New Zealand

Cyclone costs New Plymouth $4.5m and exposes water vulnerabilities

18:43 pm on 19 December 2018

A report into New Plymouth's water crisis caused by Cyclone Gita reveals it had an economic impact of $4.5 million and highlights shortcomings in the resilience of the city's water infrastructure.

Water tankers have been deployed in New Plymouth after ex-Cyclone Gita damaged a crucial water pipe. Photo: SUPPLIED/ New Plymouth District Council

During the February storm a tree fell and broke a water main, causing 10,000 homes to lose water supply for three days.

Another 26,000 - over a quarter of the district's population - were issued a boil water notice for more than a week.

There were more than 1500 power outages and a civil defence emergency was declared.

Major industries such as the Tegal processing plant at Bell Block was forced to close down for two days costing the company hundreds of thousands of dollars.

The 50-page report prepared by the New Plymouth District Council's own staff - for cost effectiveness reasons - was peer reviewed by Wellington Water.

It made six major recommendations for improvement and 22 minor recommendations while concluding the council's response to the crisis "was rapid, effective and no notable failures were found".

It noted there were no reports of illness due to waterborne diseases and no sewage overflows.

The report's six major recommendations were

  • an adjustment of future operations and maintenance budgets
  • a study of appropriate infrastructure resiliency levels
  • a study into raw water sources for contingency use
  • risk assessment of water connections and installation of backflow protection devices at key connections
  • a review of all asset management data
  • an update of NPDC's emergency plans.
  • New Plymouth mayor Neil Holdom said ratepayers had effectively got what they had paid for.

    "There's an expectation from people and an actual fundamental belief that all of this stuff is bullet-proof when actually most of New Zealand's infrastructure is extremely skinny and fragile."

    "It will cost money to bring them up-to-date, but I think there is an expectation that that work needs to be done from the community."

    The report found numerous shortfalls in the water services infrastructure from pipe easements that were to narrow to offer the pipes any protection from falling trees to technical drawings being out of date.

    "It was apparent that some asset information is not documented and only exists in a few senior and/or ex-staff members' heads," the report said.

    The water and wastewater system were found to have little or no redundancy in case of an emergency, a variety of key valves were faulty and basic maintenance was not being done due to budget cuts.

    "Annual shutdowns for maintenance of key plant and equipment no longer took place. The disestablishment of the Mechanical Maintenance Supervisor role has contributed to this, the report said.

    Mr Holdom said the council was addressing the shortfall in investment.

    "As a result of our experience dealing with ex-Cyclone Gita, we asked the public during our 10-Year Plan consultation if we should invest more in our water infrastructure.

    "The answer was a resounding yes, so we've listened and are investing an extra $44 million in water network resilience over the next decade."

    Chief executive Craig Stevenson expressed his regret for for the water outage.

    "I want to again apologise to everyone for the inconvenience the disruption to our water supply caused.

    "We're releasing our 50-page incident report publicly which includes some useful findings that we're taking on board about our complex water network that features more than 800km of pipes ranging in age from near new, to more than 100 years old."

    Fast facts

    • Around 10,000 homes were without water for approximately three days and some 26,000 properties were issued a boil water notice for a further seven days.
    • There were no instances of water-related sickness during this period.
    • Once water supply was restored, during the three days of testing the number of water quality samples taken represented an approximate 400% increase on the routine sampling taken during normal operations.
    • The economic impact on the community has been estimated at $4.5 million.
    • A copy of the incident report can be found [http://www.newplymouthnz.com/en/Council/Council-Documents/Reports/Cyclone-Gita

      here]