Drain and sewer installation on Bowdoin St.

Purpose

The Boston Water and Sewer Commission’s (BWSC) Dorchester Sewer Separation Project involves separating the combined sewer system within the project area described below. The purpose of this federal court-ordered project is to reduce pollution levels in Boston Harbor and Dorchester Bay by eliminating combined sewer overflows (CSOs).

Combined sewers, found in many older cities, carry both sanitary sewage and stormwater in the same pipe. During heavy rainstorms, the stormwater takes up the greater portion of the space in the pipe, at times exceeding the capacity of the system and causing the CSOs, which discharge to Boston Harbor, Dorchester Bay and tributaries. The Dorchester separation project is utilizing the existing “combined” sewer system and splitting it into two separate systems – one for sanitary flow and one for stormwater flow. At the end of the project, sanitary sewers will carry sewage to the Massachusetts Water Resources Authority’s (MWRA) Deer Island Wastewater Treatment Plant. Stormwater will discharge into Boston Harbor and Dorchester Bay. As a result, less stormwater will be sent to the treatment plant and Boston Harbor and its tributaries will no longer be subjected to the harmful effects of pollution from CSOs during heavy rainstorms.

Project Coordination and Construction Activity

BWSC is committed to working closely with the MBTA, MDC, Mayor’s Office, Boston Public Works Department, Boston Transportation Department, and other city departments and utilities to ensure the successful completion of this project. Effective project coordination will also help mitigate many of the short-term construction related impacts that will be associated with the project.

BWSC will adhere to all City Ordinances and regulations governing construction in public roadways. Whenever possible, BWSC will minimize temporary loss of on-street parking and will limit construction activity to not more than several days in front of any particular home or business. All dust, debris and excavate will be strictly controlled and monitored. In an effort to streamline and expedite all temporary or permanent roadway resurfacing activity, BWSC will complete all resurfacing work under its own contract rather than under a Boston Public Works Department resurfacing contract.

Community Relations Program

BWSC is committed to a proactive community relations program. The program is designed to keep residents, businesses and elected officials informed about the project by holding public meetings, placing notices in local newspapers, listing details of the project on BWSC’s web site and meeting with community groups and elected officials as requested. In addition, before construction begins, a notice will be sent in the mail announcing the work to be performed on the street. Any questions may be directed to Tom Bagley, Manager of Community Services, at (617) 989-7000.

The Dorchester Sewer Separation Project area is generally bounded in the north by Columbia Road; in the east by Dorchester Bay and Morrissey Boulevard; in the south by the Neponset River and Gallivan Boulevard; and in the west by Washington Street and Columbia Road. The project area is largely residential, with commercial districts along Dorchester Avenue, including Fields Corner and Uphams Corner, and along several other streets. Construction has or will occur in approximately 270 streets, including significant portions of major transportation routes such as Adams Street, Dorchester Avenue, Geneva Avenue, Hancock Street, and Neponset Avenue.

The project has been divided into eight sewer separation contracts. Sewer separation is being accomplished primarily through the installation of new storm drains and conversion of existing combined sewers into sanitary sewers. In addition, as needed, BWSC is rehabilitating or replacing water mains and sanitary sewers within the project area.

BWSC and MWRA 
Agreement and Costs

The Dorchester Sewer Separation Project is mandated by a federal court order as part of the Boston Harbor Project. Because BWSC has extensive experience in managing sewer separation projects and is well equipped to complete these projects, MWRA asked BWSC to implement the separation project. The estimated total construction cost of the Dorchester Sewer Separation Project, and related improvements to BWSC’s facilities, is expected to be $141.5 million.

Under the provisions of the agreement between MWRA and BWSC, it is anticipated that the MWRA will be responsible for approximately $117.0 million of eligible construction costs. The remainder will be funded by BWSC through its Capital Improvement Program (CIP) for additional water and sewer system improvements being completed concurrently with this project. There are no funding provisions for new sidewalks, curbing or lighting; however, any roads and sidewalks disturbed by separation construction will be restored by BWSC upon completion of the project.