Sustainable Glenorchy says the Queenstown Lakes District Council has ''completely overreacted'' to a government report into a North Island water contamination event last year, and chlorinating the district's water supply this summer is ''overkill''.
On Tuesday, council chief executive Mike Theelen said all water supplies under the council's control, including Glenorchy, Arthurs Point, Luggate and Glendhu Bay, would be proactively disinfected to protect residents and visitors while the systems were under increased pressure and to ensure water remained safe to drink.
Last summer, the council chlorinated supplies for Arrowtown, Hawea and Glendhu Bay. Queenstown and Wanaka's supplies were already chlorinated.
It followed stage two of the Havelock North drinking water inquiry, which called for a major overhaul of water supplies and strongly recommended mandatory treatment.
During the Havelock North event about 5500 residents became ill with campylobacteriosis. Forty-five were admitted to hospital and it was possible the outbreak contributed to three deaths.
However, Sustainable Glenorchy spokeswoman Nikki Gladding said the council had not consulted the community, the item was not included in the agenda for today's council meeting, yet it had decided to chlorinate the system ''for no reason''.
''We strongly object to council chlorinating our water.
''They claim they are taking action to protect public health but there are other ways that they can do this.
''A good first step would be to protect the bores.''
Ms Gladding said other than protozoa, the community's water supply was compliant - and chlorination would not solve that issue.
She submitted filtration and UV treatment, as well as ''prevention strategies'' such as moving fences were alternative ways of treating water without adding chlorine.
Ms Gladding said the town's ''beautiful'' water supply should be maintained, rather than ''presuming the worst and treating it with a chemical''.
While she understood the council had to take all practicable and reasonable steps to comply with Drinking Water Standards, which included monitoring of drinking water and implementing a water safety plan, a comprehensive plan had been prepared for the town and was being implemented.
''The plan states that overall the water is of a good potable standard and has high acceptability from consumers and most would not want to see the supply chlorinated.
''In this plan council has taken notice of the community and now surely council needs to implement it.
''We believe this sudden deviation to chlorinate the water supplies in all the small communities in the Queenstown Lakes district is overkill due to the contamination of the Havelock North water supply and the subsequent outcome.
''Glenorchy is not Havelock North and deserves to be considered individually.
''It should be up to the community to decide whether our water should be chlorinated or not.''
Representatives for the Queenstown Lakes District Council were asked for a response and did not provide one by deadline.