B\ THE CITY OF NASHUA “The Gate City’
"Division of Public Works
Wastewater Department
DATE: July 2, 2021
TO: Mayor James Donchess
FROM: David Boucher, Wastewater Superintendent
RE: Variable Frequency Drives, Wet Weather Facility
The Wet Weather Flow Treatment Facility (WWFTF) has four Raw Water Pumps
that move the wastewater and storm water through the WWFTF wet well and
into the rest of the Facility. These four pumps operate based on water level and
controlled by Variable Frequency Drives (VFDs).
One of the VFDs began to fault out about six weeks ago. We had all of them
looked at and it was determined they were obsolete, couldn’t be repaired, and all
would need replacement. We were proactive in getting quotes, hoping to get
them replaced before failure, however, we saw the first VFD fail completely on
June 30, which prevents us from using that Raw Water Pump. With three Raw
Water Pumps remaining, the WWFTF has no pump redundancy if the facility
receives flows greater than 40 MGD. With the three remaining VFDs in similar
condition and the potential to lose them at any moment, along with the 8-9 week
lead time, we are requesting an emergency PO in the amount of $39,980.00 to
M&M Electrical of Nashua, NH for the four VFDs needed to keep this critical
piece of infrastructure running. M&M Electrical of Nashua was the company
that provided us the lowest quote.
2 Sawmill Road * Nashua, New Hampshire 03060 + Phone (603) 589-3560 » Fax (603) 589-3474
