Sound Transit announced today that work building a light trail tunnel from Roosevelt to Maple Leaf will begin as soon as this week.
Once construction begins, residents, local employees and drivers through the area will notice a series of short-term and long-term changes along First Avenue Northeast between Northeast 90th and 100th streets.
The immediate work will continue until January, and will include bicycle detours and making First Avenue a one-way street. Details are here.
Trees and shrubs will be removed, and jackhammers will cut through concrete.
Long-term construction includes launching a tunnel boring machine from the Maple Leaf portal to drill two light rail tunnels to Sound Transit’s Roosevelt station, on 12th Avenue Northeast near Northeast 65th Street.
Other machines will tunnel between the underground Roosevelt station and the University District and Husky Stadium stations. North from the Maple Leaf Portal, the trains will run above ground along Interstate 5 to the Northgate station.
All this is predicted to take about four years and is the biggest chunk of the $2.1 billion Northgate Link Extension, set to fully open in 2021.