First stage of Battery Street Tunnel filling wraps up this summer
If you’ve traveled along Battery Street recently, you may have noticed large metal containers sitting on the side of the road. These specialized hoppers are placed above the Battery Street Tunnel’s ventilation grates, and trucks pour crushed concrete rubble through them into the closed tunnel beneath. (Have you seen our video of this work in action?)
The contractor Kiewit is filling the Battery Street Tunnel with crushed concrete salvaged from the demolition of the Alaskan Way Viaduct. Working from Denny Way southwest toward First Avenue, crews spend several weeks per block filling the tunnel beneath up to about seven feet from the ceiling.
Kiewit’s current Battery Street Tunnel working hours are 6 a.m. – 6:30 p.m. Monday – Friday, with the filling from the surface stopping by 3 p.m.
Compacting the rubble with vibration
Inside the tunnel, Kiewit spreads the fill out along the tunnel’s old roadways and compacts it with vibratory rollers. The rollers produce vibration that may be felt in adjacent buildings. The amount of vibration felt in a nearby building will vary depending on the building’s distance from the active work area and what type of work the crews are performing. Crews may spread and compact the crushed concrete up to several blocks away from where the fill is poured into the tunnel.
Below is the current schedule for the filling and vibratory work. The dates may change somewhat based on progress:
Drivers on Battery Street should expect one lane to be closed 6 a.m. – 3 p.m. while crews are filling the tunnel beneath that block. There will be trucks, hoppers and crews working in that closed lane. Kiewit is also working with local utility companies to install utilities within the tunnel, which sometimes requires short-term lane or sidewalk closures on Battery Street or adjacent side streets. After the filling is complete, crews will return to repair the street grates and any damaged sidewalks or roadway.
What comes next
The crushed concrete work will wrap up this summer, filling up the tunnel to about seven feet from its ceiling. The top seven feet will be filled with a low-density cellular concrete pumped into the tunnel from the surface. This final tunnel fill work is scheduled for early 2020.
Later phases of work will remove the grates from Battery Street’s roadway and sidewalks, and repair the holes. Crews will also install new street lighting, curb ramps and other pedestrian improvements. The project is expected to be complete by mid-2020. We provide weekly construction updates about the Battery Street Tunnel project via our construction email list. You can also contact the project by email, email@example.com, or by calling the 24/7 construction hotline at 1-888-298-5463.