Timothy J. Clougherty
Public Works Director
Owen P. Friend-Gray, P.E.
Deputy Public Works Director
Robert J. Robinson, P.E.
Chief Sanitation Engineer
CITY OF MANCHESTER
Department of Public Works
Environmental Protection Division
Commission
Kathleen Sullivan, Chair
Arthur Gatzoulis, Co-Chair
Mark MacKenzie
Amber Nicole Cannan
Andre Parent
INVITATION FOR PREQUALIFICATION OF GENERAL CONTRACTORS
WASTEWATER TREATMENT PLANT
SECONDARY CLARIFIER REPAIRS
The City of Manchester owns and operates a wastewater treatment plant (WWTP) that is a 34 MGD
activated sludge process. The WWTP treats an average of 24 million gallons per day and was originally
constructed in 1976 with major upgrades in 1993 and 2016. The WWTP has three (3) secondary clarifiers.
Two of the clarifiers are original equipment from 1976 and the third is from a large facility upgrade in
1991. All three secondary clarifiers were upgraded in 2010. The clarifiers, after 16 years in service, have
experienced failures of the carbon steel fasteners, hardware and structural members that need replacement.
The Clarifier #2 48-inch influent slide gate has failed and cannot be operated and needs to be replaced. The
other two influent clarifier gates will also be replaced under this project. Also, the secondary clarifier 48-
inch crossover pipe has no means of isolation and the City wishes for new fabricated steel plates to be
installed at either end to block the pipe off. All of the work associated with the slide gate replacements and
blocking off the crossover pipe will require significant bypass pumping effort to maintain continuous flow
through the plant. Lastly the City also requires the plant water system isolation 14-inch plug valves to be
replaced. The estimated construction cost of this work is $2.75 million and construction duration is 300
calendar days.
PREQUALIFICATION
General contractors with extensive experience in wastewater and/or water treatment projects of a similar
size and scope are invited to submit prequalification packages for bidding on the City of Manchester’s
Wastewater Treatment Plant Secondary Clarifier Repairs Project. Questions should be directed to the
City’s engineer Underwood Engineers, Inc. care of Steve Smith at (603) 230-9898 or
ssmith@underwoodengineers.com. Sealed Prequalification Statements will be received at the Underwood
Engineers Concord office until 4:00 PM EST on Thursday, April 9, 2026. Prequalification statements
shall be addressed as follows: Prequalification Statement, Attn: Steve Smith, Underwood Engineers, Inc.,
99 North State Street, Concord, New Hampshire 03301.
ONLY PREQUALIFIED FIRMS WILL BE ALLOWED TO BID. Project will bid in April 2026 with a
bid opening in May 2026, and a Notice to Proceed issued for work to begin in August 2026. The right is
reserved to waive any informalities in or reject any or all prequalifying Contractors and to accept
prequalified Contractors that are deemed most favorable to the interest of the City of Manchester.
City of Manchester, NH
Department of Public Works
Environmental Protection Division
300 Winston Street, Manchester, NH 03103
(603) 624-6341
300 Winston Street • Manchester, New Hampshire 03103 • (603) 624-6595 • FAX: (603) 628-6234
E-mail: EPD@manchesternh.gov • Website: www.manchesternh.gov