UPDATE | Friday 25 October, 2pm
Water quality results for the basement water of the NZ International Convention Centre came in on Thursday 24 October. Watercare carried out extensive testing to understand how the water has been affected by the fire-fighting activities.
The results found the water is well within concentration limits set by the Trade Waste Bylaw and is not toxic to the Mangere Wastewater Treatment Plant.
Auckland Council Safeswim Programme Manager Nick Vigar says Watercare is confident that the water being pumped into the wastewater network can be safely and thoroughly treated at the plant.
“Water from the basement was redirected to the wastewater network from 6.30pm on Thursday 24 October, at 25 litres per second. It will take four to six days to empty the basement, bearing in mind that water is still running into the basement.”
To further ensure the safety of the network and treatment plant, the water is being screened for solids and hydrocarbons before entering the wastewater network at a controlled rate.
At this point, run-off outside will continue to go into the stormwater system, but water testing results at the Viaduct Basin show contamination is low. The volume of external runoff is now decreasing as fire-fighting activities are scaled down.
“We will continue to monitor the water quality at key areas of the Basin until we’re confident there is no contamination,” says Mr Vigar.
“As a precautionary measure the St Mary’s Bay alert will remain on the Safeswim website.
“We’re awaiting further biological toxicity reports, which we’re expecting after the weekend. This will tell us the likely impacts on ecology in the harbour.”