Library hours across Lincolnshire are to be cut significantly, according to draft council proposals.
Figures obtained by BBC Radio Lincolnshire show the county council intends to reduce the opening hours at 21 of 47 libraries.
Officials said the decisions were based on information gathered as part of a public survey carried out in 2007 into library usage.
But some councillors said they feared this was a step towards closures.
Councillor Amarylis Midgley from Woodhall Spa said the hours at her local library were being reduced but it would be open on two evenings.
She said: "The one evening a week the library's open at the moment, it's hardly used at all.
"As far as we can see, reducing the hours and putting them on when people don't want to use them is a recipe for future closure."
But Mark Homer, director of culture and adult education at Lincolnshire County Council, said the proposals were aimed at improving the library service.
"One of the key finding's in last year's report was that people did use more than one library and were willing to travel up to 12 miles to a major library and up to six miles for a smaller one.
"We are making the service fit-for-purpose in terms of what the broader community needs are, rather than just exclusively being influenced by existing users."
He added the plans were still at the draft stage and no final decisions had been reached.