Westchester Drive Link Road
This project, which involved constructing a new 800m section of road connecting Westchester Drive in Churton Park with Middleton Road in Glenside, is now finished.
The new bridge over Stebbings Stream under construction
Work started on the project in March 2011.
The aims of the new link road were to:
- provide direct access to State Highway 1 for Churton Park and Stebbings Valley residents
- ease peak-hour congestion along Johnsonville Road
- reduce through-traffic in Churton Park
- provide an alternative route for emergencies
- allow for new, more direct bus routes
- include a footpath on the stream side of the road.
The new road is expected to carry about 2,500 vehicles a day at first, but this could increase to 8,000 to 9,000 vehicles a day. When Stebbings Valley is fully developed, it will have about 800 houses and a shopping centre and school.
The two bridges, earthworks, retaining walls and the new roundabout at Middleton Road are all complete. Below ground, new water and sewage mains have been installed along with ducting pipes for gas and power and telecommunications cables.
The following work is also completed:
- building the kerbs, footpath and streamside barrier fences
- surfacing and sealing the road
- hydro-seeding the areas where the most significant earthworks have occurred
- planting about 4,500 native plants on the recontoured hillsides and stream edges.
Plan of Work (4MB PDF)
Simulations of the completed project
These simulations show how the completed road and bridges look from:
Creating the link road involved building bridges at both ends and diverting a section of Stebbings Stream, a tributary of the Porirua Stream.
The road design took into account the importance of protecting the stream and the environment.
Rather than the stream disappearing underground in places - through culverts - which was the original plan, it has instead been bridged to better protect the stream and stream life.
The new section of road fits the area's topography and closely follows the natural contours. More curves were included in the design to minimise the stream diversion work.
Stormwater will also be filtered before it gets to the stream to remove litter and other pollutants. Most of the water will go down roadside drains and into one of three swales - grassed depressions next to the road. These have been constructed to collect run-off, which will gradually drain through the grasses leaving any residues behind. The stormwater that can not be discharged through a swale will instead be channelled through purpose-built interceptors so that it will also be filtered before it reaches the stream.