Road to close with 30-mile diversion
Urgent attempts to tackle gas leaks will see a month-long road closure and drivers forced to use a 30-mile (48km) diversion.
Gas company SGN will begin work to replace a main pipe on the A350, in Dorset, on 18 November.
There will be no through vehicle access in either direction on the road past Sturminster Marshall until 16 December.
SGN apologised for the inconvenience caused and said a signed diversion route would be in place.
The firm said this was due to the complexity of the engineering work required, with the gas main crossing the centre of the road and the need to use large machinery on the site.
The A350 will be closed from the A31 at the Roundhouse Roundabout to the north side of the crossroad junction with Dullar Lane and Station Road.
SGN confirmed bus routes in the area would be maintained, as will pedestrian and cycle access.
It said the improvements will reduce the risk of gas leaks in the future.
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