Celebrating 65 Years of "No Problem" Service


Blog posts of '2020' 'March'

To Grind Or Not To Grind …

Many of you might have seen a recent Facebook post from the Milwaukee Metropolitan Sewage District showing a photo of what happens to “flushable” wipes after they’re flushed. Looking at that mess at their pumping station, you see it’s quite the clog.

The recommendation is not to flush those “flushable” wipes, but people won’t stop doing it until perhaps it hits them in the wallet when a professional needs to unclog a lateral pipe or pump system.

Is there a solution to this? Depends on the consumer, what is thrown into the toilet, and equipment installed.

Some homeowners (and professionals too) make the incorrect assumption that a grinder pump will alleviate the problem. With their powerful cutting blades, grinder pumps break down household waste and help alleviate potential clogs. But even so, the only items that should be going down the drains are water, regular toilet paper, and human waste, better known as the three P’s (pee, paper, and poop).

While the industry is making advances in grinder pump cutters and centrifugal pumps with vortex impellers, they still are not able to remove a large volume of the wipes from the sewer system, resulting in the homeowner’s pumping system to clog.

So where and why are grinder pumps used? Grinder pumps are typically used when pumping from a residence to a low pressurized sewer main, typically required when the gravity sewer is a long distance from the residence or there is a dramatically high vertical lift. Grinder pumps macerate the sewage, reduce it to a slurry, and then pump it through diameter pipe as small as 1-1/4 in. The most common pump is rated 2 HP, which provides high pressure/low volumes of sewage pushing the waste over longer distances, sometimes thousands of feet.

Some grinder systems are installed with outdoor lift stations or indoors using a large fiberglass basin with a sealed cover, vent, and discharge, along with a check and ball valve. Most grinder pumps have a control panel with a built-in alarm because they are serving the whole house.

One of our popular models for domestic sewage is the IGP Series Grinder Pump from Franklin Electric, which operate across 208-230V ranges in one model. The GPA (automatic) and GPM (manual) versions’ motors and construction are designed to handle the demands of low-pressure sewage applications, grinding at 414,000 cuts per minute. They incorporate a non-clogging impeller staged for efficient pumping of the slurry with a shut-off head of 130 feet or 200 feet for the dual staged pump. Another good centrifugal based 2HP grinder pump option to consider is the OGP Series from Barnes.

As stated above, grinder pumps are designed to pump to a pressurized sewer main. They are not recommended for a septic tank, however there is an exception if the system is designed appropriately. If the special design is not completed correctly, the fineness of the slurry won’t easily separate from the liquid and therefore won’t get passed on to the secondary system. The result will be a ruined subsurface leaching field. Contact your trusted septic contractor to further discuss this option.

JMI Pump Systems has a large selection of grinder and sewage pumps to choose from. If you are not sure what your application calls for, we will be glad to assist. We are happy to visit a job site to help design, troubleshoot, and even assist with a new installation. For more information, contact us at 800-234-5490 or sales@jmipumps.com.