LYNNWOOD — Sound Transit staff has recommended prioritizing Lynnwood light rail service over an East Link “starter line” in recent board committee meetings.

Construction problems across Lake Washington along I-90 for the Link light rail track delayed the opening of the East Link extension between Redmond and Seattle’s Chinatown-International District. East Link originally was supposed to open this year, but is now eyed for 2025.

That shifting schedule has bumped into the operations plan for the Lynnwood Link extension. Construction of its four stations in Lynnwood, Mountlake Terrace and Shoreline and 8½ miles from Northgate to the Lynnwood Transit Center is on track to finish next year.

The Sound Transit board is weighing whether to open East Link or Lynnwood Link first. That decision is likely ahead as part of its 2024 service plan approval in October.

But recent staff recommendations favor Lynnwood.

Without access to the Operations and Maintenance Facility East in Bellevue, there isn’t enough room to store all of the additional light rail cars needed for the Lynnwood expansion at Sound Transit’s current base in Seattle.

Inadequate access to enough light rail cars would add time to its planned four-minute peak frequency and likely mean crowded trains between the Northgate and Westlake stations, Sound Transit director of system planning Brian de Place told the Rider Experience and Operations Committee last week.

“That’s what our forecasts are showing even with reduced post-pandemic demand,” de Place said.

Instead, light rail between Lynnwood and Seattle would see frequency similar to what runs now: every eight minutes during peak hours.

Last year Sound Transit board members, who are elected officials from the cities and counties within its district, asked staff to evaluate operating a “starter line” that just ran along the east side of Lake Washington until work finished so it could cross I-90.

Staff evaluations concluded that an East Link starter line was possible. They recommended an option with two-car trains running every 10 minutes and 14 hours each day. It would need 22 light rail cars, for which there is enough room and likely to be enough operators and maintenance workers.

Doing so also prioritizes the higher number of projected riders who would use light rail from stations in Lynnwood, Mountlake Terrace and Shoreline, de Place said.

The Lynnwood extension was projected to have up to 55,000 daily riders by 2026, Lynnwood Link executive project director Randy Harlow told the Mountlake Terrace City Council last week. About 5,000 were estimated to use the Mountlake Terrace station, which will have about 800 parking spots at the Mountlake Terrace Transit Center garage and nearby park and-ride lot.

Lynnwood Link is adding 34 vehicles with 70 seats, capacity for about 140 passengers, more standing room and larger windows to the fleet, Harlow said.

One of the existing problems is that Sound Transit has used more light rail vehicles than it initially projected needing for current service, deputy director of planning and integration Matt Sheldon told the committee in April. Longer running times, “gap trains” added to the schedule to maintain service frequency, lower reliability of the fleet’s vehicles and their need for maintenance have contributed to that, Sheldon said.

That’s meant 92 vehicles are deployed between Angle Lake and Northgate for peak service, where only 74 vehicles were planned originally.

“Our older fleet needs some retrofits and upgrades, and it’s taking more time to commission our newer Siemens fleet than planned,” Sheldon said.

The Operations and Maintenance Facility Central in Seattle has room for 104 vehicles. Another 20 can be stored overnight, with eight at Angle Lake and 12 at Northgate stations. But that leaves a gap of 21, Sheldon said.

Sound Transit has a few options, according to staff. They can run shorter trains (two or three cars instead of four) with eight-minute frequency, run four-car trains with lower peak frequency, or shorten trips from running the entire span of Angle Lake to Lynnwood and boost frequency in areas with highest demand, such as between Northgate and downtown Seattle.

To mitigate crowding, Sound Transit is working with other agencies such as Community Transit. Sound Transit could use a bus shuttle service, restore two Sounder North commuter train trips and restructure its Express bus routes.

Ben Watanabe: 425-339-3037; bwatanabe@heraldnet.com; Twitter: @benwatanabe.