Can you build a pool next to a retaining wall

I’ve had homeowners in Calgary point at a steep cut in the yard and say, “Let’s put the swimming basin right here,” and I get why. It looks tidy on paper. Then we start talking about water, soil pressure, and where the excavation spoil goes, and the plan shifts a bit. A water feature that holds thousands of litres is heavy, and if the ground beside that grade-change structure is already under stress, the last thing you want is surprise movement a season later.

One of the first things I look at is depth and footing, because shallow bases are where problems begin. If you’re trying to tie a new excavation into an existing structure, you need to know what’s holding that structure up in the first place. This quick read on how deep should a retaining wall be lines up with what we see on site: the base and the buried courses matter more than the face people see from the patio.

Drainage is the next headache, and it’s usually the one people underestimate. I’ve seen jobs where the structure looked fine until a new water feature went in, then the wet soil behind it stayed wet longer, froze harder, and the lean showed up. If you’re already seeing cracks, bulging, or gaps, deal with that before you dig anything nearby. Here’s our walkthrough on how to fix a retaining wall, and yes, sometimes the answer is “take a section down and redo the backfill properly,” which nobody loves hearing.

Cost comes up fast, because people price the liner and the mechanical gear, then forget the earthwork and structure upgrades that make the whole setup safe. If you’re weighing materials or trying to keep the budget sane, this article on what is the cheapest retaining wall to build can help frame the options, but I’ll say this: the cheapest choice is only cheap if it doesn’t move.

Sometimes the conversation turns into a neighbour conversation, especially on sloped lots where one property sits above another. I’ve been on sites where the lower owner assumes the upper owner “must” handle it, and it gets messy. If that’s your situation, read is uphill neighbor responsible for retaining wall and get clarity early, before concrete shows up and temp fencing goes in.

If you’re in Calgary and the plan ends up needing new segmental block, matching existing colours and textures can be trickier than people expect. We get asked where to source decent product all the time, so this guide on where to buy retaining wall blocks in calgary ab is handy. At Sungreen Landscaping Inc we’ve been doing outdoor spaces since 1990, and we handle design through construction, plus the permits and engineer sign-off for taller structures. If you want us to look at your yard layout and grades, we do free consultations and 2D design samples, and you can reach us at (403) 256-7500.

Placing a swimming basin beside a grade-support structure

I get asked this a lot in Calgary: is it okay to set a swimming basin tight to a grade-support structure on a sloped yard. The short version is yes, it can work, but it is not a “close your eyes and dig” situation. Water, soil pressure, frost, and access for equipment all start arguing with each other pretty fast.

The big thing people miss is that an in-ground basin changes the way the soil behaves. Once you excavate, you remove weight on one side and add a heavy, water-filled shell on the other, and that can push a grade-support structure in ways it never saw before. I have seen a homeowner save space by tucking the basin right up against the blocks, then a spring melt hits, the backfill turns to mush, and suddenly there is a new tilt that was not there in October.

Before we even talk about shapes and finishes, I look at drainage and offset distance, plus what the existing structure is made of. Segmental block with proper gravel and perforated pipe behind it behaves a lot differently than old timber, or a dry-stacked “weekend project” that is basically dirt holding hands. If you are still shopping around for local help, this page on retaining walls near me gives a decent sense of what we handle and what questions to ask when you are comparing contractors.

If the grade-support structure is already showing a lean, cracking joints, or separation at the corners, stop and deal with that first. Trying to add a swimming basin beside a failing structure is like renovating a kitchen while the foundation is settling, it might look fine for a bit, then it gets expensive. We have a quick explainer on can you fix a leaning retaining wall, and honestly, catching it early is the difference between a repair and a teardown.

For taller grade-support structures, especially anything over 4 feet, we pull the City of Calgary permits and get an engineer involved. Some yards need geogrid tie-backs, some need better footing depth, and some need the basin moved a couple feet so the forces are not fighting. That part is boring to homeowners, I know, but it is also the part that keeps everything in the same place after a few freeze-thaw cycles.

• Plan for a drainage layer and an outlet that actually has somewhere to go, not just a pipe to nowhere.
• Leave access space for future service, filters, heaters, and any repairs to the grade-support structure.
• Expect more excavation and more export if the yard is tight, machines still need room to work.

Some people ask if they can just reinforce the grade-support structure themselves and call it good. I am not going to pretend small projects are impossible for a handy homeowner, but the details matter, base prep, compaction, granular, drainage stone, pipe, and proper cap. If you are curious about the anatomy of a good segmental system, have a look at how to build a block retaining wall, then compare that to what is actually in your yard. Most of the time, at least, the missing piece is what you cannot see behind the face.

At Sungreen Landscaping Inc we have been putting together outdoor living spaces since 1990, and we do the full scope from design to construction at 232043 Range Rd 283, Rocky View County, so we are not guessing how the pieces interact. If you want us to take a look, we do free consultations with 2D design samples, and every completed project comes with a signed warranty and a warranty rep. Call (403) 256-7500 and we will tell you straight if the basin belongs there or if it is smarter to shift it and sleep better when the spring runoff shows up.

Questions and answers:

How close can I build a pool to an existing retaining wall?

There isn’t one universal distance that fits every site. The safe spacing depends on wall height, footing depth, drainage behind the wall, soil type, and how the pool will be built (gunite/shotcrete, fiberglass, vinyl). Excavating for a pool can remove soil that helps the wall resist pressure, and the added water load near the wall can change how that soil behaves. A common approach is to keep the pool excavation outside the wall’s “influence zone,” then verify with a site-specific review. If the pool must sit close, the wall may need changes such as deeper footings, tiebacks, a reinforced stem, or a new engineered wall designed to work with the pool excavation.

Will digging for the pool make my retaining wall crack or lean?

It can. A retaining wall relies on soil in front of it for support, and the excavation can remove that support. Problems are more likely if the wall already shows warning signs: bulging, stepped cracks, separating cap stones, soil washing out from joints, or poor drainage (water staining, soggy areas, clogged weep holes). If excavation is planned near the wall, contractors often sequence the work to avoid sudden loss of support and may use temporary shoring. If the wall is not engineered or is older/damaged, it’s safer to assess and strengthen or rebuild the wall before pool work begins.

What drainage details matter most when a pool sits near a retaining wall?

Drainage is usually the make-or-break issue. You want water to move away from both the pool shell and the wall. Typical elements include: free-draining gravel backfill behind the wall, a perforated drain pipe daylighting to a safe outlet, properly spaced weep holes (if used), and a geotextile filter to reduce clogging by fines. Also plan surface grading so rainwater doesn’t run toward the wall or collect between the pool deck and the wall. If water gets trapped behind the wall, pressure rises fast, and the risk of movement goes up—especially after heavy storms or snowmelt.

Can I use the retaining wall as part of the pool structure?

Usually, no. Most retaining walls weren’t designed to act as a pool wall, and the loads are different. A pool wall must handle continuous water pressure and be waterproof; a retaining wall is built to resist soil pressure and drain water. If you connect them without engineering, cracking and leaks are common outcomes. If your design calls for a raised pool edge near the wall, the typical solution is a separate pool shell with its own reinforcement and waterproofing, plus a planned joint or gap that allows slight movement. In some projects, a new wall is engineered from the beginning as a combined system, but that’s a custom design, not a standard detail.

What warning signs tell me I should stop and get the wall checked before building the pool?

If you see any of these, pause the project and have the wall evaluated: the wall is leaning or bowing; long horizontal cracks or stair-step cracking; sections that look like they’ve shifted forward; gaps opening at the top cap; sinkholes or soft spots behind the wall; water seeping through joints or persistent wet staining; missing/blocked drainage outlets; or trees with large roots pushing near the wall line. Also be cautious if the wall is tall, built from stacked block without reinforcement, or has no visible drainage features. Catching these issues early is cheaper than repairing a failed wall after excavation and pool installation.