• Mountains to Sound Greenway Trail

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    MTSG east of Factoria Blvd.JPG

    The Mountains to Sound Greenway is a 100-mile long corridor along Interstate 90, stretching from the Seattle waterfront to Ellensburg in Central Washington. It features hiking and biking trails and a regional trail network used by pedestrians and bicyclists for recreation and transportation. The 3.6-mile trail project in Bellevue will close a gap in the Mountains to Sound Greenway Trail between Factoria Boulevard and Lakemont Boulevard.


    Construction on the first phase of trail improvements in Bellevue began in September 2019 to build a 12-foot pedestrian/bicycle path, a pedestrian/bicycle bridge over Factoria Blvd, a tunnel under the existing I-405/eastbound I-90 ramps, relocate portions of the trail and install additional lanes on the I-90 eastbound off-ramp to Factoria Boulevard. Details in construction alert (August 2019). Construction is expected to be complete by the end of 2020.

    image of MTSG project


    In 2013, the city began the final design on the Greenway Trail between Factoria Boulevard Southeast and 150th Avenue Southeast. The design follows recommendations made in the Mountains to Sound Greenway Trail Design Study. The alignment was chosen as part of a study of the entire Eastgate/I-90 corridor. Sections of the trail in Bellevue include:

    • Interstate 405 to 132nd Avenue Southeast: Provides a tunnel crossing under the I-90/I-405 ramp and a pedestrian/bicycle bridge over Factoria Boulevard Southeast to ensure bicycle and pedestrian safety. Portions of the trail will be relocated to improve capacity for the eastbound I-90 off-ramp to Factoria, helping to avoid long backups onto the highway. Status: Under construction Sept. 2019-end of 2020.
    • 132nd to 150th Avenue Southeast; This section will include a 12-foot-wide paved pedestrian and bicycle path on the north side of Southeast 36th Street. It will include walls, traffic signal modifications, new lighting and new pavement.
    • 156th Avenue Southeast to Southeast Lakemont Boulevard: Section will include a new 12-foot-wide pedestrian and bicycle trail, along the south side of I-90.

    Several ideas were considered as part of the Eastgate/I-90 Land Use and Transportation Project on how to address the “Eastgate Gap.” Community input and feedback indicated that bicyclists preferred the southern alignment because it is the most direct and continuous route. A citizen advisory committee endorsed the pathway depicted in the proposed Mountains to Sound Greenway alignment. The city, in partnership with the Mountains to Sound Greenway Trust, completed a design study of trail alignment along the south side of Interstate 90.


    • 2019: Construction began in September 2019 on the I-405 to 132nd Avenue Southeast segment and is expected to be complete by the end of 2020. 


    Construction funding for I-405 to 132nd Avenue Southeast segment is $17.7 million. Construction funding for the section of trail between 132nd Avenue Southeast and 142nd Place Southeast is expected to be available by 2022. Design and construction funding for the segments from 142nd Place Southeast and Lakemont Boulevard is not yet available.

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