Eight million litres of contaminated water is being pumped from the basement of the SkyCity International Convention Centre into Auckland's wastewater network.
Watercare has confirmed to Auckland Council that the water will be released into the wastewater network at a rate of 25 litres per second.
Watercare crew will be in the area monitoring manholes to ensure there are no problems arising from the operation.
Water samples have been tested and Watercare say they're confident that this discharge will not affect the safe operation of the network.
Earlier the water was being pumped into the viaduct harbour near Beaumont St.
For now a water hazard alert has been issued for St Mary's Bay warning the public of "reports of hazardous substances released into bay."
Now the convention centre fire is contained, Fire and Emergency NZ hope to reduce the cordons around the SkyCity precinct and SkyCity has reopened the casino.