Washington State has provided funds to grade separate the 520 Trail from vehicles at NE 40th St. The project will construct a tunnel under NE 40th St near the westbound SR 520 ramps. During construction, a detour for trail users will be in place along NE 36th St, 150th Ave NE, and NE 51st St (SR 520 Trail Detour (PDF)).
Pedestrian and Bicycle Improvements
The tunnel will enhance safety by moving much of the pedestrian and bicycle traffic away from the vehicular traffic on NE 40th St. Travel times will also be reduced as tunnel users will not have to wait for the traffic signal. The tunnel is expected to attract additional walking and biking traffic to the area by increasing access to the freeway flyer stop, the Redmond Technology Light Rail Station, and Microsoft.