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Basement Flooding
Basement flooding can cause serious damage, personal and financial hardships. Call 905-546-2489 to if you cannot live in your home due to flooding. Staff will direct you to Hamilton Housing for emergency shelter support. In extreme flooding situations within the City of Hamilton, City Council could enact two compassionate grant programs if widespread flooding occurred due to heavy rain events. We will post more information if there is widespread flooding.
Types of basement flooding
There are a few different types of basement flooding:
- Infiltration flooding – when soil around your home becomes saturated or when the ground water level rises higher than your basement, water will get into your basement through cracks in the foundation walls and floor.
- Overland flooding – when water flows overland it may enter basements through windows, doors, vents and other openings. This could be due to improper grading, exposed window wells, an extreme wet weather condition that exceeds the capacity of overland routes or underground pipes.
- Sewer backup flooding – extreme weather events can overwhelm the City’s sewer system and result in flooding. When this happens the water level in the system rises above the normal design levels. This condition is referred to as surcharge. Basement flooding can cause serious damage and create a health hazard if not addressed properly.
Potential causes of flooding
A. Weeping tiles and downspouts connected to the sanitary sewer
During heavy rainfall, the water from the roof eavestroughs that are connected to the weeping tile through the downspouts may cause weeping tiles to become overwhelmed. If your weeping tiles are connected to the sanitary pipes, this may cause rainwater or sewage to back up in your home.
Solution: Disconnect weeping tiles and downspouts from the sanitary sewer system.
Have a qualified plumber investigate disconnecting your weeping tiles and downspouts from the sanitary sewer system.
B. Malfunctioning sump pump
If your home has a sump pump, it may have malfunctioned. This could cause your basement to flood.
Solution: Replace your sump pump
Make sure you maintain your sump pump properly. If your sump pump stopped working in the past, contact a qualified plumber to replace it. It is common for homes to lose power during severe storms, which can affect sump pump operation. Install a battery backup on your sump pump to avoid this.
C. Surface water
Basement flooding can occur:
- when the ground is saturated around the foundation walls
- when weeping tiles are not working properly
Solution: Smart landscaping
- Check that the ground around your house slopes away from your foundation. This helps keep water from entering through cracks in your foundation or overloading the weeping tiles. View more information about lot grading and drainage.
- Direct your downspouts away from the home where water can be easily absorbed, such as your lawn or garden.
- Connect the downspout to a rain barrel and direct the overflow hose towards your lawn or garden, not onto your neighbour’s property.
D. City sanitary sewer pipe full
Sewage can back up into the basement if the City’s sanitary sewer pipe is full due to large amounts of water.
Solution: Flood proofing devices
Homes prone to flooding may benefit from plumbing improvements. These include:
- Backwater valve
- Sewer lateral repairs
- Installations of sump pits and pumps
- Downspout disconnection
Consult a professional before doing any work. Check to see if you are eligible for the City’s Protective Plumbing program.
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