The closures are taking place Sundays to Thursdays from 10 p.m. until 5 a.m. in Islip for approximately four weeks while crews repave the roadway, officials said.
One eastbound lane will be closed between 8:30 p.m. and 10 p.m.
Eastbound traffic on I-495 will be detoured onto South Service Road between Sagtikos State Parkway (Exit 53) and Veterans Memorial Highway (Exit 57) in Islip.
The roadwork started at 10 p.m. Thursday, June 16.
Transportation officials urged drivers to slow down through the stretch and reminded motorists that fines are doubled for speeding in a work zone.
You can find the latest travel information by calling 511 or visiting 511ny.org.
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