In 2005, Norfolk County Council found through consultation and investigation that building a road over the River Wensum Special Area of Conservation (SAC) would be an impossibility due to the significant adverse impact on biodiversity and landscape. The question now arises: what has changed since then to justify the current proposal for constructing a viaduct to facilitate a new road over the same river?
Back then, Natural England stated that western routes with dual carriageway river crossings would have a "very large adverse impact on biodiversity." The Environmental Agency also concurred, agreeing that a new crossing of the River Wensum and its associated infrastructure would have a substantial negative impact on the landscape, which would be difficult to mitigate.
Furthermore, evidence from Norfolk County Council's external consultants, Mott MacDonalds, and the County Council's Environmental Coordinator suggested that any road scheme requiring a new or widened bridge crossing over the SAC would adversely affect the site's integrity. Statutory environmental bodies backed this opinion.
Mitigation was considered at that time, but it was widely believed that no sufficient or adequate mitigating measures could overcome the adverse effect on the site's integrity.
It was also recorded that the legislation and policies protecting the biodiversity and landscape of the Wensum Valley meant that any new road proposal involving a dual carriageway crossing of the Wensum would likely face a public inquiry. It will be interesting to see whether the same happens if and when the new scheme reaches the planning stage.
If called in it was considered by Leading Counsel engaged by the Council advised that although it could be argued there was an economic and social justification for the scheme, little weight would be attached to relieving congestion in the Norwich area, one of the same stated objectives for the now proposed Norwich Western Link Road.
Furthermore, it was considered a road scheme that included a new crossing of the River Wensum SAC would have a high risk of failure unless the County Council could prove beyond doubt at an Inquiry that the scheme would not negatively impact the site's integrity.
The primary concern during the 2004 consultation was finding the best way to join the A47 west of Norwich with the A1067 Fakenham Road while minimising the impact on the landscape and the Wensum river valley, which is protected under UK and European legislation. One proposed solution was to use the existing bridge on the A1067 at Attlebridge to cross the River Wensum and construct a new single carriageway road around Weston Longville as a link to the A47. An alternative option that could still feature significantly at a future public inquiry.
In light of the proposed Norwich Western Link Road, it's essential to consider what has changed since 2005 that could justify this new approach. If anything the environmental landscape has become even more sensitive due to the finding of a super colony of highly protected bats and the ever decreasing condition of the River. Given this the only reasonable conclusion one can reach is that despite possible technical advances in construction the environmental threshold has become even higher.