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Harnessing digital systems following disasters

The New Zealand earthquake of 2011 provided an opportunity for digital infrastructure to prove its worth in times of crisis, says Thomas Joseph.

Thomas Joseph, Mott MacDonald

Disasters – everything from severe weather events to terrorism – can bring major shocks to infrastructure, while the interdependency of assets means cascade failures are felt far from the site of the original impact.

Digital infrastructure can play a vital role in the recovery effort that follows, helping to identify problems and solutions. This was our experience following the earthquake which devastated Christchurch, New Zealand in 2011.

"Although it took physical action to fix damage, digital infrastructure proved indispensable, and if rolled out to utilities and key assets it will ensure that recovery following major crises is as efficient as possible."

Five years earlier we had set up H2Know-how, our cloud-based water management system, on the city’s wastewater network. Thirty pressure, flow and ultrasonic sensors were installed across the sewer system and connected to the management platform via the internet, allowing city authorities to monitor flow rates and the time, duration and location of overflow incidents, to better manage the wastewater system.

The earthquake caused massive devastation above ground, with a quarter of all city centre buildings destroyed and up to 10,000 houses irreparably damaged. This was mirrored below ground with huge damage to subterranean assets, including the wastewater network which suffered numerous ruptures and reverse flows of sewage due to uplift of pipework.

While all these problems required traditional engineering solutions, having digital infrastructure in place provided a number of benefits:

Identifying breakages: Having been in place for five years, we were able to compare data being gathered across the damaged wastewater system with historical data. With an idea of what ‘business as usual’ looked like, we were able to spot which pipes had been damaged.

Measuring damage: Comparing historical data with water flow and pressure rates after the earthquake allowed us to ascertain the level of damage which had hit each pipe, differentiating between pipes which had been severed and those which had suffered less extensive damage.

Locating faults: Being beneath ground, there was little visible evidence of the many breakages the system had suffered. Our sensor-based system allowed us to locate problems which would usually only be indicated by their eventual effects above-ground.

Prioritising action: In the midst of a disaster recovery programme which is still ongoing today it was important to prioritise our response. With all breakages identified, we were able to decide which needed attention first, according to how much wastewater was being lost or the knock-on effects on other parts of the sewer system.

Although it took physical action to fix damage, digital infrastructure proved indispensable, and if rolled out to utilities and key assets it will ensure that recovery following major crises is as efficient as possible.

Applied to the gas or electricity networks, similar sensor-based systems will allow easy identification of faults in the system, especially where the infrastructure is below ground or buried within walls. Road networks will also benefit, with sensor-based systems helping authorities to manage the response to major accidents or road closures.

As well as enabling asset managers to better manage asset failures, digital systems could feed into municipal or regional crisis management strategies, with the cascade effects of major shocks quickly identified and remedied.

So when calculating whether or not digital systems represent a worthwhile investment, we should consider not just the many incremental efficiencies brought to functioning assets, but how digital infrastructure comes into its own when assets fail.

Thomas Joseph is Team Leader, Planning & Needs Analysis at Mott MacDonald (New Zealand) and the developer of H2Know-how.

If you would like to contact Jackie Whitelaw about this, or any other story, please email jackie.whitelaw@infrastructure-intelligence.com.