To:
From:
Re:
B. Motion:
Attachments:
Discussion:
City of Nashua, Public Works Division
Board of Public Works Meeting Date: February 28, 2019
David L. Boucher, Superintendent
Wastewater Department
Wet Weather Facility Screening Upgrade — Design and Bidding Phase
To approve the contract with Wright Pierce for professional design and bidding
phase services for the Wet Weather Facility Screening Upgrade in an amount
not to exceed $178,000. Funding will be through: Department: 169 -
Wastewater; Fund: Wastewater; Activity: Wet Weather Upgrade.
Wright Pierce Proposal
The Wet Weather Facility located at 2 Sawmill Road in Nashua is designed to
treat flows at the wastewater facility above 50 million gallons per day. Over
the years, the facility has experience issues with its two influent screens. Parts
of the screen fields have become bowed allowing large material to pass
through and clog pumps within the Wet Weather Facility. Another issue is that
the rake mechanisms do not remove debris properly from the screen field
allowing flow to back-up into the interceptor creating other issues and causing
the Wet Weather Facility to be ineffective. Several interim solutions have
been tried to correct the issues with little success.
Wright Pierce was hired to do a preliminary investigation of the Wet Weather
screening area and determined new screens are needed. We are ready to
proceed with the design phase of this project and have asked Wright Pierce to
continue with this effort.
Wright Pierce has done a number of projects at the wastewater facility since
2012 in a satisfactory manner. There cost of $178,000 is reasonable for the
scope of work involved. The construction cost to upgrade the screens will be
determined by Wright Pierce, but are estimated to cost around 2.2 million
dollars. Their cost is less than 10% of the estimated construction cost; which is
very reasonable for design and bidding services.
