The Mercer West Project will complete the City’s vision for a direct, two-way connection between I-5 and Elliott Avenue W by moving construction west of Dexter Avenue N. The project, which will begin construction in early 2013, will reconstruct the SR 99 bridge over Mercer Street, widen the underpass at Aurora and add bicycle and pedestrian-friendly improvements throughout the corridor.
The widened Mercer Underpass will provide three lanes of traffic in each direction, left turn lanes, plus a 25’ combination bike path and sidewalk on the north side and a 16’ sidewalk on the south side (considerably wider than the current 5’ sidewalk width). Additional project benefits include:
- Converting Mercer Street to two-way operation with two lanes in each direction and turn pockets between Fifth Avenue N and Queen Anne Avenue N;
- Converting Roy Street to a two-way street with bicycle lanes between Fifth Avenue N and Queen Avenue N;
- Creating a new Sixth Avenue N connection between Mercer and Harrison Streets that curves around the Gates Foundation Campus to its west;
- In conjunction with the Alaskan Way Viaduct Replacement Project, closing Broad Street to re-connect the street grid between Ninth Avenue N and Fifth Avenue N, reopening John, Thomas, and Harrison Streets across Aurora Avenue N.
Converting Mercer and Roy Streets to two-way operation
- Two lanes in each direction on Mercer Street (Fifth Avenue N to Second Avenue N);
- One lane in each direction on Roy Street (Fifth Avenue N to Queen Anne Avenue N);
- Bike lanes on Roy Street;
- All changes occur within the existing right-of-way
West Mercer Place
The Mercer West Project Team did an evaluation of options to improve traffic operations and pedestrian and bicycle connections on W Mercer Place near Elliott Avenue W. The purpose of the evaluation was to determine if improvements were justified, based on the potential benefit (reduction in delay or travel times) and the estimated costs and impacts of such improvements.
Their conclusion was that extending the double left-turn lanes on Elliott Avenue W was the only cost-effective option at this time. After sharing their findings with stakeholders and community members and receiving feedback, the double left-turn lanes were extended in 2011. Engineers will continue to monitor operations and make adjustments, if needed, on Elliott Avenue W, Nickerson Street, and Mercer Street through the Alaskan Way Viaduct Replacement and Central Waterfront (Alaskan Way and seawall) construction.
