The decommissioning of the Battery Street Tunnel enters a new phase next week, when the contractor, Kiewit, begins to fill the tunnel from the surface of Battery Street.
Crews have already cleaned the tunnel of decades’ worth of automobile exhaust and removed the tunnel’s mechanical and electrical systems. They will continue to install sewer lines and conduct other utility work. But starting as soon as next week, the contractor will begin trucking in concrete rubble from the viaduct demolition and sending it into the tunnel using funnels on Battery Street. Crews removed steel rebar from the rubble and crushed the concrete into baseball-sized pieces.
Caption: The ledge at left is fill material already brought in by truck and compacted to support a new sewer line that will be placed on top. The yellow chute at right is part of the tunnel ventilation system to keep fresh air circulating for workers.
Inside the tunnel, crews will compact the fill using a vibratory roller. The work will last at least three months as crews fill up to about seven feet from the top of the tunnel.
Effects of construction
One lane or sidewalk at a time will be closed on Battery Street between First Avenue and Sixth Avenue, depending on where crews are filling on a given day. The compaction happening inside the tunnel causes vibrations that may be felt on the surface and in adjacent buildings.
Details of the work and what to expect in May and June:
- Battery Street reduced to one lane at various locations, 6:30 a.m. – 3 p.m. Monday – Friday.
- Trucks dumping fill material through a specialized funnel on Battery Street, 6:30 a.m. – 3 p.m. Monday – Friday.
- Vibration from compaction work inside the tunnel 6:30 a.m. – 5:30 p.m. Monday – Friday.
- Funnels and other construction equipment stored on Battery Street when not in use.
People living, working or traveling near the work may see and feel increased noise, dust and vibration during the work hours (weekdays 6:30 a.m. – 5:30 p.m.). The filling operation ends at 3 p.m. to keep Battery Street fully open during the evening commute.
Caption: Side-dumping trucks like the one above will deposit fill into funnels on Battery Street.
The Battery Street Tunnel, like the Alaskan Way Viaduct, is seismically vulnerable. Decommissioning it improves surface mobility by allowing three blocks of Seventh Avenue North (formerly Aurora Avenue North) to be rebuilt into a two-way surface street with four-way intersections and bus lanes. For a weekly email update on Battery Street Tunnel construction progress, join our email list.