Drivers should plan for nighttime lane and ramp closures on I-5 and State Route 18 in Federal Way during the next few weeks.

Crews working for the Washington State Department of Transportation (WSDOT) have started installing steel girders for two new flyover ramps at this busy interchange. To keep drivers and crews safe, the work will require nighttime closures as cranes lift the large bridge girders adjacent to and over the highway. Signed detours will be in place for all complete closures.

This week’s closures are as follows:

Monday, Feb. 6 to the morning of Friday, Feb. 10: Crews will close the three right lanes of southbound I-5 near SR 18. The first lane will close at 8 p.m., the second lane at 10 p.m. and the third at 11 p.m. All lanes will reopen by 6 a.m. daily.

Monday, Feb. 6 to the morning of Wednesday, Feb. 8: Crews will close the following ramps from 8:30 p.m. to 5 a.m. nightly:

• The ramps from eastbound and westbound SR 18 to southbound I-5.

• The ramp from southbound I-5 to eastbound SR 18.

Wednesday, Feb. 8 to the morning of Friday, Feb. 10: Crews will close the following ramps nightly from 9 p.m. to 5 a.m.:

• The ramp from westbound SR 18 to southbound I-5.

• The ramp from southbound I-5 to eastbound SR 18.

Driver alert: Friday, Feb. 10 to the morning of Sunday, Feb. 12 – Crews will close all lanes of southbound I-5 at SR 18 Friday and Saturday nights. Lanes begin closing at 9 p.m., with all lanes closed at 11 p.m. The southbound lanes will reopen by 7 a.m. each day. A five-mile signed detour will direct drivers onto South 348th Street to Highway 99, then to 54th Avenue East in Fife to rejoin southbound I-5.

This work is part of a $112 million project to build two new flyover ramps – one between westbound SR 18 and southbound I-5, and the other between eastbound SR18 and northbound I-5. The ramps are expected to open this summer.

For more information on the project, go to: www.wsdot.wa.gov.