LEWISTON – For 162 years, the Libbey Mill has perched on the edge of Great Falls, a testament to the city’s industrial heritage.

But a 1999 fire devastated the former cotton mill, and now its remnants will succumb to another sign of the times: the wrecking ball.

Barring the arrival of a last-minute guardian angel willing to invest between $15 million and $30 million into the crumbling mill, it likely will be demolished this summer.

“The reality is the cost associated with rehabilitating the building means it just isn’t feasible to do it,” said Gil Arsenault, the city’s director of planning and code enforcement. “It’s not even feasible to mothball it.”

Almost 100,000 square feet remains of the five-story brick behemoth that sits just above the Cowan Mill on a spit of ledge that juts into the Androscoggin River. Developer Travis Soule had hoped to rehab both mills into luxury condominiums, the cornerstone of a village complex redevelopment project called Island Point.

“We had a number of engineers and contracting companies out here, and they all said about the same thing, that the building was too far gone to be saved,” said Mike Carey, director of development at Island Point. “The general consensus was it would cost twice as much to rehab the building than could ever be realized in its sale.”

Arsenault said city estimates put the cost to mothball the old mill at about $150 per square foot. Rehab costs came in between $250 and $280 per square foot. The city has owned the building since late 1999 when it was seized for nonpayment of $300,000 in back taxes.

City and state historical commissions have been put on notice of the demolition plans, Arsenault said. Although the mill isn’t on the Register of Historical Places, it’s customary for the city to notify them in case they can raise the money to save historically significant structures.

The commissions have 90 days to respond. Arsenault said he doubts they will be able to save the mill, as they and former City Councilor James Carrignan did in 2000.

“The local commissioners toured the mill years ago,” he said. “It was in horrible shape then; it’s worse now.”

Since the tour, the floor of one of the upper stories collapsed, falling onto the floor below and weakening other parts of the building.

Carrignan, who now chairs the state Board of Education, said he was sad to learn of the demolition plans. Since retiring from his post at Bates College, he and his wife have moved to Harpswell and no longer remain active in Lewiston-Auburn organizations.

But he mourns the impending loss of the landmark.

“I think it’s very sad, that we lose a building that is part of the legacy of Lewiston and Auburn” he said. “It has great potential in terms of location and in terms of historic architecture for future use. It takes great patience and effort by developers to recruit investment and put money into it.”

The city has earmarked $300,000 in the fiscal year 2008 budget for the Libbey demolition. If the budget is approved, a bid for the demolition work will go out soon thereafter, said Norm Beauparlant, city purchasing director.

A separate bid to remove contaminants from the site is expected to be awarded on Monday, he said.

That work – including the removal of asbestos from the interior of the mill, oil-soaked wood decks and contaminants in the soil – is being paid through a $200,000 federal brownfields grant the city won about a year and a half ago.

Carey said the loss of the Libbey Mill changes the footprint of the $30 million Island Point project, a public-private partnership between the city and the developers.

“But the overall concept isn’t changed by it,” he said. The goal is still to combine condominiums with retail and restaurant space.

Last month Soule announced that he and his partners had secured the financing to move the project forward, as well as a letter of intent from a national hotel chain willing to build on the site.

“We’re happy where we are right now (with the negotiations),” said Carey.