Causes and Cures of Basement Sewer Flooding: A 4 Point Plan For Solutions

Sewer Service
August 15, 2023

by David Balkan


Your basement can flood for a number of reasons. In many if not most cases a flooded basement is not related to sewer flooding. The good news is that in most cases a flooded basement can be made to be a one-time event if proper action is taken. If the issue is sewer flooding, the urgency to address the issue is multiplied due to the inherent health issues that are both immediate and lingering.

Why Flooding In Your Basement May Be More Serious Than You Think

Flooding sewer water leak issues, unlike rainwater or groundwater, contain a multitude of health dangers such as bacteria. Cleaning up after flood sewer issues should be a key health concern. If the sewage infiltrates porous surfaces, such as sheetrock, a professional remediation company may be needed.

However, any basement flooding creates the potential for mold to grow and might require mold remediation. In many cases, your home insurance policy might cover some or all of the damage. Therefore it’s never a bad idea to contact your insurance agent.


The 5 Primary Causes of Sewer Flooding in a Basement

There are 5 very basic reasons why sewer flooding would occur in your basement:

  1. A main house sewer or building drain clog.
  2. The main house trap is clogged in the belly of the trap itself.
  3. Heavy rains or a large snow melt causes the public sewer to surcharge (backup).
  4. A structural defect in your drain system.
  5. The public sewer is inadequate for the required load or has a structural defect.

As per the NYC DEP the most common causes of a sewer backup is from blocked pipes due to the improper disposal of grease, wipes, and other items down toilets and sinks. To learn more from the NYC DEP read about sewer backups.

A 4 Point Plan to Cure Basement Sewer Flooding

Even a devoted DIY’er should strongly consider contacting a licensed local plumber to evaluate the technically complicated issue of diagnosing the true cause of sewer flooding. Doing the wrong job the first time can never be considered as saving money. With that being said, here’s the 4-point plan to consider eliminating your basement flooding issue:

1. Inspect And Check Your Main House Trap

Your main house trap is your first line of defense against sewer gases entering your home, and preventing objects from clogging your house sewer line. Team Balkan provides free site visits and is an expert at providing sewer trap inspections, repairs, and replacements. In many cases, a house repair is as simple as replacing the trap plugs or caps. To learn more read a complete sewer house trap tutorial.

2. Consider Installing A WiFi Sewer Alarm

State-of-the-art WiFi sewer alarms warn you of a potential sewer flooding issue way before it causes property damage or health concerns. A sewer alarm will warn you of a sewer issue before it backs up above the level of your floor, or overflows from a shower, bathtub, or toilet. This push alert is generated by a sensitive moisture and pressure component of the alarm. These alarms can be plugged into your electrical supply, and run by batteries that last around 6 months.


3. A Backwater Check Valve Can Prevent Sewer Flooding

Sewer backwater check valves are simple one-way valves that protect your home when a city sewer surcharges during heavy rain or sudden snow melt. If a city sewer fails, it will likewise prevent sewage from back flowing into your home. It’s important to note that backwater check valves do not hold back 100% of sewer backwater. With being said, sewer check valves are best suited for public sewer surcharges that only last less than 24 hours.

4. Sewer Flood Gate Valves Hold back 100% Of Sewer Water

Automatic knife-edged sewer floodgate valves are sophisticated devices that hold back 100% of sewer backwater for an extended period. Balkan is an expert on assessing if you are a good candidate for this device, and is an expert at sewer valve installations. Balkan’s experience and knowledge assures you that your sewer valve will be installed following the manufacturer’s instructions, and will function as designed to automatically prevent sewer flooding. A proper installation also assures you that the manufacturer’s warranty will be in full effect.


What are The 5 Other Causes of Basement Flooding?

As stated previously, most basement flooding is not caused by sewer issues. Here is a basic list of the 5 other causes of basement flooding. In most cases each should have a potential cure:

  • Porous foundation wall or floor allowing for water penetration.
  • A high water table (groundwater) that rises above the level of the basement floor
  • The outer grade of the property sloping towards the house, instead of sloping away from the house.
  • Roof leader lines let out to close to the outer wall of your house.
  • A burst or cracked hot water heater.
  • Failure of a sump pump.

Professional And DIY Cures For Basement Flooding

As with any home project, you’ll need to analyze your skill level and capabilities before you get in over your head to cure a flooded basement issue. With that being said, a basement or foundation waterproofing job is best left to a licensed and skilled professional. If you can’t afford to do the right job the first time, you certainly can’t afford to do the job two times.

Groundwater & High Water Tables

In the case of a high water table (groundwater), there are systems that professionals install that typically require a sump pump being connected to the house sewer. In most cases perforated pipe is laid under the floor, surrounded by crushed stone and filter fabric. This system prevents the groundwater from rising above the level of a floor, and the installation is best left to an experienced and licensed professional.

Re-Grading Outside Your Building or Home

If you require the regrading of your property to slope it away from your foundation, the very first thing to do is verify the required elevations needed to accomplish the task. You would then have to calculate the required material needed, or needed to be removed. That will go a long way in determining if this is a DIY project or not.

Re-grading your yard can direct water away from your foundation wall

Flooding From Roof Leader Lines

Perhaps the easiest of cures is to extend your roof leader lines further away from the outside of your foundation wall. In many cases the cure for roof rainwater penetrating your foundation wall is as easy as that.

Basement Flooding From A Failed Sump Pump or Burst Hot Water Heater

Lastly, the failure of a sump pump or a water heater is frequently the cause of basement flooding. Sump pumps should be manually tested every 6 months or so to make sure that they are not clogged with debris or non-functional. On the other hand, water heaters have clear life expediencies. It might be best to replace a water heater once it nears its expected failure date.

Team Balkan Is Your Sewer Flood Prevention Expert

The More You Know The Better We Look

Balkan is a family-run business that has been in continuous operation for over 70 years. Our quality of work, professional service, and total commitment to satisfying our customers mean that your sewer, water main, or drain line work will be done right the first time. An educated consumer is our best client.

Over 70 Years And Over 90,000 Customers

Team Balkan still provides the same courteous and friendly service that was a core principle of Joe Balkan’s since the early 1950’s. The Balkan family still oversees every aspect of the business, with a team of over 100 like-minded folks dedicated to your complete satisfaction. Over 90,000 satisfied customers would agree that Balkan Is The Team You Trust.  

No Subcontracting Guarantees Seamless Installations

Each and every aspect of your interaction with Balkan will be with a Balkan Team Member. Likewise, every aspect of your installation is performed in-house. As an example, restoring disturbed finished surfaces, such as concrete, is performed by Balkan in-house tradesmen. Excellence is not by accident.

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David Balkan

David Balkan is the CEO of Balkan Sewer And Water Main, the largest and most trusted service in New York City. David is extremely active in various NYC plumber organizations being the Chairman of the Subsurface Committee in the Master Plumbers Council, and Vice President of the Subsurface Plumbers Association. In addition David’s expertise is respected by officials of New York City agencies such as the NYC DEP, NYC DOB, and the NYC DOT. He frequently provides valuable input on a variety of industry related matters.

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