Mercer Island bus-rail connection still in flux

Transit integration at Mercer Island continues to move forward, but rough water appears to be on the horizon. When we last checked in, Sound Transit and King County Metro had presented three infrastructure options, the Limited, Improved, and Optimal Configurations, which could facilitate 12, 16, or 20 buses per hour, respectively. Since that time, the Mercer Island City Council has identified additional concerns and discussed the Interchange again with City staff on July 16, 2019.

Mercer Island Station construction, June 2019. Sound Transit photo, via Facebook.

One of the significant factors is that King County Metro was not a party to the Settlement Agreement that ended litigation and other Link-related disputes between Sound Transit and the City. However Metro's "concurrence" is required for the Transit Interchange, and the Settlement Agreement allows for changes to the Transit Interchange to achieve that concurrence. As previously reported, Metro identified issues with the Transit Interchange as described in the Settlement Agreement and proposed changes that would allow Metro to concur. Notably, new information presented to the City Council included a letter from King County Metro to Sound Transit (page 16 of the linked PDF) stating that Metro cannot concur with the Limited Configuration (e.g. the configuration explicitly described by the Settlement Agreement, with a capacity of up to 12 buses per hour) because that configuration does not allow appropriate layovers and pickup/dropoff locations.

Apart from the configuration options, the City Council identified several other concerns that they wish to explore further. These include:

• Pedestrian crossing volumes and safety at the North Mercer Way and 80th Avenue SE intersection.
• Public and rider safety due to increased passenger volumes relative to today.
• The timeline for decision-making.
• Continued questions about the need for the Transit Interchange, and whether South Bellevue can be the interchange point instead of Mercer Island.
• Identification of alternatives to address potential impacts noted above.

The number of pedestrians crossing at the North Mercer Way and 80th Avenue SE intersection was estimated to average approximately 30 pedestrians per crossing sequence, assuming a 90-second signal cycle. However as passengers would arrive in buses at regular intervals and not a continuous stream, pedestrian crossing demand may be unevenly distributed. Today, pedestrian crossing demand is fairly evenly spread out in the AM and PM peaks with bus riders accessing the Park and Ride or nearby homes and offices; the Transit Interchange would add a significant number of pedestrians in the AM peak due to buses dropping off passengers on the north side of North Mercer Way (far side of the street from the light rail station), while the PM peak is unlikely to be affected much as bus loading would occur on the south (near) side of North Mercer Way.

Public safety is a concern with the number of new passengers using Mercer Island to transfer between bus and rail. There has been a lot of talk on Mercer Island social media (mostly Nextdoor) about public safety related to increased transit usage, and while a certain amount of this is noise, the discussions required the City's police chief to directly address the issue. While refusing to commit to any specific need 4 years in advance, the police chief noted they may need to keep a couple of bike officers near the station, and this could negatively affect patrol coverage of the rest of Mercer Island. The current shortage of officers (Mercer Island is short 4 officers now) could exacerbate this, but with the station opening 4 years into the future the current shortage doesn't have a specific bearing beyond noting the general challenges of allocating police resources.

The City Council and some citizens expressed a fair amount of confusion over the timeline for a decision. Sound Transit released a graphic showing the various steps in the process. While some citizens (and at least one Councilmember) believe no decision is needed until 2020 at the earliest, Sound Transit continues to advance the design of the Transit Interchange, and intends to begin 60% design this fall, with final design completed next summer. Construction would begin in early 2021 to have the Transit Interchange physical infrastructure complete by the summer of 2022, in time for the earliest possible East Link opening date (East Link's schedule contains months of "float" and an early opening similar to U-Link remains possible, but impossible to forecast with East Link currently only 55% complete). Sound Transit appears to consider the schedule fairly tight with minimal flexibility, while some citizens believe Sound Transit is needlessly pushing forward and plenty of time remains for further discussion.

The City Council voted to allow the City Manager to spend up to $50,000 on engineering consultants to both confirm Sound Transit and Metro's assumptions and assertions, and to help identify other alternatives that could reduce or change the Transit Interchange's impacts. The City Council has come to realize that the 77th Ave SE option (memorialized in the Settlement Agreement) comes with some hefty drawbacks, including increased property acquisition (notably 2 residences) and traffic impacts on North Mercer Way. The 80th Ave SE option (specifically rejected by a prior City Council) would heavily impact the 80th Ave SE overcrossing of I-90, but would isolate the majority of impacts to that overpass. When the Settlement Agreement was signed, the City Council at the time decided that keeping more in line with past agreements concerning the various I-90 overpasses and lids, specifically their landscaped nature, was a critical factor. However as the 77th Ave SE option has moved deeper into design the current City Council has decided to take another look at the 80th Ave SE option. Whether Sound Transit and Metro would agree to switch at this point is unknown; the 80th Ave SE option only reached a conceptual design level, and Sound Transit now has a 30% design for the 77th Ave SE option and is soon advancing to 60%. Anecdotal information suggests Sound Transit and Metro favored the 80th Ave SE option at the time of the Settlement Agreement even though it is more physically constrained, because it works better operationally and avoids private property impacts. Buses drop off and load directly in front of a station entrance, without street crossings, and bus circulation, while tight, does not conflict with pedestrian and car traffic.

Mercer Island appears to have little leverage here due to the tight timeline. In addition, Mercer Island staff noted that Sound Transit likely has the legal authority to unilaterally impose the Transit Interchange should the City either oppose or simply not approve the Transit Interchange, however a collaborative process remains a goal of all parties (and is memorialized in the Settlement Agreement) so such an outcome remains unlikely. Nevertheless, at this time the City Council appears headed toward a confrontation with Sound Transit and Metro.

You can view the video of the City Council meeting on Youtube. The Transit Interchange discussion begins at 5:07:00.