Motorists heading out of Palmerston North towards Summerhill and Aokautere face a detour and delays this weekend.
The Tennent Dr lane to Summerhill Dr will be closed to allow urgent replacement of the cast iron lid on a 3-metre deep Telecom chamber.
The closure will apply from 9.30pm on Friday to 9.30am on Monday.
City council programmes team leader Rob Campbell said the lid on the deep chamber was cracked, and a safety risk.
"It's still serving its purpose, but it will fail in the near future.
"It has not failed catastrophically, yet, but if it did, a vehicle's wheel could drop down and probably damage a car beyond repair."
Mr Campbell said the work had been set down for the weekend to minimise disruption for the 4000 to 6000 vehicles that used the route each day.
He was also keen to see the work carried out before Massey University students returned.
The narrowness of the road and steep drops at the sides meant it was not safe to keep even a low-speed, light vehicle lane open past the work crew.
A detour has been put in place that will direct Summerhill-bound traffic along Tennent Dr to do a U-turn at Dairy Farm Rd, opposite the university, to return to the flyover via the city-bound lane from Tennent Dr.
A temporary 50kmh speed restriction will be put in place to slow traffic approaching the city and reduce risks for turning traffic, and there will be a traffic controller in position.
"There will, no doubt, be delays, and there may be some backing up of vehicles waiting to make the turn."
Large vehicles, in particular, would cause delays as they would need space to cross both lanes.
The only alternative to the U-turn would be for vehicles to continue all the way to Old West Rd and loop back toward Aokautere.
- Manawatu Standard
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