Q: Why don’t road construction crews do their work at night instead of in the middle of the day when traffic gets congested? In places like Chicago, road work is done in the night time to avoid that kind of problem.

A: There are a few reasons: overtime pay, safety concerns and difficulty in receiving supplies.

City engineer Brian Johnson said a lot of Manhattan’s road construction is contract work, which means that if crews work at night, a contractor would have to pay overtime.

“That contractor would be paying their crews overtime as would we,” Johnson said. “We’d be paying them overtime to work in the middle of the night or a shift differential to work those night hours, so you’re probably going to add 10% to 15% to the cost of a project. We do about $4 million of road work a year.”

That’s an increase of about $600,000 a year, Johnson said.

Also, it is more dangerous for crews to work at night because drivers may not see workers, cones or other equipment, Johnson said.

“Even though there is less traffic, the traffic that is out is certainly more dangerous because it’s dark,” he said.

The last reason, Johnson said, is that it is hard for crews to receive materials and supplies, such as lumber and steel, late in the night.

“You’re not going to get all that stuff after 5 or 6 o’clock at night,” Johnson said. “You’re not going to get it in the middle of the night. So there’s all sorts of logistics issues to working in the middle of the night, not to mention just the safety.”

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