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Can The Washing Machine Drain Into A Sewage Pump?

Some homes have a sewage pump that directs wastewater into the septic tank. Can the dirty water from the washing machine drain into this as well? We've looked into this and here's what our research uncovered. 

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The washing machine can drain into the sewage pump but this isn't recommended as it can cause water contamination and damage to the septic tank. When this happens, your family's health is at risk. It also has a negative effect on the plants and wildlife around you.  

Continue reading to learn more about why your washing machine shouldn't drain into a sewage pump and where it should be draining instead. We'll also answer if your washing machine can drain into a sump pump and how you'll know where this appliance currently drains. Let's get down to business!

plumber repairing washing machine working man, Can The Washing Machine Drain Into A Sewage Pump?

Washing Machine Draining To Sewage Pump

Washing machines are essential in every home. They get our laundry clean and dry without taking up so much of our time.

A washing machine works by filling the tub with water and mixing it with detergent. Then, the machine will use an agitator, impeller, or rotating drum to remove the dirt from the fabric. After this, it will rinse off the soap and dispense the dirty water out of the unit.

A washing machine usually drains water out of the tub at least 2 to 3 times through its wash and rinse cycle. It consumes an average of 30 to 35 gallons of water per laundry load. And the used and dirty water needs to go somewhere so that it won't go back inside the machine or flood the laundry area. Therein lies our question. What does the wastewater drain into?

plumber repairing washing machine working

Your home plumbing system determines where your washing machine drains. 

For those connected to the municipal sewer system, your washing machine's drain hose is connected to the sewer line. This is also where the wastes from the sinks, showers, and toilets go. It is considered the main sewer line that leads all the way to the treatment plant. This kind of plumbing system is commonly found in urban and suburban areas.

On the other hand, some homes have septic tanks because they aren't served by a municipal sewer system due to their property's terrain or location. This is common in rural areas.

Instead, they use a sewage pump as a channel for untreated wastewater as it goes to the septic tank. This is where they dispose of all their wastewater and have it treated before it is released into the drainfield which is buried underground.

The septic tank ensures that your drinking water isn't contaminated by wastewater. Solid waste is separated from wastewater, partially decomposed by the bacteria inside the tank, and later on, the remaining sludge and scum are pumped out by a professional.

The Effect of Washing Machines on Septic Tanks 

Technically speaking, the washing machine can drain into a sewage pump. However, it would depend on the capacity and condition of the septic tank. 

The septic tank's drainfield capacity is limited when it comes to handling greywater or waste from the washing machine, shower, and sink. Considering the amount of wastewater from the washing machine per laundry load and your frequency of usage, the septic tank's holding capacity might be exceeded.  

When this happens, there is a high probability of water contamination since the waste cannot be treated efficiently and effectively. It can also cause the total breakdown of the septic tank system.

This type of wastewater can cause blockages in the septic tank. It can also lead to wastewater flowing out of the tank prematurely before it has been treated properly. This means that you've got untreated wastewater draining on your property.

There are also concerns about the water coming out from the washing machine containing a high concentration of chemicals from the detergent, surfactants, bleach, and other cleaning agents used.

These are harmful especially when they get mixed up with the groundwater and later on when they're disposed of on the ground soil. Contaminated water will have an adverse effect on the lives of plants and wildlife.

As such, it isn't recommended to have the washing machine drain into the sewage pump and into the septic tank. It will potentially contaminate and damage the sanitary sewage system. This can put not just your family's health at risk but also the plants and wildlife around you.

Can a washing machine drain into a sump pump?

washing machine drain clean close open

This is also one of the most common questions homeowners ask when considering washing machine drainage options. 

A sump pump is usually installed underneath the basement floor. It helps pump water out of the house to prevent flooding in the basement and spare you from the costs and hassles of water damage. It is activated once the water reaches a critical level and shuts off once the water has been pumped out and falls below the indicated level. 

A sump pump is part of a basement waterproofing system. It comes in handy during stormy weather especially if you're living in a low-lying area.

If you drain your washing machine into the sump pump, there'll be a surge of dirty water each time you use your appliance. The machine consumes roughly around 30 gallons for each load. If all of this is drained directly to the sump pump, it might not be able to handle the fast rate at which the appliance dumps its wastewater.

The water also contains chemicals, lint, and other dirt that can potentially damage the sump pump. It can clog its pipes which can result in a bigger problem in your basement.

Since you probably use your washing machine frequently, there is also the issue of wear and tear. Your sump pump will have to work every time you use your appliance to divert water away from your home.

As such, it is not recommended to drain your washing machine into the sump pump.

Where should wastewater from the washing machine drain then?

hand plumber holding broken flexible drain

If you have a septic system at home, draining the washing machine into the sewer line can cause contamination problems. The solution here is for you to have a separate greywater system. This is where the wastewater from your washing machine is supposed to go.

It has its own dedicated line separate from the sewer system to avoid complications. It is a dry well located underground and should be installed at least 4 ft away from your foundation. With the help of filtration technology, gravel, and other elements, wastewater from the washing machine is filtered before it is released into the soil.

This makes it safer for the environment and can even be used to irrigate your lawn and garden.

By draining your washing machine in the greywater system, the septic tank won't overflow or overwork itself. It will prevent flooding or pooling of wastewater in your property and make your septic tank last longer.

How do you know where your washing machine drains?

Now that you know this important information, it's understandable that you'd want to know where your washing machine currently drains. You will need to seek the assistance of a professional plumber to check where the pipes are connected. A plumber will help you understand where your washing machine drains and if it is the ideal solution for your home.

There is also free assistance offered by the state for those who plan to do any digging on their property. Just call 811, give them your address, and inform them of the kind of home improvement project you need to work on. They'll send someone over to mark out the utility lines installed underground so that they won't be damaged during your digging.

But if your home is serviced by a municipal sewer system, there's no need to hire a plumber to let you know where your washing machine drains. It will flow to your main sewer line where all your wastewater drains into.

This service is only recommended for those homes with septic tanks so that they can confirm if the washing machine is draining into an independent greywater system. After all, it's better safe than sorry, especially since it concerns health and sanitation.

Final Thoughts

plumber repairing washing machine working man

You should know where your washing machine drains its wastewater. It shouldn't compromise your family's health as well as the other living things around you. Make sure it drains into the main sewer line if you're connected to the municipal sewer system or to a greywater system if you use a septic tank at home.

Feel free to visit the following links for some related reading:

How To Run A Washing Machine Drain Outside Into The Yard?

Why Does My Washing Machine Smell Like Sewage?