Houston is one of Texas’ cities with the most unpredictable weather. Even though much of the year is dry and dusty, the Greater Houston area has a notorious reputation for heavy rainfall that can lead to significant flooding. Since flooding in Houston isn’t a matter of “if” but a matter of “when,” a major flood can happen anytime and anywhere, including in both coastal and inland locations.
But one thing that many Houstonians are unaware of is that flooding doesn’t necessarily occur due to prolonged rainfall but mostly due to the fact that water accumulates on and below the ground faster than the soil is able to drain it. Water content that remains high for more than 48 hours can saturate the clay soil under your foundation, causing it to swell and become soft. This swelling and softening will weaken the soil and make it unstable, which might lead to specific foundation problems, including shifting and cracking.
Because clay soil tends to absorb and hold water instead of letting it drain, designing a proper drainage system is your only chance to avoid foundation damage due to heavy rainfall. To design a proper drainage system, you need to consider the texture of the soil around your property, topography, and the drainage systems available nowadays.
To begin with, soil texture refers to the amount of clay, sand, and silt that a certain type of soil contains. Most clay-rich soils have between 20% and 40% clay and different amounts of sand and silt. Soil texture is important because it indicates soil behavior during wet and dry spells.
Topography refers to the landscape position, surface steepness, waviness, roughness, and any other elements that can influence the natural soil drainage and erosion.
Coming down to the drainage systems you could opt for, they’re divided into two main categories, as follows:
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Surface Drainage Systems
Surface drainage systems typically comprise multiple shallow ditches that will directly runoff away from your foundation. This category includes:
- Swale drains – Swale drains are broad ditches with gentle side slopes. These drains are used to control the flow of rainwater and direct it towards a final drainage point, such as a dry well or sewer line, or other areas of your property. Because swale drains keep water runoff from draining too quickly, they prevent storm drains from being overwhelmed by a sudden influx of rainwater. To further prevent flooding, puddling, and soil erosion, you can line your swale drains with vegetation, gravel, or stepping stones.
- Trench drains – Compared to swale drains, trench drains have a channel set in place with concrete and are usually covered with metal grates. Trench drains can have different widths and depths, which are determined based on the amount of rainwater they must divert from your property.
- Gutters and downspouts – The main purpose of gutters and downspouts is to collect rainwater and snowmelt from your roof and direct them away from your home. To prevent water from saturating the ground around your foundation and harming your home, downspouts should extend at least 3 feet away from the foundation on sloped land and 10 feet on flat land.
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Subsurface drainage Systems
Located beneath the surface, subsurface drainage is designed to remove any excess water that accumulates below the ground surface. This type of drainage is further divided into:
- French drains – A French drain consists of a perforated pipe, which is installed in a sloped trench dug around the foundation, just below the ground surface, and filled with gravel. The pipe collects the surface water as well as the groundwater, moving it to a lower point, where it usually goes into a swale drain, dry well, or another draining solution.
- Weeping tile systems – Although many people assume that weeping tile systems and French drains are the same, they’re actually different. What sets weeping tile systems apart from French drains is their placement and output. As opposed to French drains, weeping tile systems are installed deeper into the ground, where they collect excess groundwater, which is then directed towards a sump pit. Because this system is installed deeper than a French drain, it can protect your home from water damage as well as hydrostatic pressure.
If you don’t have a drainage system around your property or the system you have was improperly designed or installed, your foundation and home could sustain extensive water damage that might be time-consuming and expensive to fix. The easiest way to prevent this type of damage is to hire a professional who knows how to design a drainage system for a Houston residence. Once the professional selects the most appropriate type of drainage for your home, he will determine the drain size, spacing, and layout according to the unique characteristics of your property.
Since having the right drainage system is essential to protecting your foundation, home, and landscape from the harmful effects of water runoff and potential flooding, give us a call today to schedule an appointment with one of our experts!
