Methuen Obayashi wins $360M Cemetery Brook drain tunnel contract
The City of Manchester announced that it has awarded the contract for its landmark Cemetery Brook Drain Tunnel Project to Methuen Obayashi Joint Venture – a nationally recognized civil construction partnership with extensive expertise in complex infrastructure and tunneling projects. The Cemetery Br

MANCHESTER, NH – The City of Manchester announced that it has awarded the contract for its landmark Cemetery Brook Drain Tunnel Project to Methuen Obayashi Joint Venture – a nationally recognized civil construction partnership with extensive expertise in complex infrastructure and tunneling projects. The Cemetery Brook Drain Tunnel Project is a large part of the City’s $500 million dollar program investing in the water quality of the Merrimack River over the next decade.
This approximately $360 million project is the largest public works project ever undertaken in the City of Manchester. In collaboration with the U.S. Environmental Protection Agency (EPA) and the New Hampshire Department of Environmental Services, the Cemetery Brook Drain Tunnel will transform the city’s drainage system, reduce combined sewer overflows (CSOs), and significantly improve the water quality of the Merrimack River, a critical natural resource serving over 600,000 residents.
About the Cemetery Brook Drain Tunnel Project:
- Contractor: Methuen Obayashi Joint Venture
- Construction Timeline: 2025–2028
- Tunnel Information:
o Length: 2.25 miles
o Diameter: 12 feet
o Depth: Up to 80 feet underground
o Route: From Queen City Avenue to Mammoth Road
Key Project Goals:
- Cleaner Water: By separating stormwater from wastewater, the tunnel will drastically
reduce pollutants discharged into the Merrimack River. - Reduced Flooding: The new system will alleviate basement backups and street
flooding—issues impacting many of our 115,000 residents. - Improved Public Health: The project will reduce Combined Sewer Overflows (CSOs)
and increase sewer system capacity during peak rainfall events.