Fourteen exemption applications made to new water regulator

Regulator Taumata Arowai oversees new drinking water quality rules and standards. Photo / File

New Zealand’s water regulator has received 14 exemption applications over new drinking water standards, including one in Wellington relating to chlorine.

The new rules came into effect in November last year and are overseen by an entity called Taumata Arowai.

The agency was created as part of the Government’s response to 2016′s Havelock North campylobacter outbreak, which resulted in at least four deaths and up to 8320 people falling ill.

Wellington Water, which manages water for six councils in the region, says its Waterloo Treatment Plant does not comply with new chlorine rules.

The rules require water suppliers to increase the C.t value, which is determined by the amount of chlorine added to drinking water and the time it is in contact with the water before reaching consumers.

The increase is considered international best practice and further reduces the risk of bacteria.

Wellington Water acting chief executive Tonia Haskell said the

plant was compliant under previous rules and is only uncompliant because the rules changed, so the water is still safe to drink.

Up to 800 Lower Hutt households in Epuni and and Fairfield are affected.

Regular monitoring showed there was no E.coli or any other potentially disease-causing organisms in the water, Haskell said.

An independent technical study has also reaffirmed to Wellington Water the current treatment process was effective, she said.

To comply with the new regulations, Wellington Water would have to either significantly increase the concentration of chlorine or increase the time the chlorine was in contact with the water before it reached customers, Haskell said.

“Increasing the chlorine concentration to this level, which is around two and a half times the current dose, could result in a significant change to the taste of the water or cause skin irritation. Alternatively, significant network upgrades and investment are needed to increase the contact time between chlorine and water.”

It’s not clear how much the upgrades would cost and Haskell said no other compliance problems had been identified in the network at this stage.

Wellington Water has applied to Taumata Arowai for an exemption until it can complete the upgrades needed to meet the new requirements.

Taumata Arowai said the application was being processed.

The regulator is considering 14 exemption applications, including two others relating to the same chlorine issuein Wellington.

Non-compliance with a single rule did not automatically mean that water may be unsafe, a spokesperson for the regulator said.

“While there is a slight increase in the level of risk to the safety of the drinking water supplied through the Waterloo Water Treatment Plant where the C.t value is not currently being met, we consider this risk is manageable by the supplier while the exemption application is being processed.”