Two problem water supplies which have permanent "boil water" notices may be brought forward for upgrading by the Waitaki District Council.
The Otematata and Hampden-Moeraki water supplies may be upgraded next financial year.
The council proposes to spend more than $5 million on those and the Palmerston-Dunback-Goodwood and Enfield-Weston supplies, as part of a $10.3 million, seven year upgrade plan.
The council had originally scheduled upgrading the Hampden-Moeraki scheme in the 2011-12 financial year and Otematata in 2012-13.
However, changes to Ministry of Health deadlines for upgrading community water supplies to meet new drinking water standards has resulted in the council's assets committee recommending two be brought forward and six be delayed.
The six which could be delayed are Duntroon and Stoneburn (by one year to 2013 and 2014 respectively), Tokarahi, Awamoko, Kauri Hill and Windsor (by two years to 2014-15 and 2015-16).
The upgrading of all schemes is being done with borrowed money, but consumers will have to meet the cost of upgrading their own schemes by servicing and repaying individual loans.
This prompted Cr Struan Munro at the committee's meeting on Tuesday to question the effect on ratepayers.
He had been approached by some ratepayers in Otematata who were worried about it, he said.
One, who already paid $1700 a year in rates, said if there was a big effect they would have to leave the town, he said.
However, water-wastewater assets manager Martin Pacey said the council had to move the Otematata and Hampden-Moeraki upgrades forward because both had permanent boil water notices and considerable problems, particularly during the holiday periods when the towns were full.
He did not believe the rates effect would "be significant" for the benefit from a clean water supply.
The council also wanted to take advantage of a possible $2 million to $4 million subsidy from the Government which could be available to help upgrade the schemes.
The Oamaru water supply has already been upgraded at a cost of $12 million to meet the new standards, and Lower Waitaki is on the list for this financial year at a cost of $40,800.
