Seeing that Sound Transit’s light rail and King County’s sewer upgrade were both scheduled to traverse the north end of Mercer Island over the next few years, the city decided to seize an opportunity to undertake another project: a master plan for Aubrey Davis Park, formerly known as the lid.

The 80-acre corridor of landscaped green spaces and pathways was developed for recreation and transportation during the expansion of Interstate 90 in the 1980s and 90s. In fact, most of it is located on top of the highway. The city named the park after Davis — a former mayor and driving force behind the creation of the facility — in 2013.

“Aubrey Davis Park is a bridge-to-bridge recreational and transportation facility that serves Bellevue, the Eastside and Seattle as well as Mercer Island with a multipurpose trail system, athletic fields, a boat launch and passive use park areas,” according to a 2016 memo from the city. “It is a regional park needing substantial planning services.”

Through agreements with the Washington State Department of Transportation, the city is responsible for maintaining 54 acres of the state-owned property in the park, and either owns or leases the remaining 26 acres.

But there are issues with the agreements, which says that permitting for projects is complicated, “maintenance” is not defined and capital needs were not addressed, according to the city. The deteriorating infrastructure is the biggest issue, and the impetus for the master plan.

The facilities are now 25 years old, creating problems: asphalt pathways are cracking, soils are depleted and portions of the trail are being used in ways that were not fully anticipated in the original design. Trail use has increased with population growth, and areas around the Park and Ride and the sports fields become congested when various users groups vie for the same space.

Trail users have requested signing, lighting and striping, and field users are asking for improvements in existing athletic facilities such as bathrooms, lighting and synthetic turf. All of this requires funds that the city currently doesn’t have. A master plan can help future city councils set capital budgets, and mobilize external investment through grants and other funding opportunities.

Last fall, Rep. Judy Clibborn and King County Councilmember Claudia Balducci hosted a meeting about the I-90 trail at Mercer Island City Hall, bringing together agency representatives from WSDOT, Sound Transit, King County, Mercer Island and Seattle, as well as the cycling community.

This year, city staff assisted Clibborn’s office in proposing a Washington state capital budget item for the Aubrey Davis Park Master Plan, which did not ultimately make it into the draft budget.

But the city still has $250,000 earmarked for the project over the next biennium. The city’s beautification fund will contribute $150,000, King County offered $50,000 to assist with funding the plan and the Sound Transit settlement will also reimburse the city up to $50,000 for the project. Sound Transit will also separately address the bike issue between 77th Avenue Southeast and 80th Avenue Southeast, according to the settlement.

An early draft design program will be presented to the public in various formats to solicit ideas and feedback. Certain user groups — such as those in arts, sports, cycling and boating — will be specifically contacted and encouraged to participate, as well as people who don’t live on the Island, but use the parks and trails.

Though the city is facing budget deficits and may need to push back a few capital projects, the city justifies the cost of the Aubrey Davis Park master plan for its potential to head off future conflicts.

“As illustration, the master plan for Luther Burbank Park was an extensive two year process. At the time, some people felt it was expensive and unnecessary,” according to the city memo. “However, that plan has been a workhorse for the past 10 years and continues to guide the maintenance and improvement of the park.”

The plan has supported $4 million of capital improvements, with the potential for $4 million more, and forms a common ground between the Parks and Recreation department and community interest groups, according to the city.

“There is little disagreement about the park going forward because consensus has been reached,” the memo states. “It also provides a solid basis for requesting grant funding, applying for permits and requiring agencies such as King County Metro to mitigate impacts of their work.”

Aubrey Davis Park is complicated by the ownership, maintenance and lease situation with WSDOT.

“This adds to the amount of planning and coordination needed to create the plan, but the payback will come when the adopted plan can be implemented with little further negotiation,” according to the memo.

There have been other issues with the park that have required extra funding. City staff recognized that certain issues could not wait to be addressed through the master plan and required expedited action prior to the expected conclusion of the planning process in 2019.

Some included pavement patching where roots have broken through the trail. In 2016, Parks and Recreation staff conducted an inventory of the pavement on the I-90 trail, and shared results with WSDOT staff. The parks department repaired the high priority sites on city-owned trail sections in 2017.

There are also issues with the visibility of the wooden bollards on the I-90 trail, raised by the 2015 case involving Susan Camicia. Camicia sustained severe injuries from a bicycle accident on the trail in 2006, after hitting one of the fixed wooden bollards. She became paralyzed, and received a settlement from the city of about $7 million.

In March 2016, Mercer Island selected Toole Design Group to provide design services for the trail. They evaluated the trail’s 196 bollards, and analyzed two sections of trail with high rates of pedestrian/bicycle incidents, recommending removal of all bollards and replacing them with alternative traffic control measures such as striping and signs. Parks staff removed 59 bollards on city-owned trail sections, completing the work in fall 2017, though 138 bollards remain on WSDOT-owned trail sections.

The city is anticipating working with and around the Sound Transit light rail station design and the North Mercer/Enatai sewer interceptor plan. Sound Transit is in the process of hiring a consultant for the design of light rail integration for Town Center and vicinity, and expects to conduct design, including public outreach, in 2018. Construction will be in 2019-2020 in conjunction with the station head houses.

The route of the sewer interceptor is the I-90 trail corridor from 81st Avenue Southeast eastward. King County has submitted 30 percent plans to city staff for review. SEPA environmental review will begin in the next few months and construction is expected to start in mid-2020.

The council discussed the master plan during a study session at its Nov. 21 meeting, and asked for more information about ongoing maintenance, levels of service in the park and numbers of bike commuters and other user groups, as well as the planned public engagement strategy. See www.mercergov.org/CouncilMeetings for more.