Draft A27 Chichester Bypass Mitigation Supplementary Planning Document (SPD) Version 2 - May 2024
2.0 Background
(8)The need for A27 Chichester Bypass improvements
2.1 The A27 is part of the Strategic Road Network and is therefore the responsibility of National Highways. Other roads within the District are the responsibility of West Sussex County Council (WSCC). Road congestion is a major concern for residents and businesses in the District; in particular, congestion around the junctions of the A27 Chichester Bypass. This in turn, leads to congestion on the local road network as drivers seek alternative routes, leading to further traffic-related problems on those alternative routes.
2.2 The Local Plan (2014 – 2029) acknowledges that without mitigation, new housing and employment proposed in the Local Plan would increase this congestion further, leading to increased queuing times around the A27 junctions and within Chichester city and a deterioration in highway safety. In response, Policy 8 (Transport and Accessibility) made provision for a coordinated package of improvements to junctions on the A27 Chichester Bypass that will increase road capacity, reduce traffic congestion, improve safety, and improve access to Chichester city from surrounding areas.
2.3 The basis for securing funding for A27 improvements to address the impact of the planned development identified over the plan period is set out in Policy 9 (Development and Infrastructure Provision). This explains that the Infrastructure Delivery Plan will be used to identify the timing, type and number of infrastructure requirements to support the objectives and policies of the Local Plan as well as the main funding mechanisms and lead agencies responsible for their delivery. Further, Policy 9 requires that all development, where appropriate, mitigates the impact of the development on existing infrastructure, facilities or services.
(7)Funding collected or secured to April 2024
2.4 At the time the Local Plan was adopted, the relevant evidence base included the Transport Study of Strategic Development Options and Sustainable Transport Measures (2013) which identified an indicative package of measures for the six junctions on the Bypass, costing £12.82 million. These measures were identified as being sufficient to mitigate the impact of development provided for by the Local Plan. On this basis, the 2016 Planning Obligations & Affordable Housing SPD referred to the objective of securing £11.17 million in development contributions over the lifetime of the Local Plan. The remainder of the identified funding had already been secured by the time the 2016 SPD was adopted, specifically for the identified improvement works to Portfield Roundabout and Oving Road junction. Both of these junction improvements have since been completed.
2.5 Monitoring has indicated that £4.16 million in contributions has been collected since 2016 from development coming forward in the south of the district in accordance with the Policy 9 of the Local Plan and based on the contribution levels set out in the 2016 SPD. In addition, a further £6.16 million has been secured through signed S106 agreements for developments that have yet to commence or where payment triggers are not yet reached. A further £9.22 million in contributions is in the process of being secured (under the contribution levels set out in the 2016 SPD) from the Strategic Development Locations at West of Chichester (Phase 2) and Tangmere, each of which are yet to be granted planning permission. The combined total of these sums was £19.54 million at April 2024.
2.6 Although the Policy 9 of the Local Plan and the 2016 SPD have been successful in securing more than the target level of developer contributions for A27 improvement works, the remaining improvement works to the Fishbourne, Bognor, Stockbridge and Whyke roundabouts have not been possible to deliver. The main reason for this is that the cost of delivering these improvement works has increased very significantly over the past decade, well beyond the level of funding that has been secured through planning contributions set out in the 2016 SPD.
2.7 The Council has continued to press for improvements to the A27 Chichester Bypass to be addressed by central government funding and there has been ongoing engagement between the Council and National Highways over the past decade, seeking to achieve this end. However, in spite of these efforts, no other sources of funding have been made available to address the shortfall from the funding secured through development contributions.
(3)Updated technical evidence
2.8 The Council has updated the cost evidence for delivery of the Jacobs schemes. This has involved an uplift in costs to account for inflation and utilising the WSCC cost estimate model, whilst maintaining the specification of works for the junction improvements as close to the original schemes as possible. Table 1 below sets out the revised cost for each of the required junction improvements yet to be delivered.
Table 1: Updated infrastructure costs
Figures show Pounds in Millions |
Jacobs - Using Revised Costs Lower |
Jacobs - Using Revised Costs Upper |
Fishbourne |
£7.6 |
£10.3 |
Stockbridge |
£8.7 |
£14.6 |
Whyke |
£7.1 |
£13.1 |
Bognor Road |
£9.7 |
£15.2 |
Total for all four junctions |
£33.1 |
£53.2 |
(5)The need for a revised approach
2.9 The evidence supporting the adopted Local Plan concluded that the level of development set out within Policy 4 would give rise to unacceptable adverse traffic and highway safety impacts on the A27 Bypass (and the associated local network), unless it was supported by appropriate mitigation works to improve capacity at the six Bypass junctions. This conclusion is supported by the Council's up-to-date transport evidence [3] which has demonstrated that some of the Bypass junctions are already over-capacity. Therefore, any new dwellings coming forward now, within the south of the District, whether permitted by the Council or on Appeal, place a cumulative impact upon the A27 Bypass, which the proposed junction improvements are seeking to address.
2.10 As set out in Table 1 above, the latest available cost estimates for the remaining junction improvements show an overall cost of between £33.1 and £53.2 million. From this total we deduct the £19.54 million in developer contribution receipts that have already been secured. This leaves a minimum of £13.56 million to be funded through developer contributions secured from the development that comes forward within the remaining period before the new Local Plan is adopted.
(8)The level of development anticipated
2.11 As stated above, the contribution levels set out in this SPD would impact only new residential development that comes forward within the south of the District [4] from now until the adoption of the new Local Plan. The Council's recent transport evidence shows that development within the northern area of the District does not have a significant impact on the A27 Chichester Bypass.
2.12 Planning Permission has yet to be granted for two of the Strategic Development Areas identified in the Local Plan. These are West of Chichester (Phase 2) and Tangmere. However, as these allocation sites both benefit from a 'Resolution to Grant' outline planning permission, their A27 mitigation contributions will be based on the levels set out within the 2016 SPD.
2.13 Taking the above into account, the development that will be affected by the contribution levels set out in this SPD will be in the form of any Parish Housing Sites as well as all 'windfall developments' which are permitted before the new Local Plan is adopted. Based on the Council's monitoring of such development in recent years, it is anticipated that approximately 250 dwellings per year would be affected. It is anticipated that the new Local Plan will be adopted within one year. Therefore, unless the new Local Plan adoption is delayed, the total number of dwellings affected would be in the region of 250.
2.14 As part of the revision to the 2016 SPD, it has been decided that contributions should be sought from all planning permissions where there is a net increase in residential dwellings. This is a change from the 2016 SPD guidance which anticipated that contributions would be sought only from schemes of 50 or more dwellings. The reason for this change is that there is no basis in Policy 9 of the Local Plan to exclude developments smaller than 50 dwellings from being required to mitigate their impact on the A27. Applying the contribution to all new dwellings is fairer and therefore more closely aligns to the 'test' for Planning Obligations set out in Regulation 122(2)(c) of the Community Infrastructure Regulations 2010 (as amended).
[3] Chichester Local Plan Transport Study (Stantec, January 2023)
[4] The 'south of the District' is the area to the south of the boundary with the South Downs National Park, as shown on Figure 1.