A direction has been set for building light rail to Lynnwood, and it’s up I-5.
Following a recommendation from Sound Transit planners, a panel of board members voted unanimously Thursday to send the same recommendation to the full board — that light rail follow the freeway from Northgate to the Lynnwood park-and-ride lot.
The other remaining choice was to build the rail line along Highway 99 through north Seattle and Shoreline, returning to I-5 in Mountlake Terrace and then to Lynnwood. Several other options, including bus rapid transit instead of the rail line, were eliminated earlier.
The full board could vote on the proposal as soon as next week.
Rail is not scheduled to reach Lynnwood until 2023, but a vote by the board will set in motion the environmental study process, according to a staff report.
Of the two routes, I-5 would have quicker travel times, more projected riders and lower construction costs than Highway 99, Sound Transit officials said recently.
The main advantage for a Highway 99 line was stronger economic development potential, planners said.
The cost for the Highway 99 line is estimated at $1.8 billion to $2.1 billion, while the cost for the I-5 line is pegged at $1.4 billion to $1.6 billion — a difference of $200 million to $700 million.
Travel time from Lynnwood to Northgate on an I-5 line is estimated at 14 minutes, compared with 18 minutes for the Highway 99 route, according to the staff report.
The number of daily riders in 2030 is estimated at 52,000 per day for I-5, 48,000 for Highway 99.
According to preliminary plans, the I-5 line would be part elevated and part at street level, running up the east side of the freeway from Northgate to Mountlake Terrace, then in the median to the Lynnwood Park-and Ride lot.
Stops would be located at N. 145th Street in Seattle, N. 185th Street in Shoreline and in Mountlake Terrace.
The final block-by-block details of where the rails would be built and location of the stops still has yet to be determined, Sound Transit spokesman Bruce Gray said.
The rail extension is part of an $18 billion plan approved by voters in 2008. The vote raised sales tax a half-cent per dollar in the Sound Transit service area in Snohomish, King and Pierce counties.
The plan as presented to voters assumed a route from Northgate along I-5 to the Lynnwood Transit Center at a cost of $1.2 billion to $1.4 billion.
Other possibilities were studied so the Sound Transit could show federal officials who dole out grant money that the agency has done its due diligence, officials have said.
Bill Sheets: 425-339-3439; firstname.lastname@example.org.