AMHERST — After the conclusion of business hours on Wednesday, the main branch of the Jones Library at 43 Amity St. is closed to patrons for the next 18 or so months, beginning the process for renovating and expanding the building for the first time since the early 1990s.

With the looming $46.1 million project expected to get underway in mid-to-late June, library officials will soon be shuttering the building as preparation for a move of services to 101 University Drive begins.

Town Manager Paul Bockelman recently executed a $35.77 million contract with Fontaine Brothers, Inc. of Springfield to handle the work on the project, designed by Finegold Alexander Architects of Boston. That work, expanding the building from 48,000 square feet to 63,000 square feet, will include removing the 1990s addition entirely and renovating the original 1928 building.

Before the library closes and work commences, the public is invited Saturday from 11 a.m. to 4 p.m. to meet with library representatives in the atrium for a farewell to the current building, including an overview of the project and a scavenger hunt.

At a recent Library Building Committee meeting, Bob Peirent, the special capital projects coordinator for the town, said 19,000 square feet of space is available at 101 University Drive, the majority on the second floor and part of the first floor of what is known as the Slobody Building.

“We have identified temporary space, it’s the temporary space we had identified previously,” Peirent said.

Peirent said the town went through three competitive procurements and 101 University Drive was the only space that was located in Amherst and had the best lease price. Identified as a unique property, the town is posting this for 30 days in the state’s Central Register, before negotiating the lease.

Library Director Sharon Sharry said all collections, with the exception of the adult collection, will be inside the temporary space.

“Most everything will fit at 101,” Sharry said.

Interlibrary loan and all programming will continue from that site.

“101 University Drive is quite lovely, I think, patrons are really going to love it,” Sharry said. It’s an accessible building with restrooms, has lots of natural light, free parking outside and is on a bus line.

Bockelman said the town fiber and Internet also run to the building, which is also where Amherst Media is located.

Because staff will be focused on packing and moving in the next several weeks, Sharry said during the initial closing of the main branch additional hours will not be immediately at North Amherst and Munson libraries.

The project is moving forward after the Town Council rejected an effort to rescind the borrowing authorization in April, and the state attorney general’s office determined there was no need for a hearing on bid protest from resident Joe M. Cook, Northampton’s former procurement officer.

Cook filed the complaint arguing that changes to the scope of the construction contract with Fontaine Brothers will be made due to additional work required, after town officials signed a memorandum of agreement with the Massachusetts Historical Commission. “This constitutes a clear violation of Massachusetts Public Construction Bidding law that limits change orders to changes that arise after the commencement of the contract,” Cook wrote.

The memorandum of agreement with the Massachusetts Historical Commission, including required preservation of historic woodwork, followed the federal 106 process the town had to follow to secure $2.1 million in grants, both a Challenge Infrastructure and Capacity Building grant from the National Endowment for the Humanities and an Economic Development Initiative grant from the U.S. Department of Housing and Urban Development.

“The town admitted that it intends to use change orders to implement the changes required by the MOA, which public bidding laws do not allow,” Cook wrote.

In response, Justin Polk, the assistant attorney general and hearing officer for the bid unit, rejected that.

“In sum, while the protestor may certainly have fair concerns that a violation will occur in the future, no such showing has yet been made, leaving this matter unripe for our review,” Polk wrote. “Therefore, the protest is denied without a hearing, but also without prejudice to the protestor renewing the protest if the current concern about a future violation comes to fruition.”

The capital campaign is continuing and has secured $40.02 million, which represents 87% of the total project costs, from all sources, said campaign manager Ginny Hamilton.

Hamilton said the campaign still has $7.12 million to secure, when including expenses.

Scott Merzbach can be reached at smerzbach@gazettenet.com.