From DC Water:
“As part of the excavation work for DC Water’s Potomac River Tunnel Project, weekly controlled underground blasting operations at the West Potomac Park construction site will begin as early as next week and continue through February 2026. The site is located along the Potomac River at Ohio Drive and Independence Avenue Southwest. All streets and sidewalks will remain open during blasting events, with no restrictions on boats or watercraft in the river.
The blasting operations are part of constructing two mining shafts needed to begin tunneling. These shafts, approximately 103 feet deep, will be used to lower and launch two tunnel boring machines (TBMs). These machines will construct the 5.5-mile tunnel. One TBM will excavate north, boring through rock to the endpoint at Georgetown University’s entrance on Canal Road Northwest. The other will move south to the Joint-Base Anacostia Bolling (JBAB) site, where the Potomac River Tunnel connects with the Anacostia River Tunnel. The TBM excavating north, named Mary, will be delivered to the West Potomac Park site in the fall of 2025. The second TBM, called Emily, will be delivered in 2026.
What to Expect During Blasting Operations
Air horns will signal the start and completion of blasting operations.
Five minutes before the blast, an air horn will sound with three long signals.
One minute before the blast, the air horn will release five short signals.
The blast will detonate in a controlled manner.
Upon completion, one prolonged air horn signal will indicate the area is clear and safe. (more…)
