Differences Between Sewage Pumps and Grinder Pumps

A Sewage Ejector pump and Grinder pump are in-home lift stations that pump sewage from a lower level up to the height of an existing municipal sewer line.  Sometimes the sewage only needs to be lifted a short distance to reach a gavity line and sometimes the seweage needs to be pumped all the way to the vertial pipe near the street.  The height and distance determins the model of pump you will need.

While they may sound similar, sewage and grinder pumps operate differently to dispose raw sewage. Below, you will find information on how they differ. If you suspect an issue with either your sewage ejector pump or septic grinder pump, please do not hesitate to call your local licensed plumber.

 Sewage ejector pumps are designed to pump raw sewage from your home into a septic tank or gravity flow sewer main. For this reason, they can only pump to distances under 750 feet. However, a benefit of sewage ejector pumps is that they are built to move up to 200 gallons per minute of raw sewage. This is significantly higher than what can be pumped by septic grinder systems. In general, sewage ejector pumps are design to handle high volumes of sewage under low pressure. 

While sewage ejector pump systems and septic grinder pumps both pump raw sewage from your home to another destination, they accomplish this goal in different ways. For example, sewage ejector pumps don’t have grinding blades like their grinder pump counterparts. Instead they use impellers that spin to move raw sewage through the bottom of the pump. Pressure is then used to force the sewage into the discharge pipe.

 Septic grinder pumps are high pressure/ low volume systems. This means that they are better suited for moving low volumes of raw sewage over longer distances than sewage injector pumps. If you need sewage to be moved to your pressurized sewer main, a septic grinder pump will help you achieve this.

Within the septic grinder pump are blades that are used to grind the raw sewage into slurry before being discharged. From there, it is transported to the pressurized sewer main.

Septic grinder pumps should not be paired with septic tank systems because the slurry is so finely ground that it won’t separate from the liquid once inside the septic tank. This means that it won’t get sent on to the secondary system, which can destroy your underground leach field. 

 To figure out which pump is best for your home’s sewage pumping needs, it’s important to consider the volume of sewage you need to pump, its destination, and how far it has to travel to get there.

We recommend you install a grinder pump if you need to pump sewage to a pressurized sewer main. If you are pumping to a septic tank or a gravity flow sewer main, you are much better off with a sewage ejector pump.

Septic grinder pumps are also designed to pump ground sewage over thousands of feet, which is a farther distance than sewage ejector pumps can offer. The tradeoff is that grinder pumps can only pump low volumes of sewage. Sewage ejector pumps, on the other hand, can move high volumes of raw sewage (up to 200 gallons per minute) for distances under 750 feet.

When picking a sewage pump system for your home, it’s best to consult with a professional sewage pump plumber. A licensed plumber will be able to tell what pump is better suited for your household needs.