The Federal Way Link extension is one of four Sound Transit projects facing delays due to construction issues, according to a new report provided Thursday to the Sound Transit Board System Expansion Committee.
These delays push back the scheduled opening dates for the East Link, Lynnwood, Federal Way and Downtown Redmond Link Extension routes. According to Sound Transit, signs of possible delays have been tracked since April due to nationwide issues, but also particular challenges at individual sites.
In Federal Way, an “unexpected” ground instability issue for the project may result in a redesign of the section of road in Kent adjacent to I-5 and 259th Place South. Sound Transit said it was too early to tell how long the construction delay will last, but expects the Federal Way Link extension to open in 2025 instead of the scheduled opening in late 2024.
Last month, about 200 linear feet of fill slid down about nine feet, requiring an approximately three-day precautionary lane closure on southbound I-5. While the grade is temporarily stabilized, Sound Transit and design-build contractor, Kiewit, are working with the Washington State Department of Transportation to develop permanent design solutions. This involves treating a layer of liquefiable soil that has been identified quite deep below the light rail route.
Another aspect impacting the delayed Federal Way Link opening schedule is traffic mitigation commitments.
Traffic mitigation is an environmental requirement to reduce impacts from operating the extension and includes 10 separate sites for intersection improvements, according to a memo from Sound Transit.
Improvements are expected to be completed prior to the opening of the Federal Way Link road. Risks include delays or legal challenges to possession of the right-of-way, as well as use and acquisition preventing timely acquisition of the right-of-way. Local jurisdictions requiring additional design changes and delays in necessary utility moves are also threatening the planned opening schedule.
East side projects
The east and west sides of the I-90 floating bridge are also facing delays due to issues with the cast-in-place concrete plinths supporting the tracks. Problems were identified with the mortar pads, rebar placements and rail fixings, which the project contractor agreed to resolve by recasting the plinths to ensure the long term reliability and safety of the extension, according to Sound Transit. A forensic engineering firm determined that the precast concrete blocks supporting the tracks on the bridge did not need to be replaced, according to a preliminary investigation carried out in July and August.
For the East Link route, Sound Transit’s original plan was to open in mid-2023. Now the agency estimates the project will be delayed for at least a year due to construction issues.
As new project timelines are still being assessed, the agency expects construction completion of the Lynnwood and Redmond projects to be delayed four to six months beyond the scheduled opening in mid-2024. This slightly exceeds the delay of more than four months caused by the concrete delivery strike that ended in April, according to Sound Transit.
The delay in the link extension to downtown Redmond is also tied to challenges around staffing and supply chain issues, managing potential design changes as lessons are learned on d other projects and electrical connection issues.
Sound Transit is focused on addressing delay risks and opening projects without changing the order in which they go into operation — East Link followed by Lynnwood, Federal Way then Redmond, according to the memo.
The agency has action plans in place to address and resolve the risks of project delays.
“In addition, staff have implemented changes supporting intensified inspections and monitoring of contractor work,” according to an agency press release.
This includes conducting a programmatic risk assessment to analyze project implications.
“Because each project is part of a system, we need to look at the current status of projects at a programmatic level, focusing on the details of project sequencing,” the agency said.
Programmatic analysis is “critical” because after construction, light rail segments must be activated sequentially within appropriate safety and personnel parameters with up to six months of testing before each segment is activated.