Why Is My Basement Floor Drain Backing Up? Causes and Fixes

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Last year, I had the unfortunate experience of my basement drain backing up. When I returned home after being out of town for two weeks, I discovered a flooded basement and an awful smell.

Turns out, a huge snowstorm followed by an increase in temperature led to the situation. If I had not been lucky enough to return after a couple of weeks, I could have faced much worse.

If your drain is backed up, it’s important to deal with the situation promptly and effectively. Otherwise, you might find yourself dealing with property damage, health hazards, and inflated repair costs.

basement floor drain backing up

Causes of Basement Floor Drain Backups

There are many reasons why your basement floor drain might back up. You might think it’s to do with the actual clogs and defective pipes of the sewer line, but it’s a bit more complex than that. Remember to always consult with a plumber before trying to fix anything.

Now, let’s examine some of the most common causes:

Main Sewer Line Clogs

When first discovering a backed up drain, it’s important to determine whether the cause is waste coming from your own house, or from the public sewer system. This will help you solve the problem.

Sometimes, the cause of a backed up drain can be from issues with main sewer line clogs. Things like grease buildup, tree roots, collapsed pipes, and overwhelmed municipal systems due to heavy rain or snowmelt can all affect the pipes. 

If water rises in the public sewer system above the level that your basement sewer drain is sitting at, it can therefore cause a backflow leading into your property.

Tree Root Intrusion

In older homes, you might find that your pipes are made from materials such as clay or cast iron. This makes them more susceptible to wandering tree roots.

Tree roots are naturally attracted to the moisture and nutrients found in sewer pipes. This can lead to them finding their way in through small cracks or holes. They then grow and expand within the pipe, effectively creating a block that leads to a blockage.

Deteriorated or Broken Pipes

Another common cause is related to how old your pipes are. Older pipes might be weaker due to their age, as well as the ground shifting in your area. This can cause the pipes to crack, collapse, or misalign underneath your house, resulting in a backed up drain.

Blockages in Drain Lines

It’s important to look at your own household waste when determining the cause of the backup. Flushing items that aren’t meant for toilets can cause sewer line blockages and lead to floor drain overflow. 

Things like hair, soap scum, and grease are meant to be placed in the rubbish bin, not down the toilet. All this accumulated debris creates a barrier, preventing water from flowing as it should do through your pipes.

Heavy Rainfall and Flooding

Frequent snowstorms and heavy rainfall can cause municipal sewer systems to overflow. All this excess water needs to go somewhere, leading it to accumulating in residential plumbing systems, with basements being the worst offender.

Poorly Installed Floor Drains

If your floor drain wasn’t installed properly, you find yourself dealing with some backup problems. One of the most common issues is drain being installed on an improper slope, where the pipe is not angled correctly towards the sewer line. This can lead to stagnating water or for it to flow back into the basement.

Another issue is a missing or faulty trap. If the trap isn’t installed properly, it can allow sewer gasses to enter the basement. It can also not prevent backflow during heavy rains or sewer line issues.

basement-drain-backing-up

Signs of a Basement Floor Drain Backup

There are several warning signs to watch out for that can indicate a backup. If you notice anything unusual about your basement floor drain, it’s important to get it checked out right away. Let’s examine a few:

  • Water Coming Up Through the Basement Floor Drain: Discovering an unexpected water feature in your basement is the most obvious sign of a backup. This might occur after heavy rainfall or use of appliances like washing machines, and can indicate a serious problem.
  • Bad Smells Coming From Drains: When wastewater backs up into your pipes, it can produce a foul odor resembling sewage. I experienced such a thing upon return from my trip, and let me tell you, it was awful! 
  • Gurgling Noises From Drains: If you hear a strange gurgling sound when flushing the toilet or draining a sink, rather than being a monster loitering in your pipes, it’s a clear warning sign. This sound indicates that there is trapped air in the plumbing due to a clog down the line.
  • Slow Draining Water in Sinks/Tubs: Take extra notice of how quickly water is draining from sinks, tubs, or toilets in your basement or around your home. This might be caused by a blockage in the main sewer line and can be an early warning sign of a developing blockage.
  • Water Backing Up When Using Appliances or Flushing Toilets: Another sign of a blockage further down the line is noticing a backup when using appliances or flushing toilets. If you start a wash cycle and then duck down into the basement to discover a mysterious puddle, it could indicate a serious problem.

Fixes for Basement Floor Drain Backups

Your basement floor drain backing up is not the end of the world, and you won’t have to throw out your entire basement. There are several ways it can be fixed, depending on the severity of the problem.

Immediate Actions:

It can be easy to panic upon noticing a backup in your basement. Thankfully, there are a few things you can do straight away to help prevent more damage.

  • Firstly, turn off water sources in your home. If you’re using the sink or a family member is in the shower, tell them to switch it off immediately to prevent further backup occuring.
  • Next, you can shut off the main water supply. Locate the main water shut-off valve in your home. It can either be on an interior wall in your basement, near the water meter, or outside if you have an older home. 
  • Rotate the handle to switch off water in your home. You might need a tool such as a wrench or pliers for this part. You can then test a tap to ensure you have shut off the water correctly.
  • Finally, remember to avoid chemical drain cleaners to clean the backup. While this might seem like an obvious choice to fix your problem, it can actually worsen the problem and pose several risks to your health and your home.

DIY Solutions for Minor Clogs:

You might like to try some DIY solutions before calling a plumber for your minor drain backups. If you have some tools around your home, it might be a cost-effective option.

  • One method is to use a sturdy plunger to unclog the floor drain. Ensure a tight seal to create ample suction to dislodge a minor clog. You will need to plunge vigorously several times for best results.
  • Another method is to insert a flexible drain snake into the drain. This handy tool can be twisted to break up or remove blockages that are deeper in the pipes.

Professional Solutions:

If you are unable to fix the problem yourself, it might be time to call in a plumber. There are various (and complicated ways) that they can fix a backed up basement drain.

Some might start out with a camera inspection. This involves using an HD sewer camera to inspect the drains and locate the blockage or defect. At this point, you’ll know whether the issue is with your pipes or the main sewer line.

They will then proceed with an appropriate tool to clear the blockage or solve the problem. For example, they might use an electric plumbing snake (sometimes with blades at the ends if there are tree roots) to clear the debris.

Another tool that is normally used is a high-pressure water jet, which is extremely useful for clearing out any clogs and stoppages. This is normally used when dealing with the waste from your home (grease stoppages, etc.)

If the problem extends beyond your home, the plumber might suggest a sewer line repair or replacement. This will be employed for the most serious issues, such as degrading pipes or issues with the main sewer line.

Preventive Measures

As with anything else in life, backed up basement floor drains can be prevented.

  • Carry out routine maintenance and cleaning: I recommend scheduling these annually to help prevent blockages and catch problems before they arise.
  • Install a backwater valve: This allows only sewage water to exit your home, and prevents water from backing up during rainfall, reducing the risk of overflow.
  • Install a sump pump: This device helps remove excess water from the lowest point in your basement, preventing future backups.
  • Consider replacing older pipes: Older pipes are more likely to be damaged or experience issues. Installing new ones with durable materials can help keep your plumbing in good shape.
  • Investigate your landscaping and guiding: An incorrect slope in the pipe that directs water away from your home might be causing drainage issues.
  • Conduct regular tree root maintenance: Tree roots can easily sneak into your pipes, so it’s important to keep them well-maintained to prevent this.
  • Be conscious of what you flush: You might not think much of it, but tipping hazardous waste materials such as grease, coffee grounds, wipes, feminine hygiene products, and hair down your drains or in your toilet can damage your pipes. Once built up, these materials can cause a serious blockage that might be costly. 

Conclusion

If you notice a build up of excess water in your basement, you must address this issue promptly. While some cases may have simple solutions, a water buildup in your basement could indicate a more serious problem with your pipes or the main sewer line.

Keep an eye out for warning signs such as water buildup, unpleasant odors, gurgling noises, and slow-draining sinks. Taking preventative measures early on is crucial to prevent the problem from escalating.

While you may be able to fix a minor backed up floor drain yourself, ignoring or improperly addressing the issue could lead to costly consequences and pose health risks in the long run.

If you notice any issues with your basement floor drain, you should seek professional advice and guidance from a plumber to address the problem and prevent future occurrences.

Marco
Marco
Meet Marco, a lifelong tinkerer and DIY enthusiast, developed a passion for plumbing after fixing a leaky faucet in his own home. Years later, he turned that passion into a thriving business, Amarco Plumbing, where he shares his knowledge and expertise with the community.