SEATTLE -- Work has started Wednesday on the 19-day Interstate 5 construction project that will reduce the northbound lanes by half starting this Friday night, reported KIRO 7 Eyewitness News.

Overnight this week, two northbound lanes near the Interstate 90 interchange will be closed, Department of Transportation officials said.

Four crews are starting work now so they’ll have less work to do during the 19-day closure, officials said.

VIDEO: I-5 Construction Starts Early

DOT spokesman Stan Suchan said the current work involves scoring the concrete so it can be removed next week as well as preparing signs and re-striping to begin shifting some northbound lanes over.

“Drivers may get their first taste of the closure to come with some lane shifts that could appear as early as Thursday morning,” said Suchan.

Thirty-four expansion joints will be replaced in the north and southbound lanes from the West Seattle bridge to the I-90 interchange, requiring around-the-clock lane closures. Officials said half the drivers who use I-5 will need to find alternate routes.

Alternates include options like Interstate 405, Highway 99, carpooling, riding the bus, taking the Sounder commuter rail train or simply staying home.

DOT officials said contractors have an incentive to get the I-5 construction done as soon as possible, as they could earn $100,000 for each day that the project is finished early.

The first day of the I-5 closures starts Friday at 10 p.m.