A monitoring system has been fixed to a slumping bridge in Masterton.
The southbound Colombo Bridge, which crosses the Waipoua River is set to undergo a $2.8 million renewal this year.
But residents have expressed concern about whether it is safe to use in its current condition; there is a noticeable slump halfway across the bridge.
Masterton councillor Gary Caffell said a number of residents had contacted him over the past week about the "slight dip".
"It's making people a little bit nervous," he told fellow councillors and staff at this week's Infrastructure and Services Committee meeting.
"I know you said it's stable and it's fine, and I'm sure it is," he told chief executive David Hopman.
"But there are a number of people who are taking a lot of convincing about that."
Hopman said a tender for the bridge's renewal was set to close today.
The scope of work includes the demolition of the existing bridge, footpath, and cycleway; the temporary relocation, protection, and continued operation of the sewer main; and the design and construction of the replacement bridge.
Hopman said he was keen to get the work underway "as soon as possible".
"There is a slight dip in that bridge now; it has moved but it is stable," he said.
"We are currently monitoring that bridge in case something does happen, to minimise that risk."
He confirmed it was safe for vehicles to use with the monitoring the council was doing.
Masterton District Council roading services manager Kaine Jaquiery said the bridge slump was due to river degradation and the piles not being embedded deeply enough in the riverbed.
"If you go down, you can see the pile caps - the steel bits they use to drive the piles in - they're sticking out of the river," Jaquiery said.
"It's been on our repair list for quite a while and we are just having tenders close this week for the replacement of the bridge.
"In the meantime, we have a monitoring system on the bridge that measures tilt and slump with digital probes.
"If it triggers anything abnormal, we will be immediately closing it."
Should the bridge need closing, traffic would be reduced to one lane over the northbound section of the bridge.
The northbound section was built in 1973, whereas the southbound section was built in the 1920s.
Work on building a replacement bridge would be funded by Masterton District Council and the National Land Transport Fund.
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