Colorado Springs is a city built on slopes, hillsides, and terrain that shifts with the seasons. Retaining walls are one of the most common landscaping and structural investments property owners make here — and one of the most commonly done wrong. A retaining wall that fails in Colorado usually does so for the same reason: it wasn’t built for Colorado.
Here’s what every Colorado Springs property owner should understand before starting a retaining wall project.
Why Colorado Springs Is Hard on Retaining Walls
Most retaining wall guides are written for generic conditions. El Paso County is not generic. Three factors make retaining walls in Colorado Springs fundamentally different from walls built in most other markets:
The 36-Inch Frost Line
El Paso County’s frost line — the depth at which the ground freezes in winter — is 36 inches. Every retaining wall footing in Colorado Springs needs to extend below that depth or the wall will experience frost heave: the upward movement caused by freezing moisture in the soil beneath the footing. A wall that heaves even a fraction of an inch in year one will progressively worsen with each freeze-thaw cycle. This is the single most common reason walls fail prematurely in this market.
Expansive Clay Soil and Hydrostatic Pressure
Colorado Springs area soils — particularly at lower elevations along the Front Range corridor — contain significant clay content. Clay soils absorb water and expand. Behind a retaining wall, this expansion creates hydrostatic pressure: a lateral force pushing against the back of the wall. Without proper drainage — specifically crushed gravel backfill, drain tile, and weep holes — clay soil turns every rainstorm and snowmelt into a slow assault on the wall’s structural integrity.
Caliche and Its Effect on Drainage
The caliche layer common throughout El Paso County affects drainage at depth. Where caliche is present, water moving down through the soil profile gets redirected laterally — often directly behind a retaining wall. Understanding where caliche sits on a given site is part of proper drainage planning for any wall in this area.
Retaining Wall Materials: What Works Best in Colorado Springs
Boulder Walls
Boulder walls are the most popular retaining wall type in the Colorado Springs area, and for good reason. Large natural boulders handle freeze-thaw stress exceptionally well — their mass absorbs lateral pressure and their irregular fit allows for natural drainage without requiring a perfectly engineered drainage system. Boulder walls also require minimal maintenance over their lifespan and blend naturally with Colorado’s landscape. For most residential applications in El Paso County, a properly built boulder wall is the most durable long-term investment.
Concrete Block (Segmental Retaining Walls)
Concrete block systems — segmental retaining walls — offer a clean, uniform appearance and reliable structural performance. They can be reinforced with geogrid fabric for taller or load-bearing applications, and they’re available in a range of colors and textures. Block walls perform well in Colorado’s freeze-thaw conditions when properly drained and backfilled. They require a higher degree of precision during installation than boulder walls, which makes the quality of the contractor more critical.
Timber Walls
Timber retaining walls offer a natural look and lower material cost, making them popular for lower-height applications — typically under four feet. The limitation is lifespan: even pressure-treated timber has a shorter service life than boulder or concrete in Colorado’s climate. For a garden border or small landscape feature, timber works fine. For anything load-bearing or over three feet tall, boulder or block is a better long-term investment.
Poured Concrete and Engineered Systems
For tall walls, walls supporting driveways or structures, or any application where engineered design is required, poured concrete or proprietary engineered systems provide the structural capacity needed. These projects typically require permits and stamped engineering drawings, and the construction process is more involved than block or boulder installation.
Do You Need a Permit for a Retaining Wall in Colorado Springs?
This is one of the most searched questions about retaining walls in the Colorado Springs area, and the answer depends on wall height and location.
- Walls over 4 feet tall (measured from the bottom of the footing to the top of the wall) generally require a building permit and engineered drawings from the City of Colorado Springs or El Paso County Building Department.
- Walls under 4 feet may not require a permit, but setback requirements from property lines, easements, and right-of-ways still apply — as do HOA rules if your property is in a governed community.
- Walls near property lines, drainage features, or easements may have additional requirements regardless of height.
- Walls supporting loads (driveways, patios, structures) are typically required to meet engineered design standards regardless of height.
Important: Permit requirements can change and may vary based on your specific location within El Paso County. Always confirm current requirements with the City of Colorado Springs Development Services (coloradosprings.gov) or El Paso County Building Department before starting construction. Permits are the responsibility of the property owner or general contractor.
The Drainage Rule: Why Most Colorado Springs Walls Fail
If there’s one thing to take away from this guide, it’s this: a retaining wall in Colorado Springs without proper drainage will fail. It may take two years or ten, but the freeze-thaw cycle, clay expansion, and hydrostatic pressure behind an undrained wall will eventually win.
Proper drainage for a Colorado Springs retaining wall includes:
- Crushed gravel backfill: At least 12 inches of crushed rock directly behind the wall face, replacing the native clay soil that would otherwise create pressure.
- Drain tile: A perforated pipe at the base of the wall that collects water moving through the gravel backfill and redirects it away from the wall’s footing.
- Weep holes: Openings through the wall face (for block and concrete walls) that allow water to escape if it builds up behind the wall.
- Surface grading: The ground surface behind the wall should slope away from the wall to direct surface water elsewhere before it can infiltrate.
How to Choose a Retaining Wall Contractor in Colorado Springs
The most important question to ask a retaining wall contractor in Colorado Springs is how they handle drainage. If the answer is vague — or if they don’t bring it up at all — that’s a significant red flag. Drainage is not optional in El Paso County; it’s what determines whether a wall lasts 5 years or 50.
Beyond drainage, look for:
- Direct experience building retaining walls in El Paso County specifically
- Knowledge of local soil conditions (caliche depth, clay behavior, frost line requirements)
- Clear communication about permit requirements for your project
- Itemized estimates that reflect the actual complexity of your site
KDM Earthworks builds retaining walls throughout Colorado Springs and El Paso County — boulder walls, concrete block, timber, and engineered systems. Every wall starts with a site assessment that accounts for soil conditions, drainage patterns, and load requirements before a material recommendation is made. Learn more about KDM Earthworks retaining wall services.