Many contractors in Calgary assume that a flat lot means no erosion risk, but that is not true. The city sits on glacial till and alluvial deposits from the Bow and Elbow rivers, which can erode quickly under heavy rain or spring melt. If you skip a proper soil erosion analysis before excavation or grading, you risk exposed foundations, sediment runoff into storm drains, and costly stop-work orders from the city. We have seen projects in the NW hillsides lose meters of topsoil in a single storm because nobody checked the soil erodibility factors first. That is why we run field tests and lab simulations to measure exactly how your soil behaves under water flow.
In Calgary, 2-degree slopes can channel enough runoff to remove topsoil in a single storm if the soil erodibility is not measured beforehand.
Methodology and scope
Calgary's glacial till has variable clay content, often between 20 and 40 percent, which affects both erosion resistance and compaction behavior. When we assess a site, we first classify the soil using a granulometry test to see the grain-size distribution, then run a permeability field test to measure infiltration rates. Our lab uses standard ASTM procedures to determine the soil's critical shear stress and erosion rate. We also evaluate the local drainage patterns and slope angle, because even a 2-degree gradient can channel runoff in this region. The result is a clear report that tells you where erosion will likely occur and how to prevent it.
Technical reference image — Calgary
Local considerations
We bring a portable flume channel to your Calgary site to simulate concentrated flow erosion. The equipment fits in a pickup and sets up in about an hour. We run water at controlled velocities over a soil sample and measure how much material detaches. This test replicates what happens during a heavy rain event on a bare slope. If your site has sandy layers or exposed till, the erosion rate can be surprisingly high. Without this data, erosion control designs are guesswork, and Calgary's stormwater bylaws require sediment control plans for any project over 0.5 hectares.
How long does a soil erosion analysis take in Calgary?
Field sampling and lab testing typically take 5 to 10 business days. If you need expedited results, we can prioritize your project for a surcharge.
What is the cost range for a soil erosion analysis?
The price range is CA$1.160 to CA$3.810 depending on the number of test points and whether you need a rainfall simulator or flume test.
Do I need an erosion analysis for a small residential lot in Calgary?
If your lot is on a slope or near a watercourse, yes. The city requires a sediment control plan for any project disturbing more than 0.5 hectares, but even smaller lots benefit from knowing your soil erodibility.
What standards do you follow for erosion testing?
We use ASTM D4647 for jet erosion tests and CSA + CSA + CSA + CSA + ASTM D422 (also CFEM Ch 2) (also CFEM Ch 2) (also CFEM Ch 2) (also CFEM Ch 2) (also CFEM Ch 2) for grain-size analysis. Our lab is ISO 17025 accredited for these methods.
Can you test frozen soil in Calgary's winter?
We can sample frozen ground using a core drill, but the flume and rainfall tests need thawed samples. We recommend scheduling analysis in spring or fall for accurate results.
