For centuries, stormwater infrastructure has quietly supported the rise of our cities. Buried beneath our feet, it prevents flooding, preserves public health, and channels billions of litres of water away from roads, homes, and businesses. But now, the systems that helped build the modern world are falling apart — and most people don’t even know they exist.

The truth? Our cities are built on top of aging, failing stormwater pipes — and the cost of ignoring them is catching up fast.

A Legacy of Brick and Concrete

Early cities used what was available: brick-lined drains, hand-built with care, often still functional centuries later. As materials advanced, we turned to concrete, and in some regions, steel. These systems — thousands of kilometres long — were laid out with precision, relying on just the right amount of slope to move water efficiently from drain to outfall.

But here's the problem: concrete has a lifespan of about 100 years, and much of this infrastructure is now far older. Across Europe, the U.S., Australia, and Asia, cities are quietly dealing with the slow collapse of their underground arteries.

Ground Subsidence: The Hidden Saboteur

It’s not just age that’s causing these failures. As we draw down groundwater supplies to meet rising demands, the land above begins to sink — a phenomenon called land subsidence. And when the ground sinks, so do the pipes.

Stormwater systems rely on slight, continuous slopes to carry water. Even small shifts in the ground can disrupt this flow, causing debris to accumulate, pipes to break, and blockages to form. That’s when the real damage begins — including costly flooding, waterlogging, and internal corrosion from stagnant waste and acidic runoff.

Replacement Is a Nightmare We Can’t Afford

Unlike water or sewer pipes, stormwater systems run under both sides of the road. To replace them, you’d have to rip up streets, footpaths, and entire blocks — twice. Businesses shut down, residents lose access, and city budgets spiral out of control.

It’s one of the biggest reasons full-scale replacement isn’t even on the table. Instead, governments opt for pipe relining, patching the inside with protective layers. But this only extends life — it doesn’t address the cause: polluted runoff entering open drains unfiltered.

Shockingly, most municipalities don’t even consider stormwater infrastructure an asset, despite investing quadrillions globally since its invention 230 years ago.

The Pit Educting Industry: A Band-Aid with Side Effects

About 50 years ago, we created an entire industry around vacuuming waste out of drains — known as pit educting. In 2022 alone, this market was worth over $2 billion USD, and it’s growing rapidly as stormwater systems fail under mounting pressure.

But pit educting is flawed. It doesn't address the water quality problem. It doesn't stop mosquito breeding grounds. And it doesn't help us reuse the rainwater we're losing. Worse still, the vacuuming process mixes the debris into a toxic sludge, which usually ends up in landfills — even though much of it, like leaves and organic matter, could’ve been composted or recycled.

The Tipping Point Is Now

We are facing a global inflection point. If we continue down this path, our current stormwater systems will accelerate the degradation of rivers, wetlands, oceans, and groundwater aquifers — the very systems rainfall was meant to replenish.

But there is hope — and it begins with protecting the infrastructure we already have.

That means:

• Cleaning out stormwater systems before they clog or fail
• Installing filtration devices at the source to stop contaminants from entering drains
• Viewing stormwater not as waste, but as a valuable water source
• Tracking stormwater infrastructure as a critical government asset with scheduled maintenance, protection, and retrofit plans

The technology now exists. The awareness is rising. And the cost of inaction is becoming too steep to ignore.

The Bottom Line

Cities are built on top of aging pipes. Those pipes were never designed to carry the load — or the pollution — we put on them today. The system is cracking, both literally and metaphorically. But with innovation and urgency, we can preserve this hidden infrastructure, protect our waterways, and reclaim stormwater as the vital resource it truly is.

The world doesn’t need more pipes. It needs to protect the ones we already buried — before they take our cities down with them.

# stormwater infrastructure crisis, aging urban infrastructure, climate change and cities, failing drainage systems, water infrastructure collapse, stormwater contamination, toxic algae bloom.