Grinder Pump Information

If your sewer is backed up but your grinder pump alarm is not going off (and you have electricity at your house), then your issue is likely a plumbing issue in the pipe before the pump - call a plumber or a drain company.  Please call F.R. Mahony, the grinder pump manufacturer's representative, (508) 765-0051, if you are having an issue with your LPSSA residential grinder pump.  

Properties in the low pressure portion of the sewer system require a grinder pump unit. In addition, grinder pumps were needed for some properties which, due to their elevation, have to pump to the Town's gravity sewer system.

The Town engaged in a competitive bid process in order to procure high quality, standardized pump systems with a five-year warranty. Environment One Corporation (E/One) was the successful bidder in that process. The Town provided one E/One grinder pump unit to each single-family residential property that required a grinder pump, at no charge. The property owner will own the pump unit and was responsible for its’ installation. 

Owners of non-residential properties and of multi-family residential properties worked with an engineering firm to design a connection plan for their property; pumps needed for these connections were not provided by the Town.

The Board of Selectmen approved a Grinder Pump Policy (PDF) on May 16, 2016.  The Selectmen's Policy states, among other commitments, that the Town will provide for maintenance of the pumps after the 5-year warranty has expired. 

Each property owner coordinated with their plumber regarding grinder pump installation. Training for plumbers and contractors on grinder pump installation was held twice in 2016 and once in 2017. The Town did not certify or approve plumbers or contractors, but the Town strongly recommended that property owners that needed grinder pumps contract with plumbers that attended the E/One installer training.  The work was required to be overseen by a plumber licensed in the state of Massachusetts.

When the property owner’s representative picked up the grinder pump, they were required to provide a form signed by the property owner, agreeing to transfer of pump unit ownership from the Town to the property owner and to a right of entry for the Town or its agent to enter onto the property to service the pump.

Types of Grinder Pumps


There were 3 types of grinder pumps made available by the Town for the LPSSA: outdoor grinder pump, flood zone outdoor grinder pump and indoor grinder pump.

Outdoor Grinder Pump


This unit has an automatic internal vent system housed within the cover. This unit is intended for installations where the pump system cover will not be subject to flood conditions.

Flood Zone Outdoor Grinder Pump


This unit is exactly the same as the standard Outdoor Unit except that is has a flood proof cover and is provided with an orifice for connecting an external PVC vent pipe. The flood zone unit is intended for installations where the pump system cover may be subject to flood conditions.
  • Map Showing Low Pressure Parcels Located in the Flood Zone (PDF): This map shows in bold outline the low pressure properties which are located at least in part in the AE flood zone (flood zone shown in bright blue). If the grinder pump is located within the AE flood zone, then a flood zone pump unit was to be specified. If the pump was to be outside the AE flood zone, then it was up to the property owner and their plumber whether or not to specify a flood zone pump unit. Some properties are only partially in the flood zone; if the pump could be located outside the AE zone footprint, then it was not required to be a flood zone pump.
  • Flood Zone Outdoor Grinder Pump Detail Sheet (PDF): The flood zone outdoor unit is exactly the same as the standard outdoor unit except that it is has a flood proof cover and is provided with an orifice for connecting an external PVC vent pipe, as shown on the attached detail sheet. The user instructions are the same for the flood zone outdoor unit as for the standard outdoor unit.

Indoor Grinder Pump


It was recommended that this unit be considered only when installation of one of the other two pump unit types is not feasible. It was not advised that these pumps be installed in a finished basement. If maintenance is needed on an indoor grinder pump unit, the service person will need access to the basement and the maintenance will be performed in the home's basement.

Other Information Pertinent to the Grinder Pumps