied with the answer. On Biodiversity Net Gain the decision letter says 'the Secretary of State agrees with the Applicant and the ExA that it would be unreasonable and unjustified to require the Applicant to secure the BNG mitigation beyond the 40-year lifetime of the Proposed Development', apparently suggested by Yorkshire Wildlife Trust. Well, I'm glad about that, even more than 30 years is longer than will be the case from applications from 2 November.

On Best and Most Versatile agricultural land the SoS asked for more information about it but was satisfied with the result. Finally, an indemnity provision that Northern Powergrid (Yorkshire) didn't like stayed out of the made DCO.

One interesting requirement (16) deals with the interaction with two other solar farms planned for the area, called Field House and Carr Farm, both consented under the Town and Country Planning Act 1990 but not yet built.

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