Camilla Swire, R (on the application of) v Canterbury City Council [2026] EWHC 478 (Admin)

[2026] EWHC 478 (Admin)Case No AC-2025-LON-000697
IN THE HIGH COURT OF JUSTICE
KING'S BENCH DIVISION
PLANNING COURT
Venue Royal Courts of Justice, Strand, London, WC2A 2LLDate 6 March 2026
Before
HER HONOUR JUDGE KAREN WALDEN-SMITH(SITTING AS A JUDGE OF THE HIGH COURT)
Between
THE KINGClaimanton the application of CAMILLA SWIREClaimant
Estelle Dehon KC and Ben Fullbrook (instructed by Richard Buxton Solicitors) for ClaimantMegan Thomas KC and Noémi Byrd (instructed by Canterbury City Council) for DefendantAndrew Tabachnik KC and Gethin Thomas (instructed by Osborne Clarke LLP) for Interested PartyHearing Hearing dates: 13 and 14 January 2026
Approved JudgmentThis judgment was handed down remotely at 10.30am on Friday 6 March by circulation to the parties or their representatives by e-mail and by release to the National Archives.
[1]The Claimant seeks to judicially review the decision of the Defendant, Canterbury City Council (“Canterbury CC”), to give planning permission to Barratt David Wilson Homes Kent (“the Developer”) for the construction of a new eastbound slip road from the A2 and associated development, including the modification of a footpath and cycle route (“the Slip Road Development”) at the location of Wincheap Park and Ride, Ten Perch Road, Canterbury, Kent CT1 3TQ (“Wincheap P&R”). The planning permission provides for:
“a new eastbound (coastbound) A2 off slip, associated reconfiguration of both Ten Perch Road and the Ten Perch Road/A28 junction, modified footpath/cycle routes, ground re-profiling, lighting, surface water attenuation features and landscaping”
[2]Ground 1 of the application for permission to bring judicial review proceedings was withdrawn by the Claimant in her ‘Reply to Defendant’s Factual Update and Response to Reply’ dated 6 May 2025, following the decision of Canterbury CC to approve non-material amendments to the planning permission on 14 April 2025.[3]The application for permission to bring judicial review proceedings had been dismissed on the papers by HHJ Bird, sitting as a Judge of the High Court. The Claimant was granted permission to bring judicial review proceedings on ground 2 at the renewed oral application before Robert Palmer KC, sitting as a Deputy Judge of the High Court, on 18 September 2025.[4]The order granting permission included that Canterbury CC and the Developer should file and serve detailed grounds and provide written evidence within 35 days of the service of the order, which would have been in the last week of October 2025. On 8 December 2025, approximately 5 weeks late, Canterbury CC applied to adduce the statement of Alun Millard, the Principal Transport & Development Planner for Kent County Council (“Kent CC”). I will deal with that application when considering the evidence about transport issues and the consultation response from Kent CC.[5]The Claimant’s case is that Canterbury CC granted planning permission to the Developer for the construction of the new eastbound slip road from the A2 (“the slip road development”) which would result in an “inevitable loss of capacity” for parking at the Wincheap park and ride facility (the “P&R”); and contends that Canterbury CC were obliged, pursuant to the Environmental Impact Assessment (EIA) Regulations, to assess the environmental impact of the development, particularly any impacts on traffic and air quality. The Claimant asserts that Canterbury CC failed lawfully to consider the effects of the slip road development on the P&R, even if temporary, as a likely significant effect of the slip road development; and further failed to consider the effects of the expansion of the P&R as an indirect or cumulative effect of the slip road development and any consequent highways or environmental effects. It is said by the Claimant that Canterbury CC and the Developer’s response is to “seek to walk an impossible line between two contradictory submissions” by saying that the loss of capacity need not be considered because the Planning Committee were entitled to be satisfied that the expansion would be delivered, but also that they were not required to assess the effects of park and ride expansion or provide that information to the Planning Committee because the solution for the re-provision and/or expansion of parking spaces was not known, could not be known, and did not need to be known, in order to reach a rational decision as a matter of planning judgment (see paragraph 53 of Canterbury CC’s detailed grounds of resistance).[6]The position of Canterbury CC, in summary, is that while the slip road development will have an impact on the P&R, both Kent CC, as the local highway authority, and Canterbury CC, as the planning authority, were acting rationally and within the range of reasonable decisions that:(i) the P&R would be expanded to re-provide the parking spaces which would be lost with the slip road development (in light of the provisions of the Local Plan and the £1.1 million plus section 106 payment);(ii) the traffic impacts of any temporary reduction would not lead to significant effects on the environment, it being possible that the expansion could occur before completion of the slip road development; and(iii) without a “worked-up” scheme for expansion of the Wincheap P&R Canterbury could not have carried out an assessment.[7]The Developer’s position, in summary, is to support that of Canterbury CC by saying that there was no demonstrable flaw in the reasoning of Canterbury CC and that Canterbury CC made a series of unimpeachable rational decisions both with respect to the EIA screening opinion and the granting of planning permission.[8]Both Canterbury CC and the Developer rely upon the “backstop” provided by the process prescribed by section 278 of the Highways Act 1980. It is their contention, disputed by the Claimant, that Canterbury CC were entitled rationally to conclude that Kent CC and/or National Highways (NH) would not enter into the necessary section 278 agreements for the slip road development unless they were satisfied that there would not be any unacceptable adverse impacts on the road networks. Canterbury CC relied on the background fact that Highways England (now NH) had refused to progress a section 278 agreement relating to the slip road scheme that had been given permission granted in 2018 on the grounds that NH were not satisfied with safety/design aspects of the proposal.

Factual background

[9]The Claimant is a local resident in Kent. It is set out in her skeleton argument that she has brought this judicial review challenge as she is concerned that planning applications in the local area are properly and lawfully scrutinised. She objected to the slip road development and says that in this judicial review she is supported by those concerned about the possible pressure for expansion of the P&R onto adjacent water meadows, together with concerned Wincheap residents and cyclists. 2016 Outline Permission[10]Canterbury CC granted outline planning permission on 13 July 2016 for a mixed-use development, including for 750 residential units in a mix of sizes, types and tenures, and including a primary school and a nursing home, and formal and informal open space. The planning permission also provided for traffic infrastructure including the slip road development and a condition that: No more than 449 dwellings shall be occupied on the site until A2/A28 Coastbound off-slip at Wincheap, Canterbury…has been completed and is open to vehicular traffic Slip Road Development Permission 2018 Permission

Slip Road Development Permission

[11]Permission for a new slip road to be constructed from the A2 had been granted by Canterbury CC on 9 May 2018. The design was rejected by Highways England (now NH) for safety reasons and required redesign so the section 278 agreement was not entered into. Reliance is placed upon this earlier permission being granted at time when the P&R expansion had not been settled. The OR relating to the 2018 slip road development had made it clear to the Planning Committee that “the application site includes part of the existing park and ride. The reconfiguration and extension of the P&R will be the subject of a separate application to be made by the City Council.” It was also set out that together with the P&R expansion and a new relief road route through the Wincheap commercial estate both the slip road and the re-modelled Ten Perch Road will become part of the wider Wincheap traffic scheme. The P&R expansion and the sliproad were designed to be compatible. Slip road development[12]The construction of the new slip road from the A2 is intended to improve traffic congestion in Canterbury, as cars leaving the A2 for Wincheap would no longer need to leave at an earlier exit and then make their way around the Canterbury inner ring road. Paragraph 4.52 of the Canterbury District Local Plan, Adopted July 2017 (“the Local Plan”), provides that: The Council as majority landowner will look to promote the improvement of Wincheap itself through the re-development of the existing estate, and highway improvements in particular. Part of the S.106 agreement for planning permission CA/15/01479/OUT includes, amongst other items, the provisions of an east bound slip road off the A2. The east bound A2 slip being the major highways infrastructure requirement necessary to support the comprehensive development of the Wincheap Retail Area. The line of proposed new road infrastructure to relieve Wincheap of the in-bound traffic is safeguarded on the Proposals Map.

Park and ride

[13]Under the heading “Wincheap Park and Ride” the Local Plan at paragraph 5.40 sets out that: The regeneration of Wincheap Industrial Estate will require the delivery of a new eastbound A2 off-slip at Wincheap, making the Wincheap park and ride site more attractive for motorists approaching the city from the A2 north-western direction. Therefore, this plan proposes to expand the existing park and ride site at Wincheap. Policy T5 is with respect to the Wincheap Park and Ride and states that “Land identified on the Proposals Map adjacent to the existing Park and Ride site at Wincheap is safeguarded for the expansion of that facility.”[14]The Local Plan further identifies Wincheap industrial estate as the most suitable location for meeting retail capacity for the City over the plan period and that the A28 Wincheap corridor is a primary route into the City which suffers from congestion and pollution. The key transport infrastructure required in the Wincheap area during the plan period includes the new eastbound A2 off-slip road and the re-provision and expansion of the park and ride to capture A2 and A28 traffic (see paragraph 5.48). Policy T11 of the Wincheap Traffic Management Scheme provides: The Council will seek to implement the A2 off-slip road at Wincheap, an A28 relief road through the industrial estate and improvements at Wincheap Green. Any development proposals that might prejudice these improvements will be resisted. Contributions towards these infrastructure improvements will be sought from appropriate developments.[15]Further, Canterbury CC’s District Transport Strategy 2014-2031 (adopted on 13 July 2017), as set out in the Developer’s Detailed Grounds of Resistance set out that: Wincheap Park and Ride 6.31 The existing site is constrained by the River Stour and the A2 and significant expansion is not readily achievable although a limited expansion in the allotments could be feasible. The proposed A2 off-slip from the London direction will cut through the current facility, meaning that a complete rearrangement of parking provision will be required. In addition, the need to increase capacity so that the site can cater for the majority of traffic from the A2 north-western approach will be necessary. Options to provide this additional capacity will include multi-storey facilities and using land behind existing retail units adjacent to the river.

Wincheap Park and Ride

[16]The Local Plan sets out in paragraphs 5.37 through to 5.39 that the role of the park and ride is to provide a less environmentally damaging alternative to the private car and that the Canterbury Parking Strategy states that all future parking demand for the City will be met by expanding park and ride provision. As part of the strategy, the park and ride provision was to be expanded over three park and ride facilities, including Wincheap, where all three were to be expanded so as to create an additional 800 spaces with Wincheap expanding 300 spaces from approximately 600 spaces to 900 spaces.[17]The Local Plan further provides that the precise number of spaces and the split between the three sites will be determined at the appropriate time when development and infrastructure is delivered through the Local Plan period. The Local Plan also provides that the need for park and ride provision will be kept under regular review.[18]On 16 October 2019 Canterbury CC granted planning permission for an extension to Wincheap P&R to provide an additional 228 parking spaces which had been designed to be compatible with the 2018 slip road development. The P&R permission involved the loss of, inter alia, an area of allotments and a large area of field or water meadow to the north of Wincheap P&R, bordering the Great River Stour. This permission was subject to a claim for judicial review by the local branch of the Campaign to Protect Rural England (CPRE) alleging failures of Environmental Impact and Habitats Regulations Assessments. Canterbury CC consented to the quashing of this permission to extend the P&R at Wincheap. There was no consent to the judicial review challenge that had been brought against the P&R extension. It was agreed that in light of the advice from Highway’s England that the future re-design and implementation of the slip road could be prejudiced and so Canterbury CC announced it would not seek to implement the impugned planning permission but “the parties do not agree as to whether the claimant’s grounds would have succeeded at trial, both agree… any trial of those grounds would be academic.”[19]Canterbury CC contend that “it is therefore a matter of fact therefore that there has been a working permission for extending the Wincheap PRF which incorporates part of the field/meadow.” The Claimant contends that is incorrect as the effect of the quashing of the permission, with the consent of Canterbury CC, is that as a matter of law no valid permission had ever been granted (see Lord Diplock in Hoffman La Roche v Secretary of State for Trade and Industry [1975] AC 295, 365G). It cannot be in dispute that the legal effect of the quashing is that the permission had never been validly granted. The point being made by Canterbury is that, as a matter of fact, there had been a working permission for the extension of Wincheap P&R incorporating part of the field/meadow. Application for Permission for Current

Slip road development

[20]The application for planning permission was registered on 16 November 2023. It is agreed that the entirety of the Wincheap P&R and the allotments are within the red line of the area for the scheme for development. The water meadows lie to the north and both the water meadows and the allotments are safeguarded for the expansion of the Wincheap P&R.

Stantec Environmental Impact Assessment Screening Report

[21]The Developer provided an Environmental Impact Assessment (EIA) Screening Report dated June 2023, compiled by Stantec, (“the Stantec report”) which set out that the proposed development of a new A2 coastbound slip road at Wincheap with the associated works, and that “the proposed development will include the removal of the linear woodland adjacent to the A2 and A28 and the southern section of the Park & Ride…”[22]The Stantec report gave consideration to cumulative effects pursuant to the provisions of Schedule 4 of the EIA regulations and cited the PPG, echoing the EIA Regulations, that:
“each application (or request for a screening opinion) should be considered on its own merits. There are occasions where other existing or approved development may be relevant in determining whether significant effects are likely as a consequence of a development. The local planning authorities should always have regard to the possible cumulative effects arising from any existing or approved development.”
Stantec set out that there were two potential cumulative developments had been identified which were either “existing or approved”. These were expanded upon in part 12 of the table included in paragraph 3.12 and can be summarised as the potential for cumulative construction effects in terms of an increase in traffic, emissions and noise from the cumulative developments, “but these are not considered to be significant”; that the effects would be minimised by best practice mitigation measures; that the effects would not be different in nature or complexity and would be integrated into the existing highway network.[23]Part 3 of the table included in paragraph 3.12 of the Stantec report refers to pollution and nuisance and notes that as the proposed development comprises highway infrastructure, “operational emissions would be associated with the number of vehicles utilising the proposed development. However, given the scale of the proposed development emissions would be expected to be minimal, and would not arise [sic.] of the proposed development itself.”

Canterbury EIA Screening Opinion

[24]Canterbury CC undertook its own EIA screening opinion, dated 27 June 2018, pursuant to the provisions of Regulation 6(1) of Part 2 of the Town and Country Planning (Environmental Impact Assessment) Regulations 2017 (“the EIA Regulations 2017”). The request was for a EIA screening opinion “for the proposed construction of a fourth arm slip road, the associated reconfiguration of Ten Perch Road and the Ten Perch Road/A28 junction, modification of a footpath and cycle route, and works to existing surface water drainage, lighting and landscaping.” The assessment was that:
“… the development would not have a regional or national significance that would require referral to the Secretary of State. However, the rights of the Secretary of State to undertake a screening direction remain unaffected should they decide to exercise such powers.”
Further:
“In this instance, the Local Planning Authority is of the opinion that an EIA will not be required to be undertaken for the proposal as it is considered that it would not constitute EIA development.”
[25]The consultees did not advocate for an EIA, although Kent CC, as the local highway authority, did note that a transport assessment (TA) will be required to accompany any planning application in order to assess the impact of the proposals on the highway network, and that Kent CC should agree the scope of the TA in advance. Canterbury CCtransport did not require an EIA from a sustainable transport perspective.[26]The opinion set out the size of the site covering 3.95 ha, comprising existing highways infrastructure, the Wincheap P&R and some undeveloped land to the north west of the P&R site – being the allotments and flood attenuation (or the water meadows). It notes that much of the existing re-modelling takes place over the position and general alignment of existing highway infrastructure and the park and ride site and that “the majority of the works are contained on or between existing highway or developed land.” The slip road is approximately 950m in length and therefore falls below the indicative criteria of 2km. Under the heading “cumulation with other existing development and/or approved development”, the screening opinion sets out that the works are proposed as mitigation in support of the delivery of approved strategic sites and as part of Canterbury’s overall sustainable transport strategy. It was not considered that the relationship between the highways works and associated residential development “in of itself results in significant cumulative impacts. This proposal is for supporting highway infrastructure rather than new built residential or commercial development.”[27]The loss of spaces at the Wincheap P&R was therefore appropriately recognised in the screening opinion. The screening opinion did note that if the timing of the slip road construction, or the extent of the works, impacted on park and ride capacity then the applicant would be required to demonstrate that this would not adversely affect the City’s sustainable transport strategy, lead to additional unacceptable congestion or adverse air quality impacts, or put forward associated mitigation.[28]Under “pollution and nuisances” the screening opinion set out that impacts on traffic and the transportation network, as well as the impacts of any associated lighting, would be fully considered at application stage and that Kent did not advise the need for an EIA assessment at this stage but a Transport Impact Assessment would be required at full application stage. An Air Quality Assessment would also be required.[29]The screening opinion recorded that as the slip road was approximately 950m in length it falls below the indicative criteria set out in the NPPG of 2 kilometres and that given the context of the site, the slip road and associated highway works would not represent a degree of change in the character or scale of the existing highway infrastructure that would be likely to lead to significant environmental effects.[30]Consideration was also given to the “risk of major accidents and/or disasters relevant to the development concerned, including those caused by climate change.” The conclusion was that within the context of the existing highway and car parking setting it was not considered that the works will lead to such significant effects that require an EIA. That conclusion was reached against the backdrop that the proposal might facilitate additional traffic movements through the site and wider area by either diverting traffic to the new junction from elsewhere or generating new trips.[31]The screening opinion concluded that Canterbury CC, as the local planning authority, considered that the proposed development would not have significant effects on the environment and was not EIA development within the EIA Regulations.[32]The types and characteristics of the potential impact set out in schedule 3(3) (a-h) and regulations 4(2) of the EIA regulations were set out and it was noted that neither Kent nor Highways England, now NH, had indicated that significant environmental impacts would be likely to arise. Canterbury CC found that:
“Given the scale, nature and function of the development, localised impacts will be considered and assessed through the regular application process.”
The final conclusion was that the Local Planning Authority considers that the proposed development would not have significant effects on the environment and, as such, the LPA concluded that the proposed development under the Town and Country Planning (Environmental Impact Assessment) Regulations 2017 so that an EIA assessment was not required.[33]The screening opinion concluded that the character, location and impacts of the proposed development were such that an EIA was not required under the regulations. Its conclusion was not limited to visual impact and, as is set out above, the impact of the loss of P&R capacity was considered and taken into account in the conclusions reached.[34]The Canterbury CC EIA screening opinion did not assume the loss of capacity at the P&R was inevitable. It set out that environmental effects would need to be assessed if the timing of the construction or the extent of the works had an impact upon capacity. Kent had not identified any significant impacts at this stage or that it was an EIA development. The transport assessment was something that would be required for the application stage and, similarly, with respect to pollution and nuisances, “Impacts on traffic and the transportation network, as well as the impacts of any associated lighting, would be fully considered at application stage.” It was stated that an Air Quality Assessment would also be required. Consideration was given in the screening opinion to the possibility that the proposal may lead to additional traffic movements and that the transport assessment would need to assess traffic flow and queuing in the following terms:
“The proposals may facilitate additional traffic movements through the site and wider area by either diverting traffic to the new junction from elsewhere, or generating new trips. Within the context of their existing highway and car parking setting, it is not considered that the works will lead to such significant effects that require an EIA. Nevertheless, it will be necessary for any accompanying transport/highways assessment to demonstrate that traffic flow levels and queuing at both the A28 junction and park and ride access are minimised in order to avoid any unnecessary additional impacts, and to reduce the risk of traffic pollution. You would need to ensure that the scope of any assessments consider the Wincheap corridor as a whole.”
[35]The EIA Screening Opinion made clear that an EIA was considered unnecessary in relation to transport and air quality matters, and that environmental effects would be necessary to consider if timing or extent of the works had an impact but no significant impacts had been identified by Kent CC at that stage. It is clear that Kent CC will be fully cognisant of its own road network and the impacts on levels of traffic, for example from peak hour use or different use at different times of the year. Canterbury CC was, as it is entitled to, making a judgment based upon the information received and Canterbury CC was entitled to conclude that any level of disruption would not be to the extent of being significant so as to be to the level of requiring an EIA. It was, in my judgment, a perfectly rational conclusion made by Canterbury CC, as is set out in the screening report, for the issues to be dealt with in the standard planning process. Neither Kent, nor NH, indicated that significant environmental impacts would be likely to arise and the conclusion of the Screening Opinion was that there were no likely significant environmental effects engaging EIA.

Stantec Transport Assessment

[36]The application for planning permission was accompanied, as was highlighted as needed in the screening opinion, by a transport assessment dated October 2023 compiled by the Developer’s agent Stantec. The assessment set out that the background was that Canterbury had been exploring opportunities to increase the connectivity of the A2 to radial routes to the south-west of the city centre for many years (as reflected in the adopted local plans) and that the purpose of the assessment was to “consider the effect of the slip road on the Wincheap series of signals and in the context of the committed development at Thanington Park and Cockering Farm, which now have planning permission.”[37]The Developer’s traffic assessment explains the need for the Slip Road and represented that the Slip Road would improve the operation of the local highway network, in particular by taking traffic off the inner Canterbury ring road and that “… the provision of the proposed slip road would contribute to the overall better management of the roads in the vicinity of the city centre, and should create a greater permeability of routes into and out of the city.”[38]Two scenarios were set out: a 2031 baseline assuming no slip road but including 449 residential units at Thanington Park prior to the slip road becoming available and full development at Cockering Farm, and a 2031 baseline plus slip road, which allowed for an assessment of the effect of the slip road in isolation from development build out. An 8% growth factor was applied to the strategic through traffic on the A28 corridor and traffic interchanging between the A28 corridor and A2 corridor using the A2 slips as highway officers had suggested that they would like to understand the performance of the local road network where some background traffic growth occurs (paragraphs 4.3.2 and 4.3.3 of the traffic assessment).[39]In addition to that background growth, the traffic assessment added committed development for the purpose of the baseline assessment. This committed development was said to be including the Thanington Park Development, where 449 occupied units are permitted prior to opening of the proposed slip road; the Cockering Farm development has permission and can be built and occupied prior to the opening of the slip road; and the P&R expansion at Wincheap has been assumed as was the case within the Thanington Park Transport Assessment. The assessment made it clear (see paragraph 4.5.1) that the committed development (including P&R expansion at Wincheap) had been applied to the 2031 background traffic flows to produce the baseline traffic flows and that the expansion of the Wincheap P&R was assumed “as was the case with the Thanington Park Transport Assessment.”

Kent CC

[40]Canterbury CC point out that Kent CC did not query that assumption but did ask for more information about the number of parking spaces that would be lost in its letter of 25 January 2024 saying as follows:
“The planning application for the proposed development has been submitted following engagement between the applicant’s highway consultant and Kent County Council to provide pre-application advice… The current submission does follow the advice that was provided … It is also appreciated that the application is submitted following the granting of planning consent to a previous configuration of the proposed new southbound off-slip from the A2 into Ten Perch Road at Wincheap under application reference CA/18/00235, which ultimately could not be progressed due to difficulties identified at the detailed technical approval stage with National Highways in respect of compliance with design standards. The requirement for providing the slip road at Wincheap remains adopted policy within the current Local Plan, Transport Strategy and is a planning obligation upon the developer . The current application now seeks to resolve the technical design issues that prevented construction of the earlier scheme that was given planning consent in 2018, and is supported by a new planning consent… The Transport Assessment has modelled the performance of the local highway network under the same assessment criteria as before, which is considered to be the appropriate method in planning terms under the current adopted policies and committed development, and in order to be consistent with the previously agreed approach and assumptions… … … the provision of the slip road from the A2 is expected to provide an overall betterment to the operation of the local highway network covered by the TRANSYT model. In addition it will materially reduce the volume of traffic entering Canterbury from Harbledow, and decrease flows on the ring road too.”
Under the heading “Park and Ride” Kent CC set out that similar to the previously consented scheme, the provision of the slip road will reduce the size of the existing P&R at Wincheap “however it is not clear how many more spaces will be lost in comparison to before and whether the remaining area will be able to accommodate the demand in the event that the site is not expanded. No details have been provided in this regard to quantify the loss of parking spaces proposed or assess the current and future demand generated by the park and ride in order to consider the capacity. Evidence is required to show the current usage and future demand –Action required.”[41]Stantec on behalf of the Developer responded on 26 July 2024 to Canterbury CC, setting out the argument that the provision of a slip road is a requirement of the planning consent for the Thanington Park development and is an adopted Local Plan commitment. It was also stated that the proposal follows a previous consent for the same development, albeit with a slightly amended arrangement to address modern design and safety requirements and, consequently – it was submitted by Stantec – the proposed development should be accepted. With respect to the Kent CC concerns, Stantec set out that the application for a new slip road would have an impact on the existing park and ride facilities:
“This is inevitable given its location and lack of space outside the Park and Ride to accommodate it. The arrangement of the new park and ride facility will be subject to discussion once the design of the slip road is agreed. As KCC recognise, the previous consent also led to the reduction in Park and Ride. We have reviewed the current proposals against that previously consented by the Council and note these will have no greater impact than that previously considered (see Sketch A and Sketch B appended, for information purposes only). Further, as part of the legal agreement for the Thanington Park scheme, a significant contribution has been made towards improvements to park and ride facilities to mitigate this impact. As such, it is considered no further work should be required at this stage in respect of the impact on the existing Park and Ride facility.”
[42]Sketch A provides figures for the previous approved application that the existing P&R spaces are 592 with the lost spaces being 243, with number of parking spaces remaining as 349. Sketch B provides figures for the current application with the existing P&R spaces of 592 being reduced by 216, thereby leaving 376 spaces. The contention on behalf of Canterbury CC and the Developer is that while it is accepted that the proposed development will lead to a reduction in the number of P&R spaces available the number of remaining available spaces would be greater with this proposal than the number of remaining available spaces with the earlier proposed scheme, which had been approved by Canterbury CC on 9 May 2018. While the earlier proposal was ultimately rejected by Highways England (now NH) for safety reasons (so that the section 278 agreement was not entered into and the development could not proceed), the permission thereby being a legal nullity, Canterbury CC and the Developer contend that the principle holds good that if the earlier proposal was approved with more parking spaces to be lost then it cannot be irrational to approve this proposal.[43]Kent wrote to Canterbury CC on 16 September 2024. With respect to the Park and Ride Capacity, the letter refers to the two sketches A and B and the comparison between the amount of parking spaces removed as a result of the previously consented to planning approval layout and what would be removed as a result of the current planning application:
“The drawings detail that the current planning application would result in the loss of 27 less parking spaces than the previously consented scheme, which therefore represents a reduced impact on the Park and Ride site from what the City Council [Canterbury] had already accepted. In addition, it is appreciated that the planning obligations secured through the overarching planning consent at Thaningon, CA/15/01479, requires the applicant to make a financial contribution for the City Council to improve Park and Ride facilities. KCC is therefore satisfied that this action has been addressed.”
[44]Kent CC were therefore satisfied, as the highways authority, that the current scheme would have a reduced impact on the P&R than the previously consented scheme, and were satisfied with the financial contribution being made by the Developer to improve the P&R facilities. The consultation response of Kent CC was obviously an important part of the process for Canterbury CC.

Late Statement of Mr Millard

[45]Canterbury CC provided a statement from a Mr Alun Millard, Principal Transport and Development Planner employed by Kent CC. This statement is dated 8 December 2025 and is provided late, after the date provided in the order of Robert Palmer KC made on 19 September 2025 granting permission to bring the judicial review proceedings. I am satisfied that Canterbury CC acted promptly once they had the statement, although it is clear that the statement was provided with involvement and it may well be that Canterbury CC were concerned that there was some evidence that they were missing to make out their case. The concern that there is with late service of evidence such as this is that the Claimant does not have opportunity to respond, in accordance with the terms of the order. The Claimant in this case did have time to serve rebuttal evidence before the hearing had it been decided that was something she wished to do.[46]Canterbury CC require the permission of the court to rely upon this evidence and the Claimant contends that Canterbury CC should not be entitled to rely upon the statement, not only because it has been provided long after the filing of the Detailed Grounds, but that it is ex post facto evidence that is being used by Canterbury CC to fill an evidential gap, that it conflicts with the evidence contained in contemporaneous records, that it is in breach of the duty of candour, and further that it is irrelevant as it formed no part of Canterbury CC’s decision making process. I am considering the statement de bene esse and, of course, the court is perfectly able to consider the statement but then not take it into account if it is not admitted as evidence.[47]The most significant part of Mr Millard’s 6 paragraph statement, beyond the unsurprising evidence that there were pre-application discussions with the Developer and that the Kent officers had “local knowledge of the application site and surrounding highway network” is the steps taken to assess the use of the P&R. What is said by Mr Millard, and what had not been previously known, is that Kent’s officers carried out “multiple site visits … as well as frequent observation of the Park & Ride’s car park usage displayed live on the City Council’s website. This demonstrated that the existing facility had a significant amount of spare capacity throughout the day.” This led Kent CC to conclude that the spare capacity would be sufficient to account for the proposed loss of parking spaces needed to accommodate the slip road, and any likely overspill if capacity were reached would be minimal and that on the basis of the transport evidence available that “no severe or lasting impacts on the local highway network were anticipated.”[48]The Claimant contends that there is nothing in the statement of how this consideration was fed into the Kent CC decision making process. However, the important point for Canterbury CC was that Kent CC did not consider that the likely impact of the slip road development would be to exceed the severity threshold referenced in the National Planning Policy Framework (NPPF). The statement of Mr Millard explains why Kent came to the conclusion it did, but Canterbury CC were only concerned about Kent CC’s conclusion. There is certainly no breach of candour on the part of Canterbury CC when this information was not within its own knowledge until the statement was provided by Mr Millard (which I am informed was in early December 2025) and Kent are themselves not party to these judicial review proceedings.[49]The reason why a cautious approach must be exercised before exercising discretion to admit evidence that came into existence after the decision under review was made is obvious. Explanatory evidence generated after the decision was made cannot have played any part in the making of the challenged decision. In my judgment, this is an occasion when the court should properly admit the evidence from Mr Millard, as the Principal Transport and Development Planner employed by Kent CC. It is already known that Kent CC were satisfied, as the highways authority, with respect to the impact of the Slip Road on the P&R capacity. The details of the reasons as to why Kent CC were satisfied were not provided in the consultation and Mr Millard has now provided the details of the steps that had been taken by Kent CC. This evidence does not contradict other evidence and it explains, or elucidates, why Kent CC came to the conclusions it did. Insofar as it assists, it supports Canterbury CC’s case that the consultation process, which elicited the response from Kent that it did not object, was rational.[50]As referred to by the Court of Appeal in R (United Trade Action Group Ltd) [2021] EWCA Civ 1197, Green J (as he then was) had set out in Timmins v Gedling Borough Council [2014] EWHC 654 (Admin.) that there “is no black and white rule which indicates whether a court should accept or reject all or part of a witness statement in judicial review proceedings.” There is no fundamental principle to prevent “ex post facto” evidence unless it contradicts the contemporaneous evidence of the decision-making and, if it is provided for the purpose of elucidation rather than for the purpose of fundamental alteration, then it is admissible. The evidence of Mr Millard elucidates the reasons why Kent CC were satisfied and gave the response it did.[51]Mr Millard was not cross-examined (as had been asked for by the Claimant) but there was no need for him to be cross-examined, and that would have been highly unusual in the context of a judicial review. More significantly, while Mr Millard provides elucidatory evidence, the decision of Kent CC is not being challenged and his evidence does not add a great deal. Canterbury CC were relying on the consultation response of Kent CC. There was nothing apparently amiss in that response, it was not contradictory to the overall transport strategy which requires 800 additional P&R spaces over the plan period with the local plan providing that “the precise number of spaces and the split between the three sites will be determined at the appropriate time when the development and infrastructure is delivered through the Local Plan period.” Canterbury CC did not require this elucidation to reach its decision (which is the decision being challenged) and this additional evidence can go no further than provide an explanation as to how Kent CC came to its decision. The Claimant has not put forward contradictory evidence to suggest that the Wincheap P&R is in fact heavily in use and that it is difficult to get a parking space, and that was not something raised in the Planning Committee meeting either by councillors or the members of the public. I do not accept, as has been put by the Claimant, that this evidence bolsters an obvious weakness. It is evidence of limited value, and will be given little weight. While it adds very little to Canterbury CC’s case, and is not determinative of the issues, it helps elucidate why Kent CC came to the conclusion it did. It is clear that Kent CC considered the loss of parking spaces and concluded that the Slip Road Development was acceptable.

The Officer’s Report (OR)

[52]The planning application for the slip road development was made by the Developer on 31 October 2024, registered on 16 November 2023. In describing the proposed development, the OR sets out to the members of the planning committee, amongst other things, that the application site includes part of the existing P&R and that the number of spaces to be removed to facilitate the fourth slip would be 27 fewer than that which was proposed to be removed under the previously approved scheme in 2018:
“11. Members will note that the application site includes part of the existing park and ride. The number of spaces to be removed in order to facilitate the 4th slip under this application would be 27 fewer than that which was proposed to be removed under the previous[ly] scheme for a 4th slip that was approved in 2018. 12. The delivery of the slip road is a requirement of both the Local Plan and the planning permission for the Thanington Park mixed use development which is currently being built out by the application – as approved under CA/15/10479. However, there is a restriction on the number of homes that can be occupied (449) before the 4th slip road is completed. ”
[53]The OR summarised the individual letters of support and objections and recorded that the A2 off-slip is identified as a key priority transport infrastructure project in the Canterbury District Transport Strategy 2014-2031:
“the proposed new off-slip represents part of a wider scheme of key local highways improvements that will positively address local traffic and environmental conditions, as well as support sustainable growth and promote more sustainable patterns of travel”
. Objections, including the “loss of P&R spaces” and “no alternative P&R proposals following quashing of expansion proposals” were included in the OR alongside a summary of points of support, including the anticipated reduction in traffic congestion at Wincheap.[54]The OR refers to policy T11 of the Local Plan providing for the implementation of the Slip Road Development and development of Thanington Park, and that the Thanington development must fund the Slip Road – the delivery of the Slip Road representing “part of a wider scheme of key local highways improvements that will positively address local traffic and environmental conditions…”. Reference is also made in the OR to T17 of the Local Plan which requires the modelling and testing of the “traffic impact of the proposed slip road on the local highway network and strategic road network.”[55]The modelling and testing of the “traffic impact of the proposed slip road on the local highway network and strategic road network” required by policy T17 of the Local Plan was set out in the transport assessment accompanying the application. The OR explained that the Slip Road Development was to principally attract traffic bound for the Wincheap area of Canterbury together with traffic seeking to access the A28 towards Ashford and traffic seeking to access the P&R. As a consequence of the Slip Road Development the volume of traffic entering Canterbury from Harbledown would reduce:
“this flow of traffic is a major contributor to traffic congestion and thus air quality impacts in Wincheap. As a consequence, the slip road is forecast to make a positive contribution.”
[56]Kent CC are reported as having considered the accuracy of the traffic modelling in the transport assessment provided by the Developer and that they considered it an appropriate means to test the impacts of the proposals on the local highway network. Kent CC is reported in the OR as having no objection to the proposals and recommends that the standard construction management plan condition is attached to the consent.[57]NH is reported as being content with planning permission being granted subject to a condition and an informative being added to the permission. The condition is that the development is constructed, subject to the Safety Audit process, in strict accordance with the details set out in the approved drawings and then opened to the travelling public. The reason for that is to ensure that the A2 Trunk Road continues to be an effective part of the national system of routes for through traffic. The informative was that the development could only be undertaken within the scope of a legal Agreement or an Agreements between the Developer and NH and that it is the responsibility of NH to ensure that any necessary agreements under the Highways Act, including section 278 of the Highways Act, are adhered to.[58]Canterbury CC and the Developer submit that Canterbury CC were entitled to rely upon the “backstop” of section 278 of the HA 1980, rationally concluding that Kent CC and the NH would not enter the necessary agreements unless the development satisfied them. There was no reference in the OR to section 278 of the HA 1980 being used as a mechanism to delay the development of the slip road. I will deal with section 278 below.[59]The conclusion of the OR is that the Slip Road Development is a key piece of transport infrastructure identified in the Local Plan and is part of Canterbury CC’s strategy to improve Air Quality in the Wincheap part of the Air Quality Management Area and recommends the grant of permission.

The Planning Committee

[60]The Planning Committee met on 7 January 2025 in order to determine the Slip Road application. The Chairman opened the meeting by explaining that the application was for a fourth slip to the Wincheap roundabout from the A2, the slip road for which permission had been granted in 2018 but did not meet the NH standards as the slip road was too short and the bend was too tight so that it was not considered safe. The loss of P&R spaces formed part of the discussion and there were various queries raised by councillors. Richard Norman, a member of the public, raised the issue as to whether the proposal to develop the slip road would lead to a further application to move the P&R onto Wincheap Water Meadows, albeit he was encouraged that the new Local Plan envisages a new P&R and that there was flexibility for the use of s.106 funding for the P&R. The Chairman set out that it was not possible to give guaranteed assurances but that there were no plans to look at further parking around that site, including the water meadows. He informed the meeting that the section 106 funding was already with the council “We’ve got the money actually. We’ve actually got the funding.” The Planning Committee were therefore reminded that the P&R contribution had been paid.[61]Councillor Buckman set out that one of his bigger concerns was with the park and ride and he was not sure how many P&R places were being lost, which led to his question as to where the P&R should go. His concern was that there might be concreting over green space. An explanation was given by Canterbury CC’s Head of Transport and Environment, Simon Thomas, that Kent CC and NH were content for Canterbury CC to grant planning permission but that they would then have to be satisfied to grant consent under the Highways Act :
“We’re considering it more superficially than Kent County Council and National Highways would.”
[62]Councillor McKenzie asked what would happen to the housing development if permission for the slip road were refused and the planning officer explained that the section 106 agreement attached to the housing development provided that no more than 449 dwellings could be occupied before the road is completed, and that the section 106 agreement was to encourage the developer to build the road.[63]Councillor Prentice raised the impact on the P&R as a concern and wanted to know what the reduction to the P&R spaces there would be and whether there was provision for an expansion of P&R spaces elsewhere. Councillor Bothwell also raised the issue of the impact of the development on the P&R capacity, how would additional parking spaces be provided and would the P&R “go multi-storey”. Councillor Bothwell also raised concerns about the Wincheap Water Meadows. The Chairman responded that the loss of P&R spaces were slightly fewer than the previous application and that there “was no plan to look any further for parking around that site, including on the Water Meadows.” Councillor Old raised concerns that they were being asked to make a decision on very limited information and Councillor Dan Smith raised a concern as to whether the P&R would be moved back onto the water meadows. It was made clear that the replacement of the P&R was not on the application for the development of the slip road, “however it does come under the use of section 106 funds on the Cockering Road one”. It was also explained to the councillors that the slip road had been redesigned as a result of the NH not having been satisfied about the earlier approved plan for the slip road.[64]Paragraph 11 of the OR made it clear that 27 fewer places were to be lost, as compared to the previously approved application. The sketch plans A and B showing the number of parking spaces were not provided in the OR, but it was available information to the Councillors.[65]The Claimant has raised that concerns were raised in that Planning Committee by a member of the public and some of the Councillors. As I have set out above, that is undoubtedly the case but, by reading the transcript of the Planning Committee meeting in full, it is clear that concerns were raised and discussed and responses provided which resulted in eight of the Planning Committee voting in favour of the proposal, three against (Councillors Buckman, N Smith and D Smith) with Councillor Old abstaining. That clearly shows that the concerns were in the main resolved to the Councillors’ satisfaction – including Councillors Prentice, McKenzie and Bothwell. The Planning Committee having resolved to grant permission, this was formally granted by officers under the delegated authority on 22 January 2025.

Legal Framework to the Challenge

[66]Before consideration of the EIA Regulations, it is important to record that Canterbury CC’s decision had to be made in accordance with the development plan and material considerations in accordance with section 70(2) of the TCPA 1990 which included the National Planning Policy Framework (NPPF) as a material consideration (see Suffolk Coastal DC v Hopkins Homes Ltd & Anor [2017] UKSC 37). Paragraph 116 of the NPPF sets out that:
“Development should only be prevented or refused on highways grounds if there would be an unacceptable impact on highway safety, or the residual cumulative impacts on road network, following mitigation, would be severe, taking into account all reasonable future scenarios.”
[67]The potential environmental impacts arise directly as a consequence of the potential highway impacts, namely the potential increase in traffic and/or congestion, and NPPF paragraph 116 is therefore highly relevant.[68]Also relevant are the duties upon Kent CC as the highways authority under section 122 of the Road Traffic Regulation Act 1984 (RTRA 1984) to “exercise the functions conferred on them by this Act (so far as practicable having regard to the matters specified in subsection (2) below) to secure the expeditious, convenient and safe movement of vehicular and other traffic.” Section 2 of the RTRA 1984 gives Kent CC the power to make Traffic Regulation Orders (TROs) including for the preservation or improvement of amenities of the area through which the road runs, which Canterbury CC rely upon as giving Kent the power to mitigate congestion and air quality effects.

Section 278 of the Highways Act 1980

[69]The Developer relies upon the impact of section 278 of the HA 1980, which provides that a highway authority must reach an agreement before any works on a highway may be executed. Section 278(1) provides:
“ A highway authority may, if they are satisfied it will be of benefit to the public, enter into an agreement with any person— (a)for the execution by the authority of any works which the authority are or may be authorised to execute, or (b)for the execution by the authority of such works incorporating particular modifications, additions or features, or at a particular time or in a particular manner, on terms that that person pays the whole or such part of the cost of the works as may be specified in or determined in accordance with the agreement.”
[70]The intention behind section 278(1) of the HA 1980 was set out by Forbes J as follows, as approved by Simon Brown LJ in R v Warwickshire CC, ex p Powergen (1998) P &CR 891:
“… the new section 278 was intended to fit into and play its part in the overall legislative system for the controlled development of land through the planning process and I accept that section 278 must be interpreted accordingly. In my opinion, where the benefit to the public of the proposed highway works, in respect of which an agreement with the highway authority is sought under section 278 of the 1980 Act, has been fully considered and determined in the planning process, because the highway works in question form a detailed and related aspect of the application for development of land in respect of which planning consent has been properly obtained through that planning process, then the highway authority’s discretion whether to enter into the section 278 agreement will necessarily be somewhat limited.”
[73]The highway authority’s statutory discretion under section 278(1) is not unconstrained and “There can be no doubt that ordinarily speaking a highway authority will not be “satisfied it would be of benefit to the public” to enter in a section 278 agreement unless it is satisfied, inter alia, about the road safety implications of the proposed scheme. And until it is thus satisfied, it has no discretion to enter into an agreement.” per Simon Brown LJ in Powergen.[74]Canterbury CC accept that section 278 of the Highways Act 1980 does not empower Kent as the highways authority to prevent the implementation of permission for the Slip Road Development, without a change of circumstance “in such a way which can be reasonably found to undermine the basis of the original decision” (HHJ Russen KC Croft v Devon County Council & Ors [2025] EWHC 881 (Admin.). As Carnwath J (as he then was) put it in R v Cardiff CC ex parte Sears Group Properties Ltd [1988] PLCR 262:
“… where a formal decision has been made on a particular subject matter or issue affecting private rights by a competent public authority, that decision will be regarded as binding on other authorities directly involved, unless and until circumstances change in a way which can be reasonably found to undermine the basis of the original decision. That change may be a change in the factual circumstances or sometimes in the underlying policies affecting the decision.”

EIA Regulations

[75]The Slip Road Development is a schedule 2 development as defined by the EIA Regulations, reg. 3 of the EIA Regulations providing that the relevant planning authority [Secretary of State or an inspector] must not grant planning permission or subsequent consent for EIA development unless an EIA has been carried out in respect of that development. The Claimant’s challenge is that Canterbury CC failed to consider the effects of the Slip Road Development on the P&R and/or any consequent highways or environmental effects in determining that this was not an EIA development and therefore did not require an EIA. The Claimant contends that the approach of Canterbury was irreconcilable with the EIA Regulations and Canterbury CC’s screening opinion.[76]Both Canterbury CC and the Developer rely upon the decision in R(Littlewood) v Bassetlaw DC [2008] EWHC 1812 when Sir Michael Harrison determined that a planning authority was not required to assess the cumulative effects of a proposed development with the potential development of a much larger site when there was no way of knowing what development was proposed or was reasonably foreseeable on the rest of the site:
“There was not any, or any adequate, information upon which a cumulative assessment could be based.”
In Pearce v Secretary of State for Business Energy & Industrial Strategy and Norfolk Vanguard Ltd [2021] EWHC 326, which was concerned with the first of two closely related proposals for offshore windfarms, Holgate J (as he then was) set out that Littlewood did no more than apply the principle that when the EIA Regulations are engaged a decision-maker may not grant planning permission:
“Without, first, being satisfied that he has sufficient information to enable him to evaluate, and weigh the likely significant environmental effects of the proposal (having regard to any constraints on what an applicant could reasonably be required to provide) and secondly, making that evaluation.”
[77]In Littlewood the circumstances were “clearly distinguishable” from Pearce as in Pearce the two projects are closely linked, site selection was based on a strategy of co-location and the second project followed from the first after a relatively short interval.[78]Whether an environmental statement is required pursuant to the provisions of the Town and Country Planning (Environmental Impact Assessment) Regulations 2011 is whether the project is “likely to have significant effects on the environment”: “The decision-maker must have regard to the precautionary principle and to the degree of uncertainty as to the environmental impact at the date of the decision. Depending on the information available, the decision-maker may or may not be able to make a judgment as to the likelihood of significant effects on the environment. There may be cases where the uncertainties are such that a negative decision cannot be taken. Subject to that, proposals for ameliorative or remedial measures may be taken into account by the decision-maker.” (see Pill LJ in R(Loader) v Secretary of State for Communities [2012] EWCA Civ 869)[79]The expression “is likely to have” in the Directive and Regulations means no more than there is “a serious possibility of it happening,” (per Pill LJ in Loader) and Moore-Bick LJ in R(Bateman) v South Cambridgeshire DC and Camgrain Storage Ltd [2011] EWCA Civ 157 referred to it needing “something more than a bare possibility is probably required, though any serious possibility would suffice”. It seems to me that amounts to the same. In order for the development to be likely to have significant effects on the environment there must be more than a bare possibility but a serious possibility of those serious effects. Whether a proposed development is likely to have significant effects on the environment inevitably involves an exercise of evidence-based judgment:
“we are dealing with what is quintessentially a matter of judgment.” (per Laws LJ in Bowen-West v Secretary of State for Communities and Local Government [2012] En LR 448, as cited in Loader. Elias J set out in Hereford Waste Watchers Ltd v Herefordshire Council [2005] EWHC 191, that the decision as to whether a process or activity has significant environmental effects is a matter for the judgment of the planning authority but, in making that judgment, it must have sufficient details of the nature of the development, its impact on the environment and any mitigating measures. It is for the planning authority to determine whether it has sufficient information to enable it to make the relevant judgment and it does not need to have all the available material to be satisfied that it has sufficient to enable a clear decision to be reached: “If the authority is left uncertain as to the effects, so that it is not sure whether they may be significant or not, it should either seek further information from the developer before reaching a conclusion.”
[80]Schedule 3 of the EIA Regulations sets out the characteristics of the development that must be given particular regard to, “which includes cumulation with other existing development and/or approved development.”[81]The Court of Appeal in Loader recognised that the complexities of the EIA process are such that it is not to be applied to all developments:
“A formal and substantial procedure is contemplated, potentially involving considerable time and resources. It is contemplated for a limited range of schedule 2 projects, those which are likely to have significant effects on the environment. To require it to be followed in all cases where the effect would influence the development consent decision would devalue the entire concept.”
[82]The Claimant’s contention is that the Slip Road Development will “inevitably” lead to a requirement for P&R expansion and the expansion was reasonably foreseeable as it is within the local plan. On that basis, it is submitted by the Claimant that some proposals – such as the possibility of Wincheap P&R becoming a multi-storey car park or expansion onto the water meadows – could have been assessed. Canterbury CC and the Developer both dispute the Claimant’s fundamental contention that there could have been any assessment of the non-traffic related environmental effects of any P& R expansion, for example any impact on landscape character, as there was not a worked-up scheme for such expansion.[83]Both Canterbury CC and the Developer accept that there was to be an inevitable impact on the P&R at Wincheap by virtue of the Slip Road Development, but not that there would be an inevitable loss of capacity. The screening opinion provided that environmental effects would need to be assessed if the time of the construction or extent of the works had an impact on P&R capacity and that more information on highway impacts would be required at the planning application stage. Kent CC as the highways authority did not identify any significant traffic impacts or that it was an EIA development. The transport assessment provided with the planning application explained the need for the slip road and assumed that the P&R would be expanded, which was not challenged by Kent.[84]In order to challenge the decision of Canterbury CC not to undertake an EIA Screening Opinion, the Claimant must establish that Canterbury CC came to decision that no council could rationally have come to, and/or that Canterbury CC was irrational in failing to seek further information before reaching its decision that an EIA Screening Opinion was not required before reaching the decision to grant planning permission to the Developer for the slip road development. Any challenge is therefore made on conventional Wednesbury principles and, “in the absence of a direction from the Secretary of State, it is for the local planning authority to determine whether an application is a Sch.2 application… Whether a proposed development is likely to have significant effects on the environment involves an exercise of judgment or opinion. It is not a question of hard fact to which there can only be one possible correct answer in any given case… the role of the court should be limited to one of review on Wednesbury grounds” per Dyson LJ in R (Jones) v Mansfield DC [2003] EWCA Civ 1408.[85]In reaching its decision Canterbury CC was under the Tameside duty to inform itself, through further necessary inquiries, of the information required for its (Secretary of State for Education and Science v Tameside MBC [1977] AC 1014) It is, of course for the decision-maker to determine what inquiries are necessary and the Court of Appeal summarised the principles relating to the Tameside duty in R(Balajigari) v Secretary of State for the Home Department [2019] 1 WLR 4647, approving Haddon-Cave J (as he then was) in R(Plantagenet Alliance Ltd) v Secretary of State for

Justice [2015] 3 All ER 261):

“First, the obligation on the decision-maker is only to take such steps to inform himself as are reasonable. Second, subject to a Wednesbury challenge, it is for the public body and not the court to decide upon the manner and intensity of inquiry to be undertaken… Thirdly, the court should not intervene merely because it considers that further inquiries would have been sensible or desirable. It should only intervene only if no reasonable authority could have been satisfied on the basis of the inquiries made that it possessed the information necessary for its decision. Fourthly, the court should establish what material was before the authority and should only strike down a decision not to make further inquiries if no reasonable authority possessed of that material could suppose that the inquiries they had made were sufficient…”
[86]In challenging the decision of Canterbury CC, the Claimant appears to contend that the planning committee was being misled by the Planning Officer and refers to the guidance provided by Lindblom LJ in R(Mansell) v Tonbridge and Malling BC [2019] PTSR 1452 which is to be applied in consideration of both written and oral advice given:
“ (2) The principles are not complicated. Planning officers’ reports to committee are not to be read with undue rigour, but with reasonable benevolence, and bearing in mind that they are written for councillors with local knowledge…. Unless there is evidence to suggest otherwise, it may reasonably be assumed that, if the members followed the officer’s recommendation they did so on the basis of the advice that he or she gave… The question for the court will always be whether, on a fair reading of the report as a whole, the officer has materially misled the members on a matter bearing upon their decision, and the error has gone uncorrected before the decision was made. Minor or inconsequential errors may be excused. It is only if the advice in the officer’s report is such as to misdirect the members in a material way – so that, but for the flawed advice it was given, the committee’s decision would or might have been different – that the court will be able to conclude that the decision itself was rendered unlawful by that advice.”” (3) Where the line is drawn between the officer’s advice that is significantly or seriously misleading – misleading in a material way – and advice that is misleading but not significantly so will always depend on the context and circumstances in which the advice was given, and on the possible consequences of it. There will be cases in which a planning officer has inadvertently led a committee astray by making some significant error of fact… or has plainly misdirected the members as to the meaning of a relevant policy … There will be others where the officer has simply failed to deal with a matter on which the committee ought to receive explicit advice if the local planning authority is to be seen to have performed its decision-making duties in accordance with the law … But unless there is some distinct and material defect in the officer’s advice, the court will not interfere.”
[87]The oral advice supplements the written advice and is considered in conjunction with that written advice (R(Lisle-Mainwaring) v Kensington & Chelsea RLBC [2024] EWJC 440).[88]Subsequent to the close of both written and oral submissions, the Claimant notified the Administrative Court that it wished to refer to another Court of Appeal decision – R (Ashchurch Rural Parish Council) v Tewksbury Borough Council [2023] PTSR 1377 - but, as a consequence of its late submission, would not be providing any submissions. It is a surprising that this case was being referred to at such a late stage, but I have considered it and do not consider it assists the Claimant in the circumstances of this matter. There are some important principles set out in the case: first, that planning authorities are to apply a balanced approach to material considerations and, when treating prospective benefits of wider development as material factors must also take into account any adverse impact that the development might have; second, that the project may not be circumscribed by the ambit of the specific application; and third, that a project cannot be “salami sliced” to avoid the need for an EIA. None of these principles apply to the facts of this case. This project is not being “salami sliced” to avoid the need for an EIA as it has at all times been common ground between the Claimant, Canterbury CC and the Developer that the Slip Road Development and the P&R expansion are not, and do not fall to be considered as, a “single project”.

Discussion and Conclusions

[89]I reach my conclusions based upon the factual background and legal framework set out above, without repeating the same.[90]It is said by the Claimant that Canterbury CC and the Developer “seek to walk an impossible line between two contradictory submissions” by saying that the loss of capacity need not be considered because the Planning Committee were entitled to be satisfied that the expansion would be delivered, but at the same time that they were not required to assess the effects of park and ride expansion or provide that information to the Planning Committee because the solution for the re-provision and/or expansion of parking spaces was not known, could not be known, and did not need to be known, in order to reach a rational decision as a matter of planning judgment.[91]In my judgment, Canterbury CC and the Developer are not making contradictory submissions. It was entirely rational for the Planning Committee to conclude, on the basis of the information available, that the loss of spaces at the P&R would be mitigated while also saying that this was not a development that required a full EIA.

Evidence before the Planning Committee

[92]The Planning Committee was aware that approval of the Slip Road Development would result in an initial loss of a substantial number of existing spaces. While they were not provided with the precise numbers at the committee meeting they were informed that it was 27 spaces fewer than the spaces that would have been lost had the earlier approved proposal been built. The precise number of spaces lost was within the information available to the Planning Committee, albeit not directly cited at the meeting, no-one said that they could not make a decision without that figure directly before them at the meeting with the one member who said that he did not feel there was sufficient information abstaining in the vote. The Planning Committee were also aware that the Developer had already contributed £1.1 million pursuant to the section 106 agreement entered into for the purpose of mitigation of impacts of the Slip Road Development, and they were informed in the OR that expansion of the P&R was part of the local planning policy as it was contained in both the Local Plan and the District Transport Strategy.[93]The Planning Committee was rationally entitled to conclude on that information that they had sufficient information before them to reach a conclusion as to whether planning permission ought to be granted for the Slip Road Development. It was not irrational for the members of the Planning Committee to not require further information about what precise form the P&R expansion would take in circumstances when Kent CC, as the highways authority, had not raised concerns and were satisfied by the information provided by Stantec on behalf of the Developer.

The Screening Opinion

[94]Contrary to the contentions of the Claimant, in my judgment Canterbury CC reached entirely rational determinations in its screening opinion which led to the decision that the Slip Road Development did not require a full EIA. As is set out above, only a limited range of developments are required to undergo a full EIA process under the regulations and the Slip Road Development is less than half the indicative criteria of 2km as set out in the NPPG for road infrastructure developments requiring the EIA.[95]The Claimant contends that it was already known that there was impact on the P&R capacity which meant that the Developer ought to have been required to demonstrate that the impact on P&R capacity would not adversely affect Canterbury CC’s sustainable transport strategy or lead to additional unacceptable congestion or adverse air quality impacts. This challenge to the decision making process undertaken by Canterbury CC is, in my judgment, not supportable.[96]Canterbury CC determined that the Slip Road Development did not fall within the limited range of developments that require the full process of EIA screening pursuant to the regulations:
“It is considered that the development would not have a regional or national significance that would require referral to the Secretary of State … the rights of the Secretary of State to undertake a screening direction remain unaffected should they decide to exercise such powers.”
Even with a loss of P&R capacity, Canterbury CC was satisfied that significant effects were not likely and, rather than an EIA, determined transport and air quality assessments should be carried out in the context of the planning application. That was a rational decision that Canterbury CC was entitled to come to, having carried out its screening report and in reliance upon the consultation responses, including from Kent CC and NH, which were properly taken into account.[97]The reasons for coming to the conclusion that an EIA screening was not required are set out in the screening opinion. This includes that the length of the new road was considerably below that which would be indicative of a need for an EIA (as referred to above) and that the existing context of the site, the slip road and the associated highway works would not represent a degree of change in the character or scale of the existing highway infrastructure that would be likely to lead to significant environmental effects in either transport or air quality terms such that a full EIA was required. Canterbury CC was entitled to take into account its powers to scrutinise and its ability to rely upon the highway authorities in reaching its conclusions and to judge whether the loss of spaces at the P&R and any non-replacement would result in the Slip Road Development resulting in likely significant environmental impacts in either air or transport terms.[98]In reading the entirety of the screening opinion, it is clear that Canterbury CC was considering all the impacts referred to in the EIA regulations and not simply the visual impacts, stating that “Given the scale, nature and function of the development. Localised impacts will be considered and assessed through the regular applications process” and concluding that “the Local Planning Authority considers that the proposed development would not have significant effects on the environment” and that “the proposed development is not EIA development” in accordance with the EIA regulations so that an EIA is not required.[99]There is no concern raised by Kent CC about the transport assessment. Having requested information about the numbers of P&R spaces that would be lost by the Slip Road Development, the Developer’s agent Stantec provided information which satisfied Kent CC, who did not then make any objection. Kent CC reached a rational judgment that it was entitled to reach and Canterbury were acting rationally in relying on Kent CC’s response to the consultation that the proposal was acceptable.[100]Canterbury CC did not, as has been contended for by the Claimant, need to seek information about the location, scale, form and timing of any future P&R expansion and the potential options of such expansion. The Planning Committee were entitled to take into account that P&R spaces would be replaced without needing to assess an actual scheme and the likely effects of such a scheme. Canterbury CC had the knowledge that Kent CC did not object to the proposal without any actual scheme to assess and Canterbury was not required to take into account potential future P&R expansion schemes, which had not been worked up. There was no requirement for Canterbury CC to require the Developer to carry out any EIA assessment of a range of potential options for the expansion of the P&R. The expansion schemes were not certain in any way and were not capable of assessment but, in any event, Canterbury CC was not relying on expansion of P&R as mitigation for the Slip Road Development as the effects of that development were not considered by Canterbury CC to be either severe or significant[101]The form and nature of any expansion of the P&R could not realistically be ascertained as a consequence of the wide range of potential variables. For example, the expansion could be onto other land, or into multi-storey carparking or a combination of expansion upwards and outwards. In order to assess each potential option there would need to be an assessment of all the potential impacts, such as flooding, air pollution, visual and landscape; and all of those assessments would not be based on anything that had any degree of certainty. It was not realistic for Canterbury CC to embark on the task of assessing all the potential impacts of any potential expansion of the P&R. Cumulative effects of a development are only to be considered so far as it is reasonable to do so. There was no basis for Canterbury CC to undertake a cumulative assessment. Canterbury CC was not required to assess the theoretical possibilities for mitigation options in order to act rationally.[102]The Claimant further contends that Canterbury CC failed to comply with its Tameside duty and that further enquiries ought to have been undertaken by Canterbury with respect to the form of expansion to the Wincheap P&R.[103]I do not find that there was any such failure on the part of Canterbury CC to comply with its Tameside duty in this matter. It was rational for the Planning Committee to conclude that it did not require further information before making its decision on the proposal for the Slip Road Development. The court will only intervene if no reasonable authority could have been satisfied on the basis of the inquiries made that it had sufficient information to make its decision. The Planning Committee were also aware that Kent CC did not express concern, once it had received further information from the Developer, and that Canterbury CC’s transport team were not requiring further information beyond the screening report it had undertaken and the transport assessment.[104]In my judgment, Canterbury CC reached its determination to permit the Slip Road Development on an entirely rational basis and came to an unchallengeable conclusion in its screening opinion that the Slip Road Development did not require an EIA pursuant to the Regulations.

Section 278

[105]Mr Thomas had set out in the discussions at the planning meeting that both NH and KCC were content with the grant of planning permission for the design of the layout of the Slip Road Development “but they will then have to grant consent under the Highways Act for the detailed design, light sequencing and every other aspect that relates to the public highway… We’re considering it more superficially than Kent County Council and National Highways would.” It can properly be said that the planning committee were aware that both NH and Kent CC would be considering the application in detail with respect to detailed design. Mr Thomas put it this way to the committee members making the planning decision:
“I mean this is a bit of an odd one because this is a piece of highway infrastructure, so Kent County Council, the Highways Authority and the National Highways are much, yeah, leading on all of this and they’re having all of the discussions with the applicant, but we’ve got a planning application because it needs planning permission.”
[106]It is correct to say that the planning committee were therefore aware that it was for NH and Kent CC to determine whether the Slip Road Development would proceed on the basis that it was of benefit to the public. However, as is clear from Carnwath J in Sears, interference with the planning permission granted would only be on the basis of there being a change of factual circumstances or in the underlying policies which would undermine the basis of the original decision. There is no reference to section 278 in the OR relating to P&R places, and no suggestion from Kent CC or NH during the consultation process which suggests that section 278 of the HA 1980 would be used to prohibit the Slip Road Development as a consequence of an issue with the P&R places. The Environmental Impact Assessment Screening Report provided by the Developer’s agents, Stantec, did not refer to section 278. Further, in the letter dated 26 July 2024 to Canterbury CC, Stantec referred to the fact that fewer places would be lost than in the earlier scheme for which permission had been granted and the contribution already made towards P&R facilities to mitigate the impact, but did not mention section 278.[107]In my judgment, section 278 of the HA 1980 and any potential impact it might have with respect to the provision of P&R did not feature in the decision making process. It is not, as contended for by the Developer, “self-evident” that the Planning Committee of the Council was well aware that Kent CC and NH would use their section 278 powers in furtherance of public benefit to avoid any adverse impacts from a timing gap in the provision of new P&R spaces. While the 2018 slip road consent was not implemented because NH concluded that the design was unacceptable and therefore refused to progress the section 278 agreement, that was based on safety grounds and at no point was it indicated that section 278 could or would be used to delay implementation of planning permission for the Slip Road Development pending any expansion of P&R. The reference to section 278 in the OR was in relation to refinement of the access arrangements for highway safety.[108]NH were concerned to ensure that there was an informative within the permission which highlighted section 278. However, there is no reference to that being related to the provision of P&R spaces or the potential impact of a shortfall. In my judgment, the reliance on section 278 of the HA 1980 by the Developer, and to a lesser extent Canterbury CC, does not support the defence to the claim brought by the Claimant.[109]However, for the reasons set out in detail above, the challenge does not succeed. Canterbury CC did not fail to take into account matters that it ought to have taken into account and its decision to grant planning permission for the Slip Road Development was made rationally and lawfully. The claim for judicial review is therefore dismissed.