The petition, filed by the anti-chlorine groupTe Vai Ora Maori, also opposed water rates for domestic users.
The motion to accept the petition was defeated after the government MPs voted against it.
Justine Flanagan of Te Vai Ora Maori said their campaign was not over. They would seek the Speaker’s clarification on whether the petition can be considered regardless.
“Our island’s water is at stake and there are many solid reasons why we should not support chlorination of our water,” she said.
“Chemical treatment means chemical dependency and we will be relying on these chemicals coming into the country. We know from our experience with Covid-19 that we need to become more sustainable and we need locally relevant and applicable solutions.
“Chemical costs also involve chemical waste which the government has not addressed whatsoever.”
Flanagan said the 1433 signatories which represented the will of 20 per cent of voters.
The dismissal of the petition was reminiscent of the government derailing the 2014 Te Mato Vai petition, she said, which also questioned the integrity of the new water supply system.
Deputy Prime Minister Mark Brown last year dismissed petitioners’ concerns.
“Every first world country uses chlorination to purify their water, including New Zealand and Australia and numerous Pacific countries,” Brown said.
“I am finding it difficult that the extreme views held by certain people should be used to determine the best possible drinking water system for the people of the Cook Islands or the people of Rarotonga.”