The Edgartown library has been provisionally awarded $4.59 million as part of an omnibus bond bill that authorizes a total of $137.5 million for public library construction across the state.

The grant would help pay for an expansion project for the library on North Water street with a price tag of $15 million.

The library began action on the project in 2004 when the town agreed to buy the Capt. Warren house next door to the library on North Water street.

The plan calls for the old Carnegie library building to be moved closer to the sidewalk on North Water street and for the Warren house to be torn down to make way for an expanded campus which will include an auditorium and more storage space.

A capital campaign committee set up by the Edgartown library foundation will handle the fund drive. Capital campaign chairman Robert Hughes aims to complete the drive before Dec. 31 2009, the first milestone date set by the state.

Mr. Hughes breaks down the costs as follows: $8.1 million for construction, $3.5 million for the purchase of Warren house, $1.3 million for architectural and design costs and $900,000 for fixtures and furniture. The capital campaign is also looking for an additional $1 million as an endowment.

According to Mr. Hughes, private donations and grants currently total a little over $1 million. Counting the money earmarked by the state and that paid by the town for the Warren house, Mr. Hughes puts the current total of funds raised at just under $10 million.

“We’re five sevenths of the way there,” he said.

The larger building and staff increases will mean an increase in operating costs paid by the town, although the exact amount is not known.

“There will be a modest increase,” Mr. Hughes said. He said $1 million sought by the museum as an endowment may help offset the increase. Speaking on Wednesday library director Felicia Cheney said the endowment may also be needed as a contingency fund for construction.

“We could start digging and uncover a huge rock on the site,” she said, adding: “something will come up.”

Mr. Hughes agreed that the budget is an estimate.

“Fourteen is a baseline, 16 would be a home run,” he said. “A little additionality in this day and age wouldn’t hurt.”

The cost of the project listed in the grant application filed with the state library commissioners is $15.2 million.

A spokesman for the Massachusetts Commissioners of Libraries said the numbers are estimates; the final tally may be different when the project goes out to bid.

Mr. Hughes said the library is a community center in Edgartown.

“The critical piece is 90,000 visitors a year are served by the existing library and it defines the character of the community,” he said. “There will be an 80-seat small auditorium space; it’s a critical facility, particularly off-season, for teen facilities and book clubs. Particularly in the desolation of winter, it’s the cornerstone of the village.”

Quoting Walter Cronkite, a seasonal resident of the Island and honorary chairman of the capital campaign, Mr. Hughes said:

“There’s no better escape from ignorance in our free society than the open door of a public library.”

Ms. Cheney said the capital campaign is in a quiet phase and will begin in earnest this fall.

“The timetable is scooted up us now,” she said, referring to the 17-month milestone date for the state grant.

Mr. Hughes said that with the $3.5 million purchase of the Warren house in 2004, Edgartown provided a required 25 per cent investment in the project.

Town administrator Pamela Dolby said a meeting is planned for sometime in the fall between the financial advisory committee, selectmen and library representatives but she was unclear as to whether the project would go before voters again.

“I don’t know at this stage,” she said

The state grant comes with strings attached. An agreement from the town to cover 25 per cent of the project is required in order to release the first 30 per cent of the grant. Another 30 per cent will be made available if the project officially goes out to bid within nine months of the first milestone date. When the building is 75 per cent complete, as monitored by a project architect, another payment of 30 per cent is made, with the balance available on completion.