While she understood these were an unexpected cost, Ms Plug said to pass this on as an additional charge for ratepayers was "completely unreasonable" - instead, the cost should have been planned as this work was part of council's core business.
The only way she, and other ratepayers with a fixed income could pay the "unexpected bill", was to find savings elsewhere in her family's budget.
"So we hold off on our dream plans, a holiday, any luxuries ... make small savings here and there which add up.
"I would expect this council to do exactly the same with these water-related costs."
She suggested the necessary savings could be found in council's "dream plans" outside their core business - which she labelled "champagne options" that were "of little direct or downstream benefit for our residents".
The council has attracted criticism for "white elephant" projects in the past, the most recent being a multi-use sports facility.
Nelson Park ward councillor Maxine Boag - whose constituency area includes Maraenui - expressed concern that those on low income would be "adversely affected" by the increase.
"When rates go up, rents go up, and we all know with the housing crisis ... a lot of people at the moment are choosing between paying their power bill and buying food.
"It really concerns me that we are putting an extra burden on those people."
Several councillors echoed this concern, and agreed with at-large councillor Kirsten Wise's suggestion that the appropriate time for a full review of council's services "and the potential luxuries that we offer" would be during the upcoming Long Term Plan (LTP) process.
Deputy Mayor Faye White said the LTP would be the time to figure out what the community wanted council to do with projects outside their core business.
"That is the time that we need to really drill in and say 'do we need to do this, is it a need or a want' and manage from there."
Although she doubted any councillors found the rate increase "palatable", she did point out the city's rates were comparably lower than other authorities - the average forecast rate would increase to $1985.
In response, council Chief Executive Wayne Jack said they did look for savings throughout their business, and where these could be obtained, they would generally go toward maintaining levels of service in current programmes.
The "big driver" in the additional rate increase was due to changing expectations following the 2016 Havelock North water contamination, and recommendations from the government inquiry into this.
"Yes water is a core business for council, but unfortunately the changing standards ... have resulted in some significant costs which could not have been forecast in the past years putting budgets together."