Proposed replacement option
The proposed option is new pipeline bridge, crossing Te Awa Kairangi / Hutt River between the Silverstream rail bridge and the weir encasing an existing wastewater pipeline.
The proposed design is a network arch bridge that crosses both Te Awa Kairangi / Hutt River and the Wellington Fault at an angle which allows the new bridge and pipeline to articulate over the fault when it moves.
The bridge has been designed in accordance with Hutt River Flood Management Plan, and provides a safe platform for maintenance over the service life of the new asset.
Pedestrian and cycling linkages
Improvements to the new bridge approaches would provide connections to existing and planned cycle routes in the area and address a missing link in the region's pedestrian and cycleway network.
As part of the new pipe bridge, there is an opportunity to incorporate a pedestrian and cycling path on the bridge deck. This would provide a safer route to State Highway 2, connections to the Hutt River Trail, and connections to the planned cycle path through Manor Park Golf Course to Manor Park Train Station. This will mean that cyclists wouldn't need to cross the busy State Highway 2 and Fergusson Drive intersections, and provide a safer crossing over the Te Awa Kairangi / Hutt River rather than the narrow pathways on the Silverstream road bridge.
Working with technical specialists, some 28 options for the pipe alignment have been assessed against a range of critical criteria, including seismic resilience, construction effects, environmental impacts and short-listed down six options.
These have been further assessed in collaboration with project partner Greater Wellington Regional Council's Flood Protection Department and with iwi Taranaki Whānui.