Nothing can fully protect a home from water damage if
it's repeatedly exposed to outdoor flooding. Heavy spring rains often cause
deep pooling in the yard adjacent to the house. This water can eventually
penetrate most building materials (even concrete foundation) and damage the structure as well as the
home's interior. The best cure is prevention: Keep water and house as far apart
from each other as possible. Here are some ways to use landscaping to protect
your home from flooding during the rainy season.
Grade Wisely
If nearby ground is flat or actually slopes toward the house, water
intrusion will be a problem in heavy rain. The ground should slope away from
the house at a minimum of five degrees to divert water at least 10 feet from
the house. A five-degree slope means the ground surface six feet from the house
is three inches lower than the ground immediately next to the house.
Build Swales
A swale is a shallow, linear depression in the yard. During rain, it serves
as a channel to redirect water away from the house, allowing it to soak into
the ground along the way. A common yard swale is 6 inches to a foot deep and
two feet or more wide. It can be seeded with grass, clover or other plantings
to make it blend in. A swale to drain a residential yard is usually shallow
enough to run a lawn mower over.
Plant Grass
Large bare spots in the yard actually cause water to flow along the surface
of the ground faster and not be absorbed. The root structure of healthy growing
grass makes soil absorb water more rapidly. Plant grass to cover large bare
spots near the house. When mowing, don't cut the grass too short, which shrinks
its roots.
Install French Drains
Buried in a sloping, gravel-filled trench deeper than the home structure's
lowest point, a french drain consists of a perforated plastic pipe that
collects underground water. The pipe is routed in a direction to discharge that
water into a deeper, more absorbent area of the yard.
