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Progress on triangle project unfolds at Federal Way I-5 exits
Progress on the triangle project — improvements to the Interstate 5, Highway 18, Highway 161 interchange — can be seen near the Highway 18 on-ramps and off-ramps. Crews are currently constructing, on the west side of I-5 South, a fly-over ramp to connect the interstate and Highway 18.
The new design will improve motorists' safety and relieve traffic congestion. Construction will be completed in two phases. The first phase will replace the interchange's two cloverleaf on/off-ramps with flyover ramps. The flyovers will connect traffic from westbound Highway 18 to southbound I-5, and eastbound Highway 18 to northbound I-5. Direct access to Highway 161 from southbound I-5 and westbound Highway 18 will also be provided via new exit ramps at South 356th Street and South 359th Street. Work is expected to take two and a half years to finish. Click here to read more about the project and view a map.