Once it is complete in late 2012, the 800 metre-long extension to Westchester Drive will also reduce through-traffic in Churton Park and allow for future, more direct bus routes. The new section of road will stretch from Lakewood Avenue in Churton Park to Middleton Road in Glenside, involve major earthworks and the construction of two new bridges.
Wellington City Council's Transport Portfolio Leader, Councillor Andy Foster, says the new link will provide Churton Park and Stebbings Valley residents with direct access to State Highway One.
"This will significantly improve travel times and distances for many residents in the area and reduce traffic on the Churton Park and Johnsonville streets that people currently use as through routes to get to the motorway.
"Halswater Drive is the main road in and out of Churton Park and Stebbings Valley at the moment and the amount of traffic using it is a safety concern for local residents. The new link road will divert a significant amount of this through traffic, which will make it possible to develop safer walking and cycling routes to Churton Park School."
The new road is expected to carry about 2500 vehicles a day at first but this could eventually increase to 8000 to 9000 vehicles a day. When Stebbings Valley is fully developed, the suburb is expected to have some 800 new houses as well as a shopping centre and school. Cr Foster says the new road will directly connect with the planned new Churton Park shopping centre, which is under way.
"It is going to be very important in making the centre work," he says.
Some preliminary clearing along the route has already been carried out. There will be some activity at the Lakewood Avenue end at first, where the site office is being established, but most of the early construction work will be concentrated at the Middleton Road end where a new roundabout and bridge will be built. The bridge will provide access so the new road can be developed on the other side of Stebbings Stream and over the next year some 55,000 cubic metres of earth will be progressively removed from the area - around 30 to 40 truckloads a day.
Cr Foster says the original plans were for a road alongside and on top of the stream but for environmental reasons and because the stream is very important to the local community, seven alternative options were explored.
"I'm very pleased that as a result we will be bridging the stream rather than putting in culverts, which will be better for the environment and local residents."
Rather than a road alignment that would have followed the shortest and straightest route, a more sympathetic route was agreed. More curves have been incorporated to minimise stream diversion work and slopes will be cut at 45 degrees and rounded to provide a more natural looking landscape.
Cr Foster says stream protection is very important and a lot of measures have been put in place to monitor the health of the stream. These are reflected in the Greater Wellington resource consent conditions and include silt fences and ponds and agreed trigger points.
"Management plans have been developed so that prompt action can be taken to protect the stream if tests results indicate subtle changes in water quality."
Once construction work is complete, native plants will be planted on the re-contoured hills and along the stream. A footpath will run along the road on the stream side. The work will be carried out by Fulton Hogan.
The road is expected to cost approximately $8 million. Ratepayers will pay for about half while the remainder will be funded through contributions paid by developers as new areas of Stebbings Valley are developed. The road will allow the area to grow without overburdening existing routes.