PIPELINES ARE ESSENTIAL FOR DISASTER RECOVERY
Infrastructure resilience is a critical factor in recovery from earthquakes and other natural disasters.
IN THE PIPELINE
The basics of living – clean water and sanitation – are among the first things people need to cope with a crisis. The pipelines that provide these services are a major lifeline factor, and understanding how and why they fail can provide the key to building – or rebuilding – better, more resilient infrastructure.
Following a major seismic event, long, deep cracks in the roads, leaning buildings and houses splintered like matchsticks demonstrate the above-ground damage earthquakes can cause. For underground infrastructure, it can be harder to tell.
Learning from New Zealand’s earthquakes
Following New Zealand’s major earthquakes in Christchurch in 2010 and 2011, Opus’ Technical Principal of Pipeline Materials, John Black, carried out extensive research and fieldwork to determine the extent of the infrastructural damage.
He focussed on the water supply, sanitation and storm water drainage infrastructure, and how different pipeline materials react to seismic events. The striking similarities between the ground conditions of Christchurch and those of the Vancouver area mean the effects on the buried pipelines of Christchurch might be relevant to the west coast of Canada.
His work drew on the similarities between the two countries, with major parallels including liquefiable soil and proximity to the Ring of Fire. John presented some of his findings to staff from the Metro Vancouver regional authority, as well as several local municipal authorities and other interested parties on the west coast of Canada.
Flexible and fixable pipelines
His conclusions and recommendations center on the key principles of ‘flexible and fixable’ pipelines. He advocates this approach on the understanding that large earthquakes find and break the weak links in any buried or above ground pipeline; and that when earthquakes happen, it is entirely possible that conditions will exceed design parameters.
In some cases, purposely designing weak links that can be easily accessed and repaired may be more straightforward and affordable than trying to create indestructible links. While the body of work around earthquake impacts is growing, it can be difficult to estimate the exact outcome and therefore, it is important to resist the temptation to over-engineer in response.
Over-engineered solutions can lead to unaffordable and sometimes unnecessarily complicated designs. In turn, these may simply transfer known issues to another location, or introduce new and unforeseen problems. While history is bound to repeat itself, by sharing what we know and applying lessons learned, we can ensure we are not bound to repeat mistakes, and help build safer, more resilient communities.