Wastewater is flowing into Wellington harbour from a second site, although on a much smaller scale than last week's leak that has caused major disruption to the central city.

Photo: RNZ / Rob Dixon

Crews are working around the clock to build and install a temporary overground wastewater pipe to replace the damaged old pipe that's been sending sewage flowing into the harbour.

Wellington Water said it expected to finish installing the above-ground pipe later today. The pipe is 600mm in diameter.

Meanwhile, a leak or blockage near a pumping station in Eastbourne is causing the intermittent discharge of wastewater into the harbour at Sunshine Bay.

The pumping station services about 70 houses.

Wellington Water said it hoped to find and fix the problem today.

We’re working to find and repair the leak as quickly as we can.

At this stage we are unable to confirm the volume of the discharge. The affected pipe serves about 70 households in the area. https://t.co/MmXQf7y65T — Wellington Water (@WgtnWaterNZ) December 23, 2019

A collapsed pipe caused more than five million litres of sewage to spill into the harbour since Friday morning.

City traffic will continue to be disrupted with streets closed so urgent work can be done on fixing the wastewater system.

Parts of Willis and Ghuznee streets remain closed, and Vivian St will be closed overnight this week from 8pm to 8am.

Overground sewerage pipes are being installed at the top of Willis St and will be used for another two months before a permanent solution is in place.

Wellington Water said they hoped to return to a stable system by the end of February next year.