Watercare is relining the 19 km Eastern Interceptor in Auckland as part of its $8 million per year wastewater targeted asset renewal program which aims to add resilience to the network.
The Eastern Interceptor is a 19 km concrete trunk sewer, responsible for carrying around 60 per cent of the city’s wastewater from Okahu Bay to Māngere Wastewater Treatment Plant.
Project Manager Frank Lin said that the work has been delayed due to recent high rainfall which has caused high water levels.
“Because the high volume of wastewater in the network, our team cannot enter the Eastern Interceptor safely,” Lin said.
The work will be carried out in sections over the next five years, currently targeting the area in the industrial heart of Mt Wellington.
Watercare’s project partner for the work is construction firm March Cato
“The project team has constructed a 3.2m-diameter access chamber to allow them to lower trenchless technology to help fix the biogenic deterioration caused by bacteria commonly found in a wastewater system,” said Lin.
Eroded concrete is being removed and corroded surfaces being repaired with reinforced steel before being relined with a 100 per cent calcium aluminate solution.
The solution is designed to bond well to moist surfaces and provides solid rehabilitation in a short time frame.
“Due to the rain subsiding in the last couple of days, our team hopes to be able to safely re-enter the Eastern Interceptor to continue relining and repair work this week,” he said.
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