Why Does My Basement Drain Back Up During Heavy Rain?

Why Does My Basement Drain Back Up During Heavy Rain?

Avoid Outdoor Faucet Leaks - Turn On Your Hose Bib

Why Does My Basement Drain Back Up During Heavy Rain?

What You Need to Know:

Heavy rain can cause big problems for homeowners in Toronto and the GTA.

One of the most frustrating issues is a basement floor drain backup. When water or sewage comes up from your basement floor drain, it can be stressful. It can damage your floors, furniture, and belongings.

At DrainWorks Plumbing, we help homeowners prevent and fix these problems.

From drain inspections, to installing backwater valves to providing waterproofing solutions, we've got you covered. This blog will explain why drain backups happen, how to prevent them, and the services we offer to protect your home.

My Basement Drain Backs Up During Heavy Rain... What's Going On?

When there's heavy rainfall, the city's sewer system often struggles to keep up. This can cause water to back up into homes. If downspouts remain connected, heavy rain may not drain away properly. Here's why it happens:

 *  City Sewer Overload: Storms can overwhelm the municipal sewer system. When this happens, water flows back into basements through floor drains.

*  Clogged or Blocked Pipes: Grease, debris, or even tree roots can block your pipes, making it harder for water to drain properly.

*  Old or Damaged Pipes: Cracked or aging pipes can leak or allow water to seep in.
These problems are common in older homes or dense areas. Also high water tables in certain parts of the city can cause groundwater flooding in basements.

How to Stop Basement Flooding
After A Heavy Rainfall

The good news is that you can take steps to protect your home. Here are the best solutions:

1. Install a Backwater Valve

 A backwater valve is a device installed on your main sewer line. It blocks water from backing up into your home when the city sewer is overloaded.


This can help protect your home during storms. Plus, the city of Toronto offers subsidies to cover up to $1,250 of the cost.

A diagram showing how a backwater valve works

2. Waterproof Your Home

an internal waterproofing service seals your basement walls and floors from the inside to stop water from seeping in.

External waterproofing adds a layer of protection to your home's foundation, keeping water out and directing it away.

3. Use Water Control Systems

Installing a weeping tile or a sump pump can manage excess groundwater, especially in areas with high water tables.

4. Disconnect Your Downspouts

Disconnecting your downspouts ensures rainwater doesn't flow directly into the city's sewer system. Instead, it redirects water safely away from your home and reduces the chance of flooding.

Check out the section below for more details.

5. Clean and Inspect Your Drains

Regular maintenance, like camera inspections and drain cleaning, helps find and clear clogs before they cause backups and damage.

6. Fix or Replace Old Pipes

Damaged pipes can let water into your basement. Replacing them with stronger, newer materials can keep your system working better for longer.

More On "Disconnecting Downspouts": A Simple Way to Prevent Basement Flooding

One easy and effective way to protect your home is by disconnecting your downspouts. This prevents rainwater from flowing directly into the city's sewer system.


This can reduce the chance of an overload that could back up into your home. Instead, water is redirected onto your lawn or a safe drainage area, allowing it to soak into the ground naturally.

Why Disconnecting Downspouts Matters

1. Reduces Sewer Overloads:
Less water entering the sewer system means a lower risk of backups during heavy rain.

2. Protects Your Foundation:
Redirecting water away from your home prevents pooling near your foundation, reducing the risk of leaks.

3. Environmentally Friendly:
Allows rainwater to naturally return to the ground instead of being treated as wastewater.

How To Disconnect Downspouts

First make sure to check local rules:

1. In Toronto:
Downspout disconnection is mandatory in many areas. Make sure your home is compliant.

2. Extend the Downspout:
Use a pipe or extension to direct water at least 6 - 10 feet away from your foundation.

3. Install a Rain Barrel:
Collect rainwater to reuse for watering your garden or lawn.

The City of Toronto's Basement Flooding Protection Subsidy Program

Toronto offers financial help for homeowners who want to prevent flooding. Through the Basement Flooding Protection Subsidy Program, you can get reimbursed for installing protective devices like backwater valves and sump pumps. Here's what's covered:

Backwater valve installation: Up to $1,250


Sump pump installation: Up to $1,750


Pipe severance and capping: Up to $400

How to Qualify:

In order to quality you need to satisfy the following:

1. Your home must be in Toronto


2. You need a licensed plumber for the work

3. You must be up to date on your taxes and utility bill payments

4. You will need a permit for the backwater valve

5. The address must not have previously accepted the subsidy.

These subsidies can save you money while helping protect your home.

You can apply for the program
here.

A sign that says prevent this on it

Our Services & How We Help!
At DrainWorks Plumbing, We Provide All The Services You Need To Fix And Prevent Basement Flooding:

At DrainWorks Plumbing, we provide all the services you need to fix and prevent basement flooding:

1. Plumbing Drain Camera Inspections:
We use cameras to look inside your pipes and find problems like blockages or cracks.

2. Drain Cleaning Services:
Clogged pipes? We'll clean them out so water flows smoothly.

3. Drain Repairs and Replacements:
Whether you have cracks, leaks, or old broken pipes, we can fix or replace them.

4. Waterproofing Services (Internal and External):
Keep water out of your basement with our professional waterproofing solutions.

5. Water Control Systems:
From weeping tile to sump pumps, we help manage excess water and protect your home.

6. Professional Backwater Valve Installation Service:
A must-have for preventing sewer backups during heavy rain.

Frequently Asked Questions (FAQ

1. Why does my basement flood during heavy rain?

Rain can overload the city's sewer system or seep into your basement through cracks in pipes or your foundation.

2. What is waterproofing?


Waterproofing stops water from entering your basement. Internal waterproofing works inside your home, while external waterproofing protects your foundation from the outside.

3. What is a backwater valve?


A backwater valve is a device that blocks sewer water from backing up into your home.

4. How much does waterproofing cost?


Costs vary depending on your home's size and condition. Contact us for a free quote.

5. Do I need a sump pump?


If you have a high water table or frequent flooding, a sump pump is a great way to manage excess water.

Four pictures of a house with the words external waterproofing at the top

Areas We Service

At DrainWorks Plumbing, we're proud to serve homeowners across Toronto and the GTA.
Each area we service has its own unique challenges, and we're here to help. We are:

Licensed Plumbers in Toronto
Toronto's old sewer systems can't always handle heavy rain. We specialize in backwater valve installation, waterproofing, and fixing drains to keep homes across the city safe and dry.

Licensed Plumbers in Etobicoke
Etobicoke's older homes and riverside properties often deal with backups and flooding. We provide expert solutions like drain cleaning, internal waterproofing.

Licensed Plumbers in Mississauga
Mississauga's rapid growth and new developments sometimes mean overloaded sewer systems. Whether you're in Port Credit or Streetsville, we offer services like waterproofing and drain repairs to keep your home protected.

Licensed Plumbers in Oakville
Oakville's high water table makes waterproofing and water control essential. From sump pumps to external waterproofing, we'll make sure your home is safe from flooding.

Licensed Plumbers in North York
With both old homes and new builds, North York faces a mix of plumbing challenges. We handle everything from drain cleaning to pipe replacement to keep your home dry and damage-free.

Licensed Plumbers in East York
Many East York homes have older pipes that are prone to clogs and leaks. We specialize in upgrading these systems and providing internal waterproofing to stop flooding before it starts.


Licensed Plumbers in Scarborough
Scarborough's mix of urban and suburban homes often struggles with sewer backups after storms. From backwater valves to external waterproofing, we'll help you prepare for heavy rain.

Contact DrainWorks Plumbing Today!

If you are constantly dealing with basement flooding? Want to prevent it from happening again? DrainWorks Plumbing is here to help.

We proudly serve Toronto, Etobicoke, Mississauga, Oakville, North York, East York, and Scarborough.

Call us at
416 486-0000 or book a plumber online today!

Let us help you protect your home and give you peace of mind-no matter what the weather brings.

Thanks For Reading

"Why Does My Basement Drain Back Up During Heavy Rain?"

Thanks for reading "Why Does My Basement Drain Back Up During Heavy Rain?".

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