Work is continuing to restore gas supplies to some Whanganui consumers but, when that's completed, there'll be a review of how the issue has been dealt with.
That will involve the Whanganui District Council, whose water pipe created a hole in a gas main, and GasNet.
Gas was cut to 282 properties on Sunday, February 9, and GasNet representatives expected to have visited 256 affected consumers by the end of yesterday .
GasNet general manager Geoff Evans said not all supplies have been restored due to consumers not being home at the time representatives called. Faults in the consumer's installation may also cause delays in restoring their supply.
Gas was reintroduced to Argyle, Barrack, Glasgow, Gloucester, Halswell, Keith, Russell and Tay streets on Tuesday.
Evans said once a reliable supply had been established in Somme Pde the remaining streets would be have water removed from the gas main and the supply would be reintroduced.
At the current rate of progress, restoration will be completed by the end of the week, Evans said.
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"There are many utility pipes and cables in the road reserve that can affect each other when a fault occurs. It was just extremely unfortunate that in this instance a leak in a water pipe resulted in failure of the adjacent gas pipe with such extreme consequence."
Evans said GasNet and Whanganui District Council's infrastructure team and chief executive Kym Fell have maintained good communication since the outage began.
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Fell said council staff were still trying to determine what caused the water pipe to leak and were looking at objects around the pipes, such as large stones.
He said council has tried to ensure GasNet feels supported and has offered to assist if needed.
"I've been impressed with their responsiveness of how they've gone about trying to accommodate some of the displaced customers," Fell said.
"We and GasNet should be measured on 'how did they respond and have they fixed it and how can we ensure it doesn't happen again'."
Fell said it was hard to determine who was at fault for the outage as the water leak could have occurred from anything, including the earth moving.
He said the council carried out condition reports on its network by sending robot-type devices down the water pipes to look at the condition of the pipe.
"This is done regularly but it's quite difficult though when we've got such a large network of pipes, so it's making sure we know the condition of pipes when we should be renewing them."
He said council has a good renewal system in place to make sure pipes are not past their expiry date.
Once all consumers' supplies have been restored, Fell said he will have a debrief on the council's response times to the outage and to see how they could have supported more.
"We'll certainly be working closely with GasNet and [council's] infrastructure team to see if there's any learning from what's occurred."