PORTLAND — Sixty-five miles of aging cast-iron pipes and 10 miles of bare-steel natural gas pipes in Portland and Westbrook should be replaced gradually, not at the accelerated pace the staff of the Maine Public Utilities Commission has recommended, city and state officials said Wednesday night during a public hearing at City Hall.

The commissioners were urged to consider the economy and the financial effect that an accelerated replacement project would have on ratepayers in 26 communities, including Lewiston-Auburn, that are served by Unitil, formerly Northern Utilities.

“This is not the time to choose the more expensive option,” said Carol A. Kontos, the new state president of Maine’s AARP Chapter.

PUC staff has recommended that natural-gas pipe systems in the two cities be replaced within 12 years, at an estimated cost of $64 million.

But the state’s public advocate and Unitil have recommended approaches that could take 20 to 30 years. The more conservative approach would ease the burden on consumers, they say.

“It seems apparent that this looming rate increase is being made based on an entirely optional and discretionary proposal and that it is not based on any sound evidence that there is a safety issue,” said state Rep. Peggy Rotundo, D-Lewiston, one of four state legislators who testified against the accelerated option.

“I have seen information that suggests that just comparing the company’s accelerated plan to your staff’s accelerated plan, a typical business would have to pay 123 percent more, or over $4,000 more, just to do the job a little faster,” she said. “This makes no sense to me and I urge you not to accept the proposal of your staff.”

Chairwoman Sharon Reishus said the board would consider public input before deliberating the issue at the end of June. The PUC will then issue an order directing Unitil to follow the staff recommendation or to take an “opportunistic” approach to replacing the gas pipes.

Unitil has proposed a third option: replacing pipes over 15 to 20 years and moving more than 10,000 gas meters from inside to outside houses and buildings.

Reishus said 96 percent of the cast-iron pipes still in use are more than 70 years old. Removing cast iron and bare-steel pipe has been a focus of regulatory efforts to improve public safety since the late 1990s.

Under the more gradual approach supported by Public Advocate Richard Davies, Unitil would replace cast-iron pipes with polyethylene plastic piping whenever a community excavates a street to do utility repairs. Davies said that would cost $40 million to $52 million.

“There is no safety benefit of investing $64 million at an accelerated pace,” Davies said before the hearing.

Mike Bobinsky, Portland’s director of public services, spoke against the accelerated option, saying it would force the city to dig up streets that are not scheduled for utility repairs.

“We are a pretty big city and we have a lot of stuff going on,” said Portland City Councilor Dory Richards Waxman. “This kind of project would impact our citizens in a big way.”

— The Sun Journal contributed to this story.