A petition opposing the chlorination of Rarotonga's water supply has been presented to the Clerk of the Cook Islands Parliament.
The clerk is expected to review it in the coming days.
Once the petition has been endorsed by the clerk, the Democratic Party MP Selina Napa has committed to presenting it during the current sitting of Parliament.
The petition was launched in September by the NGO Te Vai Ora Maori, which has been campaigning for the government to consider options other than chlorination.
Since then, 1510 people have signed it, nearly 10 percent of the population of Rarotonga.
The petition also opposes the imposition of water rates for domestic users.
However, Cook Islands Deputy Prime Minister Mark Brown has dismissed petitioners' concerns as the government pushes ahead with its plans to use chlorine.
"Every first world country uses chlorination to purify their water, including New Zealand and Australia and numerous Pacific countries.
"So, 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."