|Location Map ( geo)|
|Looking north from the M40|
|Grade separated roundabout|
|M40, A46, A429|
|Junctions related to the A429|
Longbridge Island is junction 15 of the M40.
The modern junction was first built in the 1960s as an egg shaped roundabout with earthworks to enable the A46 to pass over the junction on a flyover at a future date. A single carriageway spur headed east from the roundabout which allows the A41 to bypass Warwick. The junction remained in this form until 1989 even though proposals and orders for the M40 were made soon afterwards.
Within a few years of the junction opening proposals were made to extend the M40 to Birmingham. Unfortunately the existing roundabout wasn't large enough to accommodate the M40 passing beneath it so it was planned to build a new roundabout twice the size. This would retain the egg shape of the present layout. At the same time there was proposals to dual the A46 to Stratford-upon-Avon on a new alignment. This map shows the A46 on this alignment.
Although the three level roundabout was the preferred layout a study was undertaken to explore alternatives. Junctions with freeflow connections between the A46 and M40 were discounted due to cost and complexity so options with an auxiliary roundabout were explored. These alternatives were found to offer no real advantages over the preferred layout and were not as cost effective due to a significantly larger land take. When orders were made for this junction in 1973 it was for a layout similar to the preferred 1970 scheme but with a roundabout more square in shape. The M40 was not built for another 16 years when the first section opened between this junction and the M42 in 1989. By now the layout had changed again so the roundabout had become a perfect circle. For just over a year, the junction formed a temporary terminus for the M40 until the section southwards to Wheatley opened at the start of 1991. Part of the M40 was built on the line of the single carriageway A41.
Construction started in 2008 to create a bypass on the A46, avoiding the main roundabout. The eastern end of the bypass is fully grade separated, while an extra roundabout was created at the western end.
Overnight on 2nd August 2008, the Budbrooke Accommodation Bridge on the A46 to the north of the roundabout was demolished, this allowed construction to continue on the new GSJ to the west of the site.
In October 2009, eastbound traffic on the western side of the junction was diverted onto the new alignment including the new roundabout. Work was underway to remove the old eastbound carriageway to allow the diversion of westbound traffic to the new roundabout.
On the eastern side of the junction, work was nearly complete on constructing the overbridge to take eastbound traffic over the new alignment.
The scheme was fully completed on 18th June 2010.
|Banbury, London||Former route of the A41 Warwick bypass|
|Coventry, Leicester (M69)|
|Stratford||One of only a few sections of the A46 on its original alignment.|
|Warwick||Former route of A46|
|Hampton on the Hill||Terminates on the A4189|
|Banbury||Now forms part of the M40|
- Highways England: Post Opening Project Evaluation - M40 Junction 15 Longbridge Bypass (5 Years After) January 2017 (archive.org)