Grinder Pump Information

Understanding Your Grinder Pump Sewer SystemGrinder Pump

A grinder pump sewer system is used in locations where your home's wastewater cannot simply flow downwards by gravity to reach the main public sewer line. This often happens when your property is situated at a lower elevation than the main sewer. Instead of gravity, this system uses a pump to move the wastewater uphill or horizontally.

Wastewater from all your home's drains, such as toilets, showers, and washing machines, flows into a holding tank, which is typically buried outdoors on your property. When the water level inside this tank reaches a certain point, the grinder pump, located within the tank, automatically turns on. This pump is equipped with a grinding mechanism that breaks down the waste into a fine mixture or slurry, much like a powerful garbage disposal. The pump then forces this ground-up wastewater through a special pressure pipe that connects to the public sewer system or a septic tank. The pump only runs as long as needed, usually about one or two minutes, until the water level in the tank drops to a lower preset point, at which time it switches off automatically.

The complete system consists of several key parts: the holding tank, the pump with its grinding mechanism and level controls, various pipes and valves, and an electrical control panel that manages the pump's operation and is connected to your home's electricity.

How to Care for Your Grinder Pump System

Properly maintaining your residential grinder pump system is crucial for its efficient and reliable operation over many years. As the homeowner, you are responsible for ensuring both the routine inspection and maintenance of the grinder system and the plumbing within your home. Although some pumps can last for a long time before needing service, scheduling annual inspections is recommended.

Here are some important ways to care for your grinder pump system:

  • Conserve Water: Using water efficiently in your home helps reduce the amount of wastewater entering the grinder system. Less water flowing into the tank means the pump activates less frequently. Fixing leaks, even small ones like dripping faucets or running toilets, can conserve a significant amount of water daily or yearly, lessening the workload on your pump.
  • Be Mindful of What You Flush: Never flush certain items down toilets, sinks, showers, or put them into garbage disposals that connect to the system, as they can clog or damage the grinder pump. Items to avoid flushing include: 
    • Diapers, feminine hygiene products, condoms, and any type of wipes (even those labeled "flushable"). Disposable wipes, specifically, are known to cause problems in sewer systems.
    • Fats, oils, grease, or grit (often referred to as FOGG).
    • Dental floss, cotton swabs, cigarette butts, coffee grounds, cat litter, and paper towels. These items should always be placed in a garbage can instead. Additionally, do not flush household chemicals like gasoline, oil, pesticides, antifreeze, or paint. These dangerous materials should be taken to a local hazardous materials handling or recycling station for safe and legal disposal. In general, only human waste and toilet paper should be flushed.
  • Limit Garbage Disposal Use: Using your garbage disposal increases the amount of solid food waste that goes into the grinder pump tank. This requires the pump to run more often to grind these solids. Increased pump usage can lead to more frequent maintenance needs and potentially higher operating costs. It's better to dispose of food waste in your trash can whenever possible.
  • Prevent Rainwater Entry: Make sure that rain drains or storm drains do not flow towards your grinder system's location. Excess rainwater entering the tank reduces the storage capacity available for wastewater and increases how often the pump has to run, adding unnecessary costs and volume for the treatment plant.
  • Be Familiar with Your System's Location and Controls: 
    • Find and label the circuit breaker in your home's electrical panel that provides power to your grinder pump system. This prevents you from accidentally turning off its power. You are responsible for ensuring the system has electric power.
    • Know where the grey electrical service control panel for your system is located outside your building, but do not attempt to open or tamper with it. If there is a problem with the system, you should call a qualified contractor.
    • Be aware of your specific pump system's limited storage capacity (ranging from 30 to several hundred gallons depending on the tank size). This knowledge helps you avoid spills or backups, especially during power outages.
Be careful what you flush

What to Do in Case of Power Outage or System Alarm

  • If there is a power failure, you must significantly limit your water usage because the tank's storage capacity is limited. Avoid using water for activities like showering or washing clothes.
  • If your grinder system has a problem, an audible alarm will sound, and a red light will illuminate on the control box. When this happens, immediately limit your water usage. You can typically silence the loud buzzer by pressing a button on the alarm panel, but the indicator light will likely remain on. Wait for about an hour; if the light turns off, the system may have cleared itself. However, if the light is still on after an hour, you must call for service right away to prevent potential sewer spills or backups. When calling for service, be prepared to provide your name, home address, and telephone number.
  • It is critical that you do not attempt to repair the grinder pump unit yourself. Always call a qualified service provider or the number provided for assistance. Make sure the service person can easily and safely access the pump station for repairs.

Proper Property Care Around the System

  • Do not touch the valves associated with the system.
  • Do not turn off the power to the pump unless you are dealing with a broken discharge pipe.
  • Do not block the vent on the pump station or cover the lid of the tank.
  • Keep the area around the pump station clear and accessible at all times by removing plant growth or other debris.
  • Be cautious when digging in your yard near the location of the pump station or the buried discharge pipe. If you accidentally break a pipeline, call for service.
  • If you are planning major home modifications, such as adding a spa, an oversized tub, or extending your house over or near the pump unit or discharge pipe, you should contact your system provider (like E/One or a local distributor mentioned in one source) beforehand.
  • If you plan to be away on a long vacation, it is suggested that you flush the system before you leave. You can do this by running clean water into a drain until the pump activates, then turn off the water and allow the pump to run until it shuts off.
  • Recognize Signs of Potential Issues: Noticeable wet spots around the pumping unit or the discharge pipe (when it hasn't been raining) or persistent odors could indicate a leak or other problem. If you see these, contact the service number. If the alarm activates specifically when it rains, it might mean rainwater is getting into and overloading your system; you should contact a plumber to investigate this issue.

E/One Grinder Pump Stations

Groton Utilities (GU) installs E/One Grinder Pump stations in situations where a standard gravity sewer system is ineffective. The grinder pump forces the sewerage to higher grades where it can then flow by gravity.  GU owns and operates the grinder pumps, which are located on private property. GU maintains these with annual maintenance while also responding to issues when they arise.

E/One Grinder Pump Station Owners Guide

Contact Groton Utilities directly if you experience grinder pump issues.

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