GSA Annual Meeting, November 5-8, 2001

Paper No. 0
Presentation Time: 8:15 AM

KEYNOTE ADDRESS ON THE MWRA'S METROWEST WATER SUPPLY TUNNEL PROJECT


MCBRIDE, Michael J., Massachusetts Water Resources Authority, Charlestown Navy Yard, 100 first Ave, Boston, MA 02129, mmcbride@mwra.state.mass.us

The Massachusetts Water Resources Authority (MWRA) was created in 1985 as a public authority by an act of the Legislature to provide water and sewer services to 2.5 million people and more than 5,500 large industrial users in 61 metropolitan Boston communities. After spending most of the first ten years of existence concentrating on the wastewater side of the operation and the Boston Harbor Cleanup program, the MWRA Board of Directors in late 1995 voted to begin construction on a series of projects intended to update the MWRA water system. Those projects, which have been labeled the "Integrated Water Supply Improvement Program", include the 17.6 mile, 14-foot diameter hardrock MetroWest Water Supply Tunnel, the water treatment plants at Walnut Hill (405 mgd) and the Quabbin Reservoir (20 mgd), covered storage facilities, and various pipeline and aqueduct rehabilitation projects. The largest portion of the capital program is the 728 million-dollar MetroWest Water Supply Tunnel. In total, the entire program is estimated to cost 1.7 billion dollars. The MetroWest Water Supply Tunnel is a 17.6-mile aqueduct that has been bored through solid bedrock 200 to 500 feet below the communities of Southborough, Marlborough, Framingham, Wayland and Weston. Planning for this project began in 1988 and November 1996 marked the beginning of construction of the first of four tunnel contracts. The MetroWest Tunnel, when complete, will provide the second pipeline that has been delayed since the onset of WWII. After the MetroWest Tunnel is placed in service, the 60-year-old Hultman Aqueduct will be taken off line and rehabilitated providing metropolitan Boston with the redundancy that was planned for back in the 1940's. In October 2000, tunnel mining was completed. Currently only one Shaft remains to be excavated. Concrete and steel lining of the tunnel has been completed in two of the four tunnel headings and is currently on going in the other two. Upon completion of the tunnel lining (which is now about 50% complete) and the grouting operations, the shafts will be lined with concrete and steel, and the tunnel pressure tested and disinfected. The overall MetroWest tunnel program is over 75% complete and remains on the schedule set forth in 1996. The tunnel is also projected to be completed below the 728 million-dollar budget.