WSDOT is preparing for the Rest of the West, the remaining phases of construction on SR 520 between Lake Washington and I-5. First up is the Montlake Project, where construction may begin as early as May. For transit riders, this means the Montlake flyer stop and the transit-only lanes on the Montlake Boulevard exit will both close in June. Several planned mitigations will blunt the impacts to transit riders.
The closure of Montlake flyer stops means buses not exiting the freeway will no longer stop in the Montlake area. In mitigation, WSDOT is funding additional weekend and evening service on Sound Transit route 542 through March 2020. That added service commenced with the March 2019 service change. The closure of the freeway stations are targeted for June 15.
In October 2018, WSDOT opened a temporary transit-only lane on the westbound ramp to Montlake Blvd. The lane, about 1100 feet in length, allowed buses to go almost to the top of the ramp before merging to the front of the queue of cars waiting to turn to Montlake Blvd. Originally scheduled to operate for just six months, the lane was extended three more months as the construction schedule was worked out. It has been very popular with transit users who have seen significantly better bus performance in the area.
Beginning June, that lane will also close. The existing exit ramp will close and be replaced by a narrower temporary ramp along the north edge of the work area. In this more constrained space, WSDOT could make room only for two general purpose lanes and a pedestrian-bike connection to the SR 520 trail. At the request of Kirkland and other Eastside cities, WSDOT studied options to maintain the transit lane, but none appear feasible.
Four options were considered. All would be shorter than today. Concept A would create a 600 foot transit lane in place of the bike-ped lane. Concept B would also take the bike-ped temporary lane for an 800 foot transit lane, but with 24th Ave exit traffic in the general purpose lanes. Concept C would take a general purpose lane to create a 1,000 foot transit lane. Concept D creates a 200 foot transit lane on the south side of the ramp west of 24th Ave.
The added cost of a transit lane would be $3-4 million, and none of the options would allow the lane to remain in place longer than nine to ten months. There are also neighborhood concerns about the remaining trees between Hamlin St homes and the SR 520 work area. The benefits would be just one to two minutes of travel time for transit users, mostly in the evening peak.
The case for a new transit lane at Montlake is weakened further by the delay of the North Eastside Mobility project. The restructure of Kirkland area bus routes will route Metro 255 buses to Link at UW Station. Previously planned for the Fall 2019 service change, the restructure is delayed due to concerns about rail reliability and headways during Connect 2020. That project connects East Link rails to the main line near International District / Chinatown Station. It requires single-tracking of trains through downtown for ten weeks, and train-train connections at Pioneer Square. With headways between UW and Downtown dropping to 12 minutes and total Link capacity reduced, it would have been impossible to provide the promised rapid bus-train connections for the ten weeks when rail service is disrupted.
WSDOT will implement two other approaches to support more reliable bus travel in the Montlake area.
There will be an extended transit/HOV lane on the SR 520 bridge deck. As work begins on the West Approach Bridge South, all traffic will move to general purpose lanes on the West Approach Bridge North. The highway configuration will resemble that in 2016 when three lanes of westbound traffic merged to two approaching the west shore. On this occasion, the transit/HOV lane will end a half-mile further west and closer to Montlake. This modification is anticipated to yield about a minute of travel time during peak hours for buses to both UW and downtown Seattle.
WSDOT and SDOT will replace signals on Montlake Blvd before major construction begins in June. Signals will be upgraded at E Shelby St, at E Hamlin St, and at each of the ramps. Currently those signals are not interconnected which unnecessarily contributes to traffic congestion on Montlake Blvd and on the westbound off-ramp. Connecting these signals to each other, and to the SDOT traffic operations center will yield more efficient movements for all vehicles, and ease the bottleneck at the end of the ramp.