Sound Transit to start digging, probing along light rail line

East Link light rail’s finish date of 2023 might seem a ways off for commuters, but Bellevue residents can expect to see the project shift from the planning to more nuanced design phase of operations early this year.

East Link light rail’s finish date of 2023 might seem a ways off for commuters, but Bellevue residents can expect to see the project shift from the planning to more nuanced design phase of operations early this year.

Sound Transit will be collecting information on both public and private properties over the coming months, with fieldwork ranging from soil collection, to water level assessment and topography mapping.

“From a project perspective, it’s exciting that we’re moving out of the planning phase to more detailed design activity,” said Don Billen, East Link deputy project director. “We’re one step closer to construction.”

Fieldwork, says Billen, will help Sound Transit engineers create a detailed 3D model critical for project design. It will also help ST assess further cost-savings methods.

Activities fall into four main categories. Geotechnical exploration will involve the drilling of holes four to 12 inches in diameter, to allow for the collection of core samples from the ground. Surveying will involve the tracking of buildings, roads, utilities, trees, fences and other features. Though utility maps exist for the city, crews also will dig holes to determine accurately where underground utilities like water or sewer pipes are located. Those holes are later refilled.

Lastly, biologists will outline the city’s wetlands.

East Link alignment in Mercer Slough Nature Park will impact the edges of wetlands and wetland buffers require a stricter definition of what those limits are, says Billen. That process may include the digging of shallow holes by biologists.

While much of the fieldwork will be in public spaces, Sound Transit predicts work on some private properties along the alignment. ST staff are required to request right-of-entry permission from property owners, before doing so. Billen assured that outreach has already begun.

“Whether it’s public property or private, in advance, we’ll go out and notify nearby neighbors, whether they’re a business or residential, that this work is going to be occurring.”

Some cost-savings ideas – like shifting Bellevue Way west, or the relocation of a downtown station to Northeast Sixth Street or to the City Hall Plaza – have raised concerns about increased traffic in the Enatai neighborhood and reduced ridership in one of East Link’s most productive stations. But despite disagreements, Billen expects most residents will be responsive to the fieldwork: “Regardless of people’s opinions, there’s a general understanding that we’re getting more to inform our decision.”

Sound Transit expects the fieldwork to be relatively unobtrusive, except for projects on private property and the occasional road work. Last week, crews drilled on 110th Avenue in downtown Bellevue. Except for occupying a portion of the turn lane, traffic flowed north and south around the drill.

Activity will be concentrated on East Link alignment, in downtown Bellevue, along 112th and Bellevue Way, and in the Bel-Red corridor. Residents can expect to see, for instance, crews at South Bellevue Park-and-Ride, where light rail will be elevated on a bridge structure.

ST crews will drill holes in the vicinity at locations where columns will be placed in the ground. Information like soil samples can help crews understand what the ground is like in the area, and how deep and wide columns will need to be. Other work, on Bellevue Way and 112th, will focus on design efforts for greater cost efficiency.

An addendum will be published at the end of March, assessing cost-savings impacts, with a decision planned for April by the Sound Transit board. The city of Bellevue is partnering with ST on the evaluation. Major construction in Bellevue is expected to begin in mid-2015.