Auckland city council stormwater capital works programme: Cox's Creek

Cox's Creek, in Auckland's Westmere, is a tidal channel that flows through Cox's Bay Reserve before entering Waitemata Harbour. The creek is fed by a number of stormwater outlets that drain the Grey Lynn catchment, and from time to time it also receives sewer network overflows.

UPDATED: 12 OCTOBER 09

Stage 1 of the improvement works at Cox's Creek has recently been completed. The design of Stage 2 has been revised slightly as a result of feedback received from members of the public and Ngati Whatua. It is now proposed to extend works up the Wharf Rd arm of Cox’s Creek to mitigate odour issues experienced in this area as well, and leave the pool adjacent to Richmond Rd until the completion of Stage 2 (to determine if filling is actually necessary to achieve the goals of the project). Extensive riparian restoration planting is also proposed, and we look forward to the ecological and amenity benefits that the project will bring to the creek and park.

Unfortunately, budget cuts and the subsequent re-prioritisation of projects have meant that Stage 2 works are now scheduled for the 2010/2011 earthworks season, subject to financial availability and obtaining resource consents.

BACKGROUND

Poor water quality and odour have long been a problem at Cox's Creek, and studies have been undertaken to assess the causes of the pollution issues and the creek's most effective management options.

The first step in solving the problem is to reinstate tidal flow, which will help improve water quality. We will do this by removing polluted sediment that has clogged the creek and clearing points of water constriction and ponding.

To reduce the sewage overflows, Metrowater has installed grit traps to help prevent wastewater pipe blockages, and will be separating some local combined stormwater-wastewater pipes in the near future.

In the longer term, the aim is to separate the major combined stormwater and wastewater networks in the city. These large scale works are still some time away, as they will need to fit with a wider regional drainage strategy.

Before the first stage of works can take place (reinstating suitable tidal flow in Cox's Creek), the council needs to obtain resource consents.

For more information, please see Auckland City Council's website.