The Most Likely Spot a Landslide Will Break Your Pipeline? It’s Not Where You Think.
When people think about landslide risks to pipelines, they often imagine rugged mountains with steep slopes and pipelines running across treacherous terrain. And yes—that terrain is hazardous.
But the failure statistics from Western Canada tell a very different story.
It’s not pipelines in exposed mountainous terrain that fail most often—it’s the deeply buried pipelines installed by Horizontal Directional Drilling (HDD) through the slow-moving, gently inclined landslides flanking river valleys.
The good news? With the right data, tools, and expertise, these risks can be reliably identified and proactively managed.
A comprehensive study by BGC Engineering Inc. reviewed nearly 100,000 km of pipeline in Alberta and BC. Of over 7,900 slope crossings, about 14% were installed using HDD. Yet these HDD segments accounted for 35% of all landslide-related pipeline failures over a 10-year period.
Once adjusted for how frequently each installation type actually intersects landslides, the risk becomes even clearer: pipelines impacted by landslides are 15 times more likely to fail if they were installed by HDD compared to conventional trenching.
Pipelines impacted by landslides are 15 times more likely to fail if they were installed by HDD compared to conventional trenching
Why? It comes down to physics. At depth, soil and rock are stiffer, overburden pressures are higher, and pipe-soil interaction forces are significantly magnified. Unlike conventionally trenched pipelines that can sometimes be dug up and fixed, HDD segments are locked in place—often with no practical way to relieve stress or make a repair.
Why This Happens—and Why It Still Happens
Many HDDs were installed decades ago to cross rivers—not to avoid landslides. Without LiDAR or modern terrain analysis, historic installations often unknowingly crossed deep-seated landslide terrain. And in efforts to minimize cost and length, shallow HDDs were sometimes drilled directly through unstable slopes.
Many HDDs were installed decades ago to cross rivers—not to avoid landslides.
Even today, some new installations repeat this pattern. Unless geohazard specialists are embedded in design teams early, and HDD profiles are specifically evaluated against slope movement depth, the risk remains.
It's Dark Down There: Turn a Light on with IMU
Mile for mile, there is no higher value place to look for landslide impacts than on your HDDs. BGC has developed a screening framework that allows operators to quickly triage their HDD installations, identifying which ones are likely low-risk (“deep-effective”) and which need further investigation—or even mitigation.
Up to 50% of sites with critical landslide risk are first flagged through IMU bending strain signatures
Identifying whether a landslide intersects a pipeline typically requires expensive geotechnical instrumentation. But many pipelines already have inertial measurement unit (IMU) data available.
IMU turns the pipeline into an instrument—it measures subtle bend patterns that are early signs of landslide impact. These can’t often be seen from the surface, but they can be critical for catching a problem before it becomes a failure. Up to 50% of sites with critical landslide risk are first flagged through IMU bending strain signatures.
The Takeaway
If you’re assuming your pipeline is safe because it’s installed by HDD—think again.
- When HDDs avoid landslides, they reduce risk.
- When HDDs intersect landslides, they multiply it.
Let's Talk
Want to know if your HDDs are safe?
BGC Engineering Inc. and Cambio Earth are global leaders in pipeline geohazard assessment. We’ve evaluated thousands of HDD installations and have the tools and expertise to help you quickly identify and mitigate critical threats.
Joel Van Hove
Senior Geotechnical Engineer, Pipelines Team Lead