North Dorchester Bay CSO Facilities Plan and Tunnel

 The 17-ft diameter storage tunnel of reinforced concrete segmental lining about 2.1 miles long, resulted in the elimination of CSO discharges to North Dorchester Bay.



  • Boston, Massachusetts, USA


  • Massachusetts Water Resource Authority

Project Status

  • Complete


  • Operations and Environmental Performance Award, The National Association of Clean Water Agencies, 2012

Key Numbers

Consolidation Conduits and        New Pipes
4,713 feet 4,713 feet
Depth of Mining Shaft
27.2 feet 27.2 feet
Length of Tunnel
2.1 miles 2.1 miles