A bid to stop plans to close 25 libraries, and hand over several more to be "community-run" by volunteers, has failed.
At an extraordinary meeting of Essex County Council an amendment was passed which did not rule out closures, but agreed to explore using libraries as community hubs.
The council said it needs to "bring libraries into the 21st Century".
Opponents have described the plans as "an act of cultural vandalism".
Along with the plan to close 25 libraries, of the 49 which would remain, it is proposed that 19 are run by community groups, 15 are proposed to be managed by the council in a partnership and a further 15 will remain managed solely by the council.
The meeting had been called after more than 57,000 signatures were gathered for a petition opposing the changes, which would take effect by 2024.
The original motion at the meeting, tabled by Liberal Democrat group leader Mike Mackrory, called for the cabinet to rule out any closures, but an amendment by the Tory group was voted through.
Susan Barker, cabinet member for libraries, said there had been 49 expressions of interest from communities wishing to run libraries.
She said: "We do want to keep all libraries open as community hubs but the status quo is not the way to do that. Usage is falling off.
"We want to regenerate our libraries, to bring them into the 21st Century, to revive them."
Mark Cory, Colchester Borough Council's Liberal Democrat leader, said: "It is such a threat to the social fabric of the whole county, these are the last bastions of public service in the town where you can go and get books, free internet and other services."