Closures begin May 31 for exit ramps at State Route 18 and Interstate 5 in Federal Way.
The state Department of Transportation has announced detours as crews complete construction of new flyover ramps. The construction is part of the $112.5 million Triangle Project, which refers to the interchange in Federal Way where State Route 161 (Enchanted Parkway), SR 18 and I-5 all meet.
Closures and detours
• Beginning May 31, crews will close the ramp from Weyerhaeuser Way to westbound SR 18. The closure will last about three months, with the ramp opening before Labor Day weekend. A 4-mile detour route will be available for the estimated 4,300 daily drivers who use the ramp. Drivers will need to take eastbound SR 18 to the West Valley Highway (SR 181) exit, then merge on to westbound SR 18. The detour is expected to take about five minutes, said project engineer Aleta Borschowa.
• During the weekend of July 15-18, the ramp from eastbound SR 18 to southbound I-5 will be closed. Crews will connect portions of the new flyover ramp to SR 18 and I-5. A detour for traffic will run on northbound I-5 to South 320th Street and back to southbound I-5.
• Throughout most of August, the ramp from westbound SR 18 to northbound I-5 will be closed. Crews will connect the ramp to the rebuilt Weyerhaeuser Way ramp and also build freeway walls. A detour for traffic will run along northbound State Route 99 (Pacific Highway South) and South 320th Street. This 8-mile detour along SR 99 is expected to take at least 15 minutes; city traffic engineers will adjust the timing of traffic signals along the detour’s arterial roads, according to Borschowa. Drivers coming from Auburn can use northbound State Route 167 and westbound State Route 516 to connect with northbound I-5. The ramp is expected to re-open before Labor Day weekend.
The big picture
• The closures only involve exit ramps to State Route 18. Interstate 5 will remain open to commuters throughout the summer, with a handful of nighttime closures for I-5 in the fall; these closures will involve installation of large steel bridge girders over I-5 and SR 18.
• Inclement weather could possibly delay completion of construction, according to Borschowa.
• All major work on the Triangle Project is expected to be finished by late fall 2012. The original cloverleaf interchange was considered “state of the art” when built in the early 1960s, according to Borschowa. Now, that interchange cannot adequately accommodate the high volume of traffic. Sideswipe accidents occur frequently at the interchange, with at least 600 accidents in the past five years, according to Borschowa.
• Approximately 3,600 freight trucks, many coming to or departing from Federal Way, use State Route 18 to access Interstate 5 daily. The construction is expected to eliminate what has been dubbed “a trucker’s nightmare” by the Washington Trucking Association. The new flyover ramps are expected to reduce the time it takes freight haulers to complete their runs.
Learn more
Washington State Department of Transportation offers roadwork updates online at www.wsdot.wa.gov/projects/i5/sr18sr161ic. The project hotline is (206) 440-4900.
