Flood Prevention and Maintaining Your Homes Drainage System

February 3rd 2017
Flood Prevention and Maintaining Your Homes Drainage System


If there is a catch basin in front of your property that hasn't yet been cleared of snow and ice, please clear it off to help the water run off.
Also, to protect your property, make sure that your gutters, drains and any drains serving sunken patios or roof decks are clear. If you're concerned about snow on your roof, please do not clear it off yourself - hire a professional.

Flood Prevention and Maintenance:

Prevention and maintenance is the key to reducing the risk of water damage caused by flooding. Looking at your home now and fixing any problem areas before the next major rainstorm or rapid snow melt can save you a lot of money and inconvenience. To begin, an assessment of your home drainage system will make a difference in reducing your flood risk.

Homeowner's Guide to Flood Prevention:

  • - Clear eavestroughs, downspouts and catch basins of leaves and other debris that prevent proper drainage.
  • - Be sure grading around your home drains water away from all exterior walls.
    - Even clear eavestroughs can overflow in intense, prolonged rainstorms; so make sure water can run away from the home.
  • - Make sure disconnected downspouts are draining properly, ideally 1.8 metres(six feet) from basement walls.
  • - Ensure storm sewer grates (catch basin grates) both on and near your property aren't blocked by garbage, leaves, ice or other debris that would prevent proper drainage and potentially lead to flooding.
  • - Fix leaks in walls, floors, windows or foundations. Check for moisture along the walls and the floor and fill and seal any visible cracks.

Maintaining Your Home Drainage System:

Don't wait until there's water in your basement before taking action. It's good idea to evaluate the condition of your home drainage system - inside and out. If you find a problem, don't put off the repairs. Consider most flooding on private property is caused by a home drainage issue. Follow these simple steps to prevent the danger of flooding. If you are unsure of what to do, there are companies that specialize in Drainage Systems.

Eavestroughs & Downspouts:

- Clean leaves and debris from inside the trough and downspouts.
- Tighten elbows and other connections.
- Caulk and seal any leaks.
- Repair or replace sagging, badly dented or cracked sections.

Water pours off your eavestroughs into downspouts. If the downspouts are dumping the water right beside your foundation, it drains directly to the weeping tile and can easily overload your home's drainage. Extend downspouts so that water flows away from your house and does not collect next to the basement walls and windows. Also, be sure the water does not drain toward your neighbour's basement walls. It should drain away from your house toward the street, rear yard, or back lane. Clean debris from eavestroughs regularly.

Lot Grading:

- Check the slope from the basement wall.
- Check for settling, particularly under stairs and decks.
- Raise any low spots.
- Look for cracks or spaces on driveways, sidewalks and patios that are next to the foundation wall. Caulk or waterproof where needed.

If the land around your home slopes in toward the foundation, rainwater heads right for the weeping tile around the basement and can overload your foundation drainage system. The land around many homes settles over time, and then slopes in toward the foundation. If your lot slopes inward, you'll want to fill in and grade the lot so that, for at least 1.8 metres (6 feet) out from around the foundation, the land slopes away from your house. Build up the ground around your house so that water drains away from your basement walls. Also, examine sidewalks, patios, decks and driveways. These can settle over time and cause water to drain back towards your basement walls.

Proper drainage helps to:

  • - Reduce the amount of water flowing to your home's sewer system and to the main sewer system, and lessen the risk of sewer backup.
  • - Reduce water seepage into your home through basement windows and cracks in your basement walls.
  • - Keep the moisture content of the soil around and under your house stable to reduce the chances of cracking and shifting. If water collects next to your basement, it can make its way to the footings that support the basement walls. The increased moisture may cause the footings to heave or settle.
  • - Extend the life of your sump pump by reducing the amount of work it has to do.

Weeping Tile:

Weeping tile is a perforated plastic pipe that surrounds the foundation of a home. It sits in a bed of gravel. This allows excess groundwater to seep into it. This water is channelled to a sump pump, or the sanitary sewer system, or the storm water sewer system, depending on the age of the home. Some homes built in older neighbourhoods do not have weeping tile. This may not be a concern if other drainage elements like eavestroughs, lot grading, etc. are in good condition. Installing or repairing weeping tile is expensive but necessary in some cases. For example, weeping tile that is collapsed or clogged by debris should be repaired to prevent damage to the foundation and basement walls. You should seek professional advice from a plumber or qualified drainage contractor before making any decisions.

Sump Pumps:

A working pump plays an important part in flood prevention, channelling
groundwater away from the home. A good quality pump should last around 10 years, depending on how often it is working and the acidity and dirtiness of the water.
- Check and test your pump each spring before the rainy season begins, and before you leave your house for a long time. Pour water into the pit to trigger the pump to operate.
- Remove and thoroughly clean the pump at least once a year. Disconnect the pump from the power source before you handle or clean it.
- Check the pit every so often to ensure it is free of debris. Most pumps have a screen that covers the water intake. You must keep this screen clean.

Sump Pump Discharge Pipe:

- Check the outside pipe to confirm water is flowing to the street or back lane.

Sump Pit:

- Clean the pit each year after freeze-up. Weeping tile drainage may carry small amounts of soil, sand and debris into the pit from around your basement foundation.
- Some water may remain in the pit and cause a musty smell if it sits for a long time. If so, you can flush the pit by adding fresh water until the pump removes the stale water.

Backwater Valve:

A backwater valve is a device that prevents sewage in an overloaded main sewer line from backing up into your basement. The valve automatically closes if sewage backs up from the main sewer A properly installed backwater valve must be placed so that sewage backup will be stopped and not come out through other outlets in your basement, such as sinks, toilets, showers and laundry tubs.

- Make sure that you can get at the valve at all times.
- Check the valve regularly and remove any material that may prevent the valve from operating properly.

You will normally require a permit and inspection to install a backwater valve and sump pit. Since part of the basement floor will be dug up and since proper placement of these items is important, we recommend that you use a qualified plumbing contractor.

What can cause a flood in your home:

  • - Basement flooding can occur when there are problems with the sewer system. Knowing some of the causes is the first step toward prevention.
  • - Problems in the municipal sewer system. Sewers can collapse or become blocked by waste and debris. Sometimes the pumping stations located throughout the sewer main system can break down or malfunction. Construction activity on or near the water distribution system can also cause problems.
  • - Problems in the lateral from your home. If the pipe between your home and the sewer main becomes blocked with debris, wastewater from your home can back up into your basement. Such problems can be caused by a collapsed pipe, the accumulation of grease, paper, kitchen waste or other foreign objects. In some cases, tree roots are to blame.
  • - Spring run-off. Rapid snow melt can leak through cracks or joints in your basement walls or floor. You can avoid or minimize damage from spring run-off by making sure the ground yard slopes away from your foundation, allowing rain water to flow away from your home.
  • - Overloaded sewers. The sewer system may be unable to handle the additional water produced by heavy rains or the spring run-off. Water and sewage can back up into your basement through floor drains, or any other plumbing fixture located in the basement that is not protected by a back water valve.
  • - Help keep catch basins clear. Where possible, safely clear snow, ice, and debris from the catch basins in your area.

Responsibilities as a homeowner:

As a homeowner, it is your responsibility to maintain your storm drainage systems, any installed sump pumps, grading at the foundation and window wells, roof drainage downspouts, hoses and the storm lateral that leads from your home to the municipal storm sewer line. As well, you are responsible for maintaining your internal plumbing system, plumbing fixtures, piping and ventilation systems, floor drains, septic systems, and the sanitary lateral that connects your home to municipal sanitary sewer line.

For a certified plumber or drainage professional contact 604-542-2236 (outside Greater Vancouver contact 1-888-266-8806.)

Here is a video of Shell speaking with Bob from Drain Rock...