Do You Need Drainage Behind a Retaining Wall?
A retaining wall is essential in keeping soil and other engineering materials stable. It also adds to your home's aesthetics.
After the financial input in home construction and landscaping, you don't want to wake up to a tilted or bulging landscape or waterlogged soil in your yard.
Poor drainage is among the causes of retaining wall failure. Therefore, you should ensure there is proper drainage behind every retaining wall in your home.
Here are the reasons why you need drainage behind your retainer wall.
Understanding Retaining Wall Drainage
A retaining wall drainage is a system put in place to drain water that the soil behind the wall absorbs.
Your contractor can use different drainage systems to protect your retaining wall, such as
Weep holes at the base to funnel water out
Geofabric layer that prevents backfill from entering the wall and interfering with water flow.
Backfill aggregate made from gravel, stones or crushed rock. These materials form a thick layer between the wall and soil, hence preventing blockage of weep holes from soil sediments.
Drainage pipes. Also known as agricultural pipes, these perforated pipes direct water away from the wall.
Onsite drainage and soil compaction, which lowers the water-holding capacity of soil behind the retaining wall.
Importance of Retaining Wall Drainage
Retaining wall drainage prevents water accumulation behind the wall. The role of drainage behind a retaining wall includes:
1. Controls Water Flow
Water follows the path of least resistance. If your wall is in a sloppy landscape, water will flow towards its bottom.
Since the soil particles at the base are loose after construction, water flowing will erode it to the front of the wall. This leaves a partial void behind the wall, resulting in high pressure in the front and low pressure behind.
The pressure gradient can result in the tilting of the wall.
Constructing a drainage system behind the wall prevents erosion of soil particles and keeps the wall stable.
2. Protection Against Moisture Damage
Exposing retaining walls to a lot of moisture can cause them to crack, wear out and fail. And if you have dealt with a damaged wall, you know how costly it is to repair.
Besides, moisture damage on these walls interferes with your home's exterior aesthetics.
The following table summarizes how water can damage your retaining wall.
Effect of Water
How it Damages the Wall
Pressure buildup
Accumulation of water behind the wall leads to pressure buildup. This results in high pressure behind the wall.
High pressure behind the wall can damage its footing and cause the wall to collapse.
Erosion
Excess water behind the retaining wall can erode the soil at the foundation.
This makes the wall unstable and can result in tilting.
Rusting and rotting
Water accumulation behind the wall can cause damage to the wall by causing iron wires to rust while wooden parts rot.
These effects can:
Weaken the wall and shorten its lifespan
Lower its aesthetic value
3. Maintains Lawns, Gardens and Surrounding Streets
Poor drainage can cause water runoff over your retaining wall. This erodes the top fertile soil on your lawns, gardens and flowerbeds.
The grass on your lawn, flowers in your flower bed and along the streets, and your vegetable garden becomes unhealthy from poor nutrition.
During heavy rains, the runoff can uproot plants on either side of the wall and damage your yard's elegance. That is why you need a drainage system behind every retaining wall to divert rainwater to the right channels.
4. Increases Your Retaining Wall Longevity
Your retaining wall's lifespan depends on the drainage. As the soil surrounding it absorbs water, it expands.
The expanding soil exerts pressure on the wall, weakening it. With time, the wall can develop cracks, or tilt and fail due to a damaged foundation.
You can avoid this by ensuring the soil around your retaining wall is well drained.
Expert Drainage Services for Your Retaining Wall
Retaining walls keeps soil stable and minimizes erosion. However, poor drainage interferes with their effectiveness and can damage them.
Therefore, you need a drainage system behind the walls.
At Top Gun, we are experts in drainage solutions. We’ll provide effective drainage solutions for your retaining wall that will preserve it for years.
Contact us today and talk to one of our experts. We offer our clients quality services at reasonable rates.