Western isthmus water quality improvement

Project aims

The programme aims to significantly reduce wastewater overflows into the Waitematā Harbour and reduce stormwater entering the wastewater network.

It involves numerous major infrastructure improvements to the stormwater and wastewater network in collaboration with Watercare.

Other goals include:

• reduce risks to public health
• remove the permanent health warning status of both Meola Reef and Cox’s Beach
• reduce intermittent beach closures in this area over the next 10 years.

Current infrastructure work

Some of the major projects already underway:

• St Mary’s Bay and Masefield Beach improvement project to reduce overflow frequency at these two beaches from over 100 times a year to twenty (stage 1) and then six (stage 2)
• St Mary’s Bay and Herne Bay piping separation
• Work to separate the stormwater and wastewater networks at Waterview is due to start in 2020 and be completed by 2025. The design work is being led by our Healthy Waters team.

The current work complements Watercare's Central Interceptor programme, a 13 km pipeline costing $1.1 billion expected to be completed in 2025.