Why Real-World Testing Is Crucial For Stormwater Tank Reliability
You can spec the perfect underground detention tank system on paper, but it’s what happens under asphalt, tonnes of soil and decades of pressure that tells the real story.
It may come as a surprise to some, but in Australia, there’s no formal standard governing the structural performance of underground plastic geocellular systems used for stormwater detention tank installations. For anyone designing with these systems, it’s a serious blind spot.
No standards, no problem? Not quite.
In the absence of local standards, many in the industry have turned to the UK’s Structural Design of Modular Geocellular Drainage Tanks (SDMGDT) from CIRIA. It’s not law here, but it’s the best technical guide available as of this writing. It recommends rigorous lab-based testing to simulate various loads on geocellular structures.
Lab testing remains a crucial baseline as it allows for consistent product comparisons, controlled performance benchmarking and early design-stage modelling. There is no denying how it’s a necessary foundation. But it’s just that — a starting point. It can’t replicate the full suite of stressors that a stormwater detention tank will experience once buried and forgotten. Lab data gives confidence. Real-world testing gives certainty.
What labs can’t replicate
In a controlled environment, you get consistency. But variables stack up fast on site. A lab doesn’t simulate the truck rolling over a freshly sealed surface. It doesn’t account for fluctuating soil moisture, imperfect backfill compaction or long-term traffic vibration. Yet these are exactly the conditions that a detention tank must endure over decades of use.
Real sites also introduce irregularities that are challenging to model, unexpected settlement, hydrostatic uplift, subgrade failure or even installation shortcuts. All of these influence structural performance in ways that often go unnoticed until failure occurs.
That’s the gap real-world detention tank testing fills. It moves past theory and into performance under high-stakes conditions. After all, that’s what infrastructure reliability demands — proof, not assumptions.
ACO StormBrixx® put to the ultimate test
ACO went further to close the gap between lab assumptions and field realities. We conducted a full-scale live load trial on an installed 3-layer ACO StormBrixx® SD detention tank system. Far from a model or a simulation, this was a real-world structure, buried beneath compacted soil and asphalt, subjected to the same conditions you’d find in any urban installation.
Sensors measured both vertical deflection and lateral movement. The tank was loaded with the equivalent of 30 US tons, around 27.2 metric tonnes, emulating the weight of heavy commercial vehicles. In the end, our product didn’t just hold up. It delivered the kind of data engineers and specifiers rarely get to see: how detention tanks actually behave once they’re out of the lab and under pressure.
What this means for specifiers, designers and councils
More than proving a product’s strength, data from in-situ testing unlocks real insight. For one, engineers get visibility into how detention tanks interact with their environment. But the value goes beyond validation because now, design teams get the feedback loop they’ve long lacked. Installations can be recalibrated based on observation, not just assumed loads. This makes future designs sharper, leaner and more cost-effective without compromising safety.
For councils and contractors, it brings clarity to risk. The verifiable data allows asset managers to plan around actual performance thresholds instead of theoretical ones. That could translate to fewer RFIs, reduced liability and more informed maintenance planning over the life of the asset.
Trust the brand that helped set the benchmark
ACO was so early to geocellular drainage that we pioneered the real-world testing of it. While others rely solely on controlled lab tests, we’ve taken it further by combining CIRIA’s recommended testing with full-scale field validation under Australian conditions.
Want to see the test results? Get in touch with our team for technical specs, data reports or tailored project support.
