Retaining Walls: Overcoming the Challenges

Retaining walls are a versatile landscaping addition because there is such a variety of types of walls and because they serve so many different functions at the same time. For instance, they could help form basement walls, manage runoff, and enhance aesthetic appeal all at once. But like anything else, retaining walls come with their own set of challenges, even though they provide so many benefits. This post is meant to serve as a guide to aid you in building and maintaining a retaining wall that suits all your needs without the maintenance struggle. Purpose, Benefits, and Design Considerations of Retaining Walls One of the best ways to build and maintain a retaining wall with limited problems is to understand its functions and benefits. Here’s an overview:

• Erosion Prevention: A retaining wall helps keep soil in place, which is especially helpful for yards with minimal shrubbery or trees that don’t have roots, keeping the soil in place.
• Structural Support: In a similar vein, retaining walls also act as structural support by keeping soil in place.
• Runoff Management: In addition to typical erosion prevention, retaining walls also slow the flow of water as it moves downhill, ensuring that soil, nutrients, and plant life stays in place.
• Sinkhole Prevention: Because retaining walls manage runoff so effectively, this translates to sinkhole prevention–sinkholes form when too much water pools beneath the surface and the surface is no longer supported. However, with runoff management, sinkholes are less likely to form.
• Tiered Landscape Creation: One of the most common jobs of a retaining wall, they also add height to your landscaping, creating privacy, seclusion, or simply an aesthetically appealing wall.
• Leveling Management: Similarly, they’re also commonly used to level out your yard Basement Wall Formation: Large-scale retaining walls also help form the walls of larger structures, such as basements, underground garages, and metro stations.
• Aesthetic Enhancement: They’re especially known for their curb appeal.

Design Considerations There are three main considerations to think about when designing your retaining walls: the soil conditions of the site, the site’s drainage system, and load and pressure calculations. The type of soil on the site and the drainage system will directly affect the maintenance needs and longevity of the retaining wall. Thinking about how these things will interact with the wall will help you decide which type of wall you need and which materials to use. When it comes to load and pressure calculations, a professional installer can help you determine what your soil can handle. But it’s important to remember that the weight of the soil, the weight of the wall, and the earth’s pressure are all important factors when determining what type of wall will fit your yard best. Common Retaining Wall Challenges & Solutions
Drainage Issues As mentioned above, retaining walls are under a lot of pressure–literally. Installing a proper drainage system is crucial to avoiding collapse, as collapse often comes due to water pooling behind your retaining wall. Here are some drainage solutions that will help take the load off:

• Liquid Membrane: You can use a liquid membrane to apply a rubberized coating over your retaining wall to prevent water penetration.
• French Drains: French drains are a common drainage solution for any situation that simply diverts surface or groundwater away from a specific area.
• Channel Drains: Channel drains work similarly to French drains, the difference being that channel drains are typically installed into concrete.
• Filter Fabric: Covering the drainage stone layer with filtration fabric helps protect it from clogging.
• Aeration: Aerating your lawn allows your grass and other landscaping to absorb more water, helping with drainage issues. But keep in mind, you may need to combine aeration with another drainage solution.
• Dry Creek Bed: These landscape features use rocks, plants, and spill rocks to imitate a creek to help channel excess surface water.

Wall Failure & Collapse Retaining walls, like any wall, can collapse for many reasons, but the two most common reasons for collapse are poor drainage and poor construction. Ultimately, there are two solutions for a collapsed wall: strengthening the wall, and stabilizing the wall. In order to strengthen the wall, you can try transferring some of the force to the base by extending the base’s footing, or applying concrete to the base. This is usually a good solution if the reason behind the collapse is poor construction. For wall stabilization, there’s always the option to use wall anchors to support the wall. This solution can work no matter the problem behind the collapse, but keep in mind that the soil behind the wall is likely the real culprit and should be assessed. More often than not, the collapse was a result of poor drainage, and you’ll need to test your soil and make a game plan for improving your lawn’s drainage to prevent future problems. Soil Erosion Similarly, there are also two main reasons for soil erosion at the base of your wall: poor drainage and simply not having enough soil. Here are some things you can do to help mitigate soil erosion at the base of your retaining wall:

• Backfill: Using high-quality backfill materials can help mitigate soil movement.
• Plant: Planting roots helps keep the soil in place so that water and wind won’t blow it away.
• Erosion Control Blankets: These are biodegradable mats that support soil stabilization and help prevent sediment runoff.
• Gutter Systems: Keeping your gutters clean helps prevent nesting places.
• Drainage: Seeing a trend here? Proper drainage helps keep water from pooling behind your retaining walls and spreading the soil particles.

Retaining Wall Maintenance & Longevity
Inspections & Repairs You want to get cracks and bulges inspected and repaired as soon as possible. Tackling the little problems will help prevent the need for rebuilds and larger repairs that will cost more money and require more care in the long run. But again, you should be able to avoid most problems by ensuring your yard has proper drainage before building the retaining wall. Managing Plant Growth, Cleaning, and Sealing When it comes to plant growth near your wall, it can be a tricky subject. You definitely want to have plant growth, as the roots help with any soil erosion problems, but you have to be mindful of the pressure plants will apply to your wall and how deep the roots will grow. A landscaping professional can help you decide on native plants that will help your wall instead of hurting it. A good rule of thumb is to put smaller groundcovers closest to or even on top of the wall, as their roots don’t grow deep enough to disturb the wall and they don’t provide a lot of pressure, and shrubbery and bigger plants at least three feet away from the wall. Sealing is not required for a retaining wall, but if you choose to do it, it must be cleaned first. You can do this with a pressure washer or with a bristled brush and some soapy water. Cleaning the wall is fairly easy. You just want to do your best not to supersaturate it with water. You can then seal it with a heavy spray application and backroll it. Conclusion In conclusion, retaining walls are a landscaping element that adds loads of value to your space. Whether you’re looking to enhance your curb appeal or you need a more practical function from your retaining wall, it’s a versatile solution for lots of landscaping difficulties. Just remember to do it right and consult a professional from the start so your retaining wall will help you and not hurt you.