During April and May we have carried out bulk earthworks on Stoneleigh Road East which has included compaction trials on both sides of the A46.
During April and May we have carried out bulk earthworks on Stoneleigh Road East which has included compaction trials on both sides of the A46. Topsoil strip activities have been completed in preparation for cut and fill earthworks, primarily around the location of the new southbound offslip road and the west side of the new A46 gyratory.
Tree surgery have been completed in the Beekeepers area near Dalehouse Lane Roundabout in order to gain better access to the works whilst protecting the health of the trees. Also, in this area, work has commenced on constructing the flood compensation area near to Finham Brook.
The satellite compound is now fully established which assists in providing storage areas for material deliveries to site as well as providing welfare facilities for the construction workers nearer to their working areas.
Due to the site’s proximity to Stoneleigh Park ( where a large mass vaccination site has been established ), restrictions on the use of traffic management on the public roads within the site has been in effect. These restrictions are under constant review with both Highways England and Warwickshire County Council in their capacities as Highway Authorities for the A46 and local roads respectively. Some traffic management off-peak has begun to be used on the local road network, where necessary to complete isolated works activities, but this continues to be closely monitored by WCC Network Management.
Traffic Management has been installed on the southbound offslip and northbound onslip to close a single lane on both slips. This is to allow safe working room for the installation of drainage and earthworks when near the existing carriageway and slip roads. This arrangement is expected to be in place for a few months.
Progress to Date
Cut/Fill Earthworks Activity
Bulk earthworks have been undertaken by excavating the area at the bottom of the new southbound Offslip and then transporting it to the area near the new gyratory/roundabout to build up this area. A large amount of the cut activity has been completed in this area and the road box excavation will follow as the next step in the construction of the new slip roads.
Compaction Trials
Prior to the use of any imported or recycled ground material, compaction trials must be undertaken to prove the suitability of the material and the compaction method proposed in constructing the new embankments. Trials have been undertaken on both sides of the A46 as a precursor to the main earthworks activities.
Installation of Filter Drainage and new Soakaway
Extensive filter drainage adjacent to the new slip road alignments have been constructed on both sides of the A46. These will form bottom of embankment drainage systems and allow the surface water to flow towards attenuation ponds.
As part of this, adjacent to the northbound onslip, a length of trench soakaway has been installed. This will allow surface water to be stored and permeate through the subsoil, reducing and slowing the outflow into Finham Brook and limiting potential damage to the watercourse and its environment.
Root Cutting of Retained Trees
The carriageway alignment has been designed in such a way as to retain as many trees as possible. However, in the area in the vicinity of Dalehouse Lane Roundabout (known as the Beekeepers), there are some mature oak trees that are to be retained but will be directly impacted by the new road. Consequently, these trees have required some works to preserve them and ensure they can survive the construction and operation of a new road alongside them.
Controlled tree cutting by WCC’s own forestry team has been completed alongside root cutting which will prevent any further damage to the trees during the construction works. Further to this, to encourage growth and repair for the trees, an air injection ‘decompaction’ process has been completed around the roots. This process also included the injection of a nutrient blend that helps the tree recover. Finally, the trees have been mulched to lock in the moisture and ensure that the roots have sufficient water to flourish.
This whole process has been carefully planned and completed to mitigate the project’s effect on the surrounding area whilst still enabling the works to take place.
Flood Compensation Area
Due to the required alignment of the new Westley Bridge, a large area of the flood plain alongside the existing Westley Bridge will be lost to facilitate the construction of the new bridge. In order to compensate for this, an area on the opposite side of the Westley Bridge (within the Beekeepers Area) is to be reduced in level in order to make up for the lost flood area of flood plain. Excavation has begun with the top 500mm of earth being already removed . This area is within a Himalayan Balsam contaminated perimeter and it is illegal to allow the spread of this plant as it is considered an invasive species. Therefore, this work has been meticulously planned to ensure that no contamination is spread beyond the existing perimeter.
Further Information
In the coming months, earthworks operations to construct the new northbound onslip road and southbound offslip road will continue. Drainage systems will be completed, and work will commence on construction of the two new bridges – one over the A46 and one over Finham Brook.
It is expected that the traffic configuration of the existing northbound onslip and southbound offslip roads will be amended to allow the works to proceed. This will be conducted overnight with temporary arrangements being put in place. Traffic management on the northbound onslip road and southbound offslip road will remain in place whilst works near the A46 are completed. This is necessary for the protection of the public and road users as well as that of the site operatives.