March 2018 to March 2019
Christchurch City Council
The Sparks Road Wetland at 270 Sparks Road involved the construction of forebay ponds and two large wetland cells. This was to provide secondary treatment of stormwater runoff from the adjacent Halswell Commons Subdivision and other existing catchments, before discharging back into Cashmere Stream. Discharge was via the enhanced Hendersons Drain, which was diverted and
naturalised into the site to create habitat for native flora and fauna.
Work was started late in the construction season and a significant period of poor weather led to a mutually agreed site shutdown.
Concurrent works to the Quarryman’s Cycleway along Sparks Rd.
The full scope of the project included site set out, site clearing, grubbing and tree removal.
Extensive earthworks were undertaken to construct the forebay and outlet ponds along with the two wetlands areas.
The project included drainage works and associated stormwater culverts and weir structures. The surrounding site was formed to allow for passive recreation for walkers and cyclists with footpaths mounded above the flood level around the perimeter, as well as lower lying, less formal paths transecting the wetland cells. New timber boardwalks were installed to complete a full circuit of the reserve.
GSL’s in house landscaping team acknowledged the history of the site by planting native trees, shrubs and wetland species, as the Hendersons Basin area was originally a lowland swamp.
Towards the end of the project the client added the construction of a new asphalt car park into the scope. This completed a full amenity facility that was warmly welcomed by the local community.
Take a look: