Christchurch City Council has lodged its first application with the national water regulator for an exemption from the requirement to add chlorine to Christchurch’s drinking water.
The Water Services Act 2021 makes it mandatory for owners of reticulated water supplies to add a residual disinfectant – chlorine – to the water, unless they obtain an exemption from Taumata Arowai.
The chlorine requirement comes into effect from 15 November 2022.
The Council has long signalled its intention to seek an exemption, but because Christchurch’s water supply network is made-up of different water zones, it needs to apply on a zone-by-zone basis.
“We have lodged our first application - for the Brooklands-Kainga distribution zone - and we will lodge applications for other zones as soon as we can,’’ says Council Head of Three Waters Helen Beaumont.
“A zone-by-zone approach offers us the quickest path to getting the chlorine removed from our water supply.’’
“While we work through the exemption process we’ll continue operating our water supply under our water safety plan. This includes having emergency chlorination ready to be turned on if monitoring shows a problem with the water supply,” Ms Beaumont says.
The Council needs to supply Taumata Arowai with an enormous amount of information to get an exemption. It must satisfy the water regulator that there are adequate safeguards to ensure it can deliver safe drinking water without the need for chlorine.
Ms Beaumont says Taumata Arowai has confirmed the Council can apply for exemptions based on a planned work programme, but it will not be able to stop chlorination until the work in that zone is completed.
“In some of our water zones we still have work to do in order to meet the guidelines for an exemption, particularly where we have older tanks and reservoirs. We will prioritize exemption applications for zones with the lowest risks while we continue work to upgrade the water supply network.’’
Taumata Arowai has advised that, depending on the size and complexity of each water supply zone, assessing an exemption application will probably take 50 to 65 working days.
“This is a new process so it is difficult to be exact about timeframes,’’ Ms Beaumont says.
“We will have a better understanding of how long the exemption process will take once our first application has been dealt with. However, we are working on the assumption that it will take several years to obtain exemptions for all water zones.’’