Highways England's reasons for rejecting the two locally proposed schemes:
“Further to our meeting of 13th December with Jim O’Sullivan for Highways England to discuss the work undertaken by Systra and BABA27 group, we write to confirm the discussions and outcome of that meeting.
“The Mitigated Northern Option follows similar alignments to previous routes considered by Highways England but the mitigation included the majority of the road in deeper cutting, the inclusion of green bridges at 2 key locations, desire for noise barriers over greater length and no junction at the A286.
“The tie in with the existing road at the eastern end was slightly further east, this option is at this time considered technically buildable. Part of the new by-pass and a relocated local road (New Road) would intrude into the South Downs National Park (SDNP) and would also impact on Goodwood Estate.
“The intrusion into SDNP is against the National Policy Statement for National Networks (Section 5.150) and therefore with the presence of a viable alternative (all five of the RISl options) the Mitigated Northern Option is highly unlikely to obtain approval through the DCO process.
"The option would also likely require substantial works at the Boxgrove roundabout, probably in the form of grade separation, this work is outside of the original scheme and has not been included in the cost figures below.
“The estimated cost of the Mitigated Northern Option is in excess of £480m.
"The costs also do not include for mitigation of the construction impacts on Goodwood estate operations or events.
“The mitigation enhancements would not increase the scheme benefits and hence the BCR would be greatly reduced from previous options resulting in a scheme that would not offer value for money and therefore the option is not supportable by Highways England as a promotable RIS scheme.
“The mitigated southern option proposed underpasses at Fishbourne and Stockbridge roundabouts, the desire for all turning movements at all existing junctions, with grade separation at Portfield roundabout, as well as enhanced noise and visual mitigation measures.
“The option presented is not technically buildable and some other elements carry challenging construction and ongoing maintenance issues with resultant cost implications.
“The proposal for underpasses at both Fishbourne and Stockbridge roundabouts would incur considerable build and ongoing maintenance costs due to the ground conditions and high water table requiring pumping both during construction and thereafter for the lifetime of the scheme.
“The suggestion of an underpass at Stockbridge roundabout also incurred the costs of diverting the Chichester Canal which would require land take from the Chichester College sports field for the diverted canal.
“The construction period for underpasses would be greater than the previously proposed flyovers with associated traffic disruption.
“For Fishbourne and Stockbridge grade separated junctions to comply with Highway Standards it is not possible to have slip roads facing each other.
“For the costing exercise to make the scheme feasible the cost allowed for the western section of the previous considered Stockbridge link road and no west facing slip roads at Stockbridge.
“At Stockbridge and Whyke junctions, to comply with Highways Standards it is not possible to have slip roads facing each other, and likewise between Whyke and Bognor roundabouts.
“The costed option included for the local road being carried over the A27 at the Whyke junction as in RISI Option 2A.
“The flyover option at Bognor roundabout as per RISl Option 2A is feasible (subject to slip road conflicts with Whyke) and was used for the costing exercise.
“The proposal at Portfield junction for a flyover and all direction slip roads is technically challenging.
“To achieve a suitable alignment at even a reduced speed limit requires a horizontal curve that either passes over (through) the new development on the southern side of the junction or travels over the lake on the northern side for its whole length, both with considerable cost implications.
“The tie in with the existing alignment at the eastern end would also become technically unachievable with the slip roads at Temple bar junction, the mitigation of which has not been detailed or costed.
“There are also technical difficulties in regard the new junctions linked with the Shopwhyke Lakes development, the mitigation of which has not been detailed or costed.
“The Mitigated Southern Option allowed for considerable noise barriers and landscaping, these are limited given the locality of the road in regard residential and commercial development along the various sectiors ofthe by-pass and would be technically challenging and costly.
“Allowing for the difficulties in delivering the suggested mitigations and the costs of difficult construction at Fishbourne, Stockbridge and Portfield this option is costed at £500m.
“The RISI Option 2A was costed in the order of £250m, with the benefits of the mitigated southern Option being little different to the RIS1 option the BCR would be expected to be below 1.5 which does not deliver value for money.
“The HE proposed RlSl scheme was cancelled by the Secretary of State primarily due to the lack of local support for the scheme.
“Whilst the BABA27 work has indicated a level of consensus is possible, the suggestions that they have put forward for both northern and southern options are undeliverable in our opinion due to their costs and in the case of the northern option, the impact of national policy.
“In light of the above it is clear that both presented options, Mitigated Northern and Mitigated southern, have considerable issues to delivery that canaot at this time be overcome.
“This along with the considerable costs without increased benefits mean the scheme would not represent value for money and therefore it is not possible to take a major improvement of the Chichester bypass forward at this time.”
Read more at:
https://www.chichester.co.uk/news/polit ... -1-8767119
