New Zealand: Wellington adds water 'islands' as city lifeline after quakes
Much of Wellington's infrastructure is fragile and far from quake-proof
By Michael Taylor
Weeks after a powerful 2016 earthquake sent glass and masonry toppling from buildings in New Zealand's capital, work began on how the "lifelines of the city," such as water supplies, could be protected in the event of a similar or bigger disaster.
Less than two years on, a project to create 22 emergency water "islands" across Wellington has just been completed at a cost of NZ$12 million ($8 million), so that no one has to walk more than 1 km (0.6 miles) to get clean water after a quake.
Mike Mendonca, chief resilience officer at Wellington City Council, said the 2016 earthquake had reminded decision makers of "the power of mother nature", and hardened their resolve to invest in infrastructure.
Mendonca, whose role was initially funded by the 100 Resilient Cities network backed by The Rockefeller Foundation, pinpointed emergency water supplies as a key element of the city's resilience strategy developed last year.
"Our economy is not just about surviving, but thriving - and to thrive we need commercial and industrial quantities of electricity, telecommunications and water," Mendonca told the Thomson Reuters Foundation. "Water is life."
New Zealand experiences thousands of earthquakes each year, lying on the seismically active "Ring of Fire", a 40,000-km arc of volcanoes and sea trenches girdling much of the Pacific Ocean.
The 7.8-magnitude earthquake in 2016, which caused widespread destruction in the resort town of Kaikoura and badly shook Wellington, was estimated by the government to have cost the country's economy more than NZ$8 billion.
That disaster came as Christchurch was still recovering from a 6.3-magnitude quake in 2011 that killed nearly 200 people.
Wellington is judged to be at high risk because it was developed largely in the 1890s and early 1900s.
Much of its infrastructure is fragile and far from quake-proof, while many buildings are made of brick and masonry, without reinforced facades, risk experts said.
"Wellington is a great place to live, work and play but as we grow, the intensity of the way we live just magnifies and amplifies the consequences of a significant earthquake," said Mendonca.
Water resilience
After the 2016 quake, experts in Wellington - which uses about 140 million litres of water per day - estimated it would take up to 14 weeks to get water supplies back up and running as normal if a 7.5-magnitude earthquake struck the capital.
The city sits on major faultlines, meaning its network of water pipes often cross those lines, said Zac Jordan, deputy chief resilience officer at Wellington City Council.
Its eastern suburbs could be out of water for up to 100 days if a substantial earthquake hit, he added.
Funded by local and central governments, the new project taps into water sources across Wellington - whether open streams or drilled boreholes - to create 22 water stations or "islands".
Five local councils set up a company, Wellington Water Ltd, to undertake the work on the islands, and maintain them.
They consist of wooden huts containing a pump and water filter where Wellington's 500,000 residents can go to fill containers in a disaster.
For the first week after a large quake, people will be expected to rely on their own stockpiled water supplies. But after that, communities will start to operate the water islands independently of the main supply network.
"At a household level, we've continued to raise awareness of the need to store 20 litres per person per day for at least seven days," said Caroline Robertson of Wellington Water.
"This emergency water network ... will help our communities to become more resilient."
Understanding risk
Cities at risk of earthquakes should analyse where the vulnerabilities in their water network lie, and estimate the time needed to get supplies up and running again, experts said.
Utility companies and state agencies can then plan how to cut that time from days to hours, said Michael Bonte-Grapentin, disaster risk management specialist at the World Bank in Sydney.
Maintaining and strengthening water infrastructure, including dams and pipes, to make it more robust in an earthquake is also important, risk experts noted.
"We can be without power and use candlelight or not use certain appliances, but we really cannot stay long without water," Bonte-Grapentin said.
Trucking in emergency water supplies is costly, and can be logistically hard if roads and other infrastructure are damaged.
In Wellington, the next step is to train community members to work the water stations and distribute water in a crisis, said Mendonca.
"This earthquake two years ago was probably the one that really forced us to think hard about the resilience of our infrastructure," he added.