Work to repair a stretch of deteriorated pavement on Montauk Highway, near Mecox Lane, in Water Mill is expected to be completed Friday, the agency said.
Single lane, alternating directional travel is in effect between 10 a.m. and 3 p.m. daily.
Both eastbound and westbound motorists are being stopped briefly so a single lane of travel will be alternately in effect.
Brief intermittent full closures of Route 27 may also be in effect to move construction equipment, the agency said.
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