Articles: Learn, Maintain & Repair

Avoid Basement Flooding by Using Natural Drainage

You can avoid basement Flooding by using the natural drainage around a home. Many basements flood when the rainy season begins. We explain how to keep the rain water away from your house and out of your basement

During the warm weather months, many homeowners will look down into their basements to find rising waters.

A basement can flood – or at least suffer from seepage – during a rainstorm as the ground around a home becomes saturated with rainwater. Water, as it flows underground, follows the path of least resistance, which can often be along the exterior of a basement wall. The pressure of rainwater forces it through any small cracks in the basement walls and floors, or at the joint where the basement walls meet the floor.

One way to prevent basement flooding and seepage is to waterproof the exterior basement walls of your home. That requires an excavation and a coating of the walls, a fairly expensive process. Another is to install a sump pump system, again another fairly expensive task for the typical homeowner.

A less expensive although fairly laborious method to waterproof your basement is through natural drainage techniques.

In a nutshell, you need to avoid basement flooding by keeping the water away from the home and using the natural drainage around the home. This involves routing rainwater away from your house, preventing it from seeping in through basement walls.

For example, many basement seepage problems are the result of poor grading of the ground away from the house. The ground around a home should slope away from the house. Sidewalks, patios, driveways that lean towards the house can also aggravate the problem.

To remedy the situation, the grade of the ground should be changed. This may require a pickup bed or two of dirt that can be spread over the ground. The grade should ideally slope about an inch or slightly more for every ten feet of ground. Sloping the ground will also require you to do a little landscaping.

It’s best to remove existing turf and then dump in the backfill. Then place the turf back over the new ground. Sloping sidewalks, patios and driveways, meanwhile, may have to be rebuilt or re-pitched to change the flow of water.

If you live on a fairly large lot, another way to divert water is to build a swale – a shallow trench that encircles three sides of the house in a sort of horseshoe pattern.

Remember, Insurance does not cover flooding. Also, if your yard is flooding, you have to figure out a way to stop the water from getting close to your home and into your basement.

Dig the swale at least six feet from the house. Make sure that the ground between the house and the swale pitches toward the swale. Then fill the swale with gravel or crushed stones and cover it with dirt and turf.

Another way to divert water from your home’s property is to construct drain tile pipes into the ground. These perforated ridged black plastic tubes gather water during rainstorms and thanks to a downward pitch, carry the water away from the house.
The first step in constructing a drainpipe is to map out an underground channel where it will go. Ideally, as with a swale, the ground from the house will pitch towards the channel containing the drain tile pipe.

Take note of any sidewalks or driveways the pipe may have to cross under. In addition, where it discharges – preferably near a city storm sewer or a retention pond – is also highly important.

Once you’ve mapped out a plan, dig out a trench about a foot deep to support the drain tile pipe. Next, lay in about an inch or two of gravel. Then place the pipe in the trench, with the perforations face down.

Cover the pipe with more gravel. Otherwise, the dirt can clog the holes. Finally, top the gravel off with a few inches of dirt and sod.

Avoid basement Flooding by using the natural drainage around a home
Avoid basement Flooding by using the natural drainage around a home

Another key to preventing basement seepage is making sure your home’s gutter system is in good shape and functioning properly. If the gutters are clogged, rainwater will pour over the sides, saturating the ground next to the foundation of the house. Clean gutters ensure the water is carried away from the house.

In addition, placement of the downspouts, the vertical pipes that carry the water from the gutters to the ground below, is critical. If the downspouts are just exhausting the water right next the foundation, that’s just aggravating the situation.

Downspouts should exhaust as far as away from the house as possible. This can be accomplished by extensions, such as a piece of downspout that runs along the ground on a downward slope, or downspout extensions that unroll when filled with water. The latter is especially good for downspouts that descend to a sidewalk.

A downspout can also be attached to an underground drain tile pipe to divert water away from the house.

© by Jim Sulski