Originally written 16 October 2015
Unexpectedly wet weather since Wednesday prevented the opening of the new bridge over the A47 at Postwick last night (Thurs-Fri).
Surfacing the new bridge was halted by persistent and sometimes heavy rain on Wednesday. The asphalt surface will not bind to the base layers if they are wet. It had been hoped to catch up yesterday (Thurs 15 Oct), but this was not possible and last night it was decided that it would not be safe to open the new bridge as planned this morning (Fri).
Instead, the old bridge across the A47 was kept open as the route towards Broadland Business Park, Thorpe St Andrew and east Norwich for traffic from the Acle and Great Yarmouth direction, and as the route to Postwick village.
Work on the new bridge will resume as soon as the weather allows. The aim is to open the new bridge, and close the old, overnight tonight (Fri) if possible. Traffic would then start using the new bridge tomorrow morning (Sat). This will only happen if it is safe to do so.
Drivers are asked to pay particular attention to direction signs through the junction during this change-over phase. Norfolk County Council is sorry for last night’s late change of plan, which was for reasons beyond our control and in the interests of road safety.
Further information on the Postwick junction, including the new temporary traffic flows, the safety reasons for the junction layout and final routes for traffic, is available on Norfolk County Council’s website: www.norfolk.gov.uk .
9 October 2015
Drivers are warned that delays are likely around Broadland Business Park and the new Postwick Hub access roads from Friday 16 October 2015 as the A47 Postwick junction improvement shifts into the final phases.
There will also be two overnight closures (see below) to allow traffic management changes to be made and for bridge works.
The latest stage of the project includes the permanent closure of the sub-standard eastbound exit slip-road. This is essential for safety on the 70mph A47 because of a high risk of traffic queuing back down the short slip road on to the dual carriageway. It is not possible to lengthen the slip-road or to reduce this significant risk to road users in any other way (see Notes for Editors).
The changes include the temporary closure of the existing bridge over the A47 for essential maintenance and upgrading. The recently constructed new bridge will come into use (under traffic management) for the first time.
At the start of this new stage of works at Postwick there will be overnight closures of the A47 on Thursday 15 October and Friday 16 October (8pm to no later than 6am). The closures are taking place overnight to avoid peak daytime traffic.
The main impact is on Thursday night for eastbound traffic (towards Acle and Great Yarmouth) when the signed diversion route will be from Trowse, via the A146, A143 and A12, re-joining the A47 at Vauxhall roundabout, Great Yarmouth. Westbound traffic (from Acle and Great Yarmouth) will be able to use the junction slip roads, and on Friday night short diversions for traffic from both directions will be in use.
New Postwick junction traffic flows
The changed routes (see below) for traffic using the Postwick junction will take effect on Friday 16 October.
These alterations to traffic flows are significant and motorists are advised to allow for delays, particularly at peak times and in the period when drivers are getting used to the new arrangements. There is likely to be particular pressure at junctions, such as the Broadland Way/Peachman Way roundabout where temporary traffic lights will be used.
Norfolk County Council is sorry for the disruption that this will inevitably cause and thanks all drivers for their continued patience while these important improvements continue. Completion is expected by mid-December.
Traffic staying on the A47 through the junction will be largely unaffected, although drivers will need to be aware of traffic management changes.
Changes for traffic using the junction
Eastbound (from the Trowse direction) traffic leaving the A47: the old exit slip road will be closed. Instead, vehicles will be directed up the new slip road to the new roundabout. From there, traffic heading into Thorpe St Andrew and Broadland Business Park will be directed around the new link roads. Traffic for Postwick village and park and ride will use the new bridge.
Vehicles from the A1042 Yarmouth Road from Thorpe St Andrew and Norwich will have to go around the new link roads to reach the bridge. Please note: there will be no right turn after crossing the new bridge, so traffic intending to go west along the A47 will be directed to loop around the Oaks lane roundabout.
Westbound (from the Acle and Great Yarmouth direction), traffic leaving the A47 heading towards Broadland Business Park, Thorpe St Andrew and Norwich will be directed across the new bridge and around the new link roads. This route goes through the junction at the southern end of the new bridge, where traffic lights will be installed before completion in December 2015.
Park and Ride. Postwick Park and Ride will continue running, but may be subject to route and timetable changes. Please check with the operator, Konectbus, or go to www.norwichparkandride.co.uk .
The improvement of the A47 Postwick junction, at the eastern end of Norwich Southern Bypass, is essential to business and housing growth in the area. Permissions already exist that would create around 5,000 jobs and 1,600 new homes in the area – but the Highways Agency (now Highways England) put a brake on development because of the lack of capacity at the junction (see Notes for Editors).
In addition to the job and housing benefits in the immediate area, the new junction includes connection to the A47 for the now approved Norwich Northern Distributor Road, which will unlock around £1billion in economic benefits for Norfolk.
Notes for Editors
Diversion routes. Please note that signed diversion routes have to be suitable for all types of vehicle and must therefore be of a similar standard to the road that is being closed.
Postwick Junction website page: www.norfolk.gov.uk/postwick.
Postwick junction improvement: Frequently Asked Questions
Why does the existing slip road off the eastbound A47 have to be closed?
One of the main problems with the old junction is this below-standard slip-road. It takes eastbound traffic off the A47 towards Broadland Business Park and other expanding business areas in and around Thorpe St Andrew, but it is too short and increased use of the junction would further increase the risk of traffic queuing back on to the A47 at peak times. This would cause a very serious hazard to high speed traffic on the 70mph dual carriageway.
The closure of the existing slip road and alternative options were considered in some detail by the Inspector during the public inquiry held in 2013. Since then, approval has also been given to Norwich Northern Distributor Road, underlining the need to improve junction capacity.
Why not simply extend the existing slip road, providing more capacity in that way?
Extending the existing slip road back along the A47 towards Trowse is not viable because it is too close to the bridge carrying the A47 over the river and railway. Ways of retaining the original eastbound slip road were considered at the 2013 public inquiry into the junction improvement, but were ruled out.
The old junction seemed to be coping, so did it really need to be changed?
The old junction was suffering from significant peak time traffic queues and delays on the westbound exit slip road. Trying to resolve this issue placed pressure on the existing eastbound exit slip road (discussed above). It was also only functioning adequately because the Highways Agency put a brake on any further housing and business park expansion in the area. Permissions already exist that would create around 5,000 jobs and 1,600 new homes, but the junction has to be improved first.
Why does traffic have to follow a longer route?
The layout is the only one that provides the increase in capacity while meeting national design standards. The scope for different layouts is severely limited by the nearby A47 bridge over the River Yare, the railway line, a high pressure gas main, land topography, the current road layout and the existing bridge over the A47.
Were any other layouts tried?
Over a dozen designs and a range of variants were looked at, but only the current layout could provide the increase in capacity and meet national design standards. This was confirmed at the public inquiry in 2013, when other options put forward by objectors were looked at but were rejected. The Inspector at the inquiry, having considered all options, was satisfied that the proposed solution is the only viable option.