PORTLAND, Maine — Voters approved the city’s share of a $101.6 million school budget in a referendum Tuesday, 1,033-459.

The city’s portion, $96.3 million, will increase property tax revenue to the school department by 2.5 percent, or about $25 per $100,000 of assessed property value. For a median-value home of nearly $242,000, the tax increase will be about $60 per year. About $5.3 million of the school budget will be from other sources.

The fiscal 2015 school budget is a 3.5 percent increase over this year’s $98.2 million total spending plan.

Voter turnout was low, with 1,492 residents going to the polls in 12 locations, or about 2 percent of the city’s more than 52,500 registered voters. In last year’s school budget referendum, 2,265 voters participated.

City Clerk Katherine Jones said this year’s referendum cost the city about $20,000 for advertising expenses, payroll for election officials and printing ballots. That comes out to $13.40 for each vote.

In voting Precinct 1-2, six election officials sat all day in a nearly empty room at Merrill Auditorium Rehearsal Hall. At 7:45 p.m. Tuesday, Election Warden Carol Morrisette said 33 voters had cast ballots. Most of them didn’t know the referendum was being held, she said, until they saw a “Vote” sign on Myrtle Street.

One of those voters was David Bridge, who cast a ballot in favor of the budget after asking election officials about the nature of the referendum. When he learned how few people turned out for the vote, he said he was disappointed.

“It’s just gross,” he said. “It’s disgusting.”

In Precinct 5-2, Deputy Registrar Delene Perley registered one new voter during her six-hour shift Tuesday afternoon. She said the day was very quiet; with slightly more than 100 voters, she spent most of her time reading a book.

Holding the referendum in May is a “waste of money,” Perley said, especially when the primary election is less than a month away.

“It seems silly,” she said. “You’d think somebody would be able to work this out somehow.”

This year’s budget process was also notably quiet. During an April meeting, several members of the School Board speculated on the possible reasons.

School Board Chairwoman Sarah Thompson said the muted public response indicated that the board had gained the public’s trust. Board member Marnie Morrione said the district’s efforts to involve the public through a community forum and an online budget “tool kit” helped ease the process.

Board member Justin Costa had said this year’s budget reflects a stronger economy. The school department struggled for several years after the recession, he said, but the new budget marks a turning point.

The 2015 school budget is about $600,000 less than originally proposed by Superintendent Emmanuel Caulk on March 11. The reduction is due to a decrease in anticipated health care premiums for district employees, from 8 percent to 2.5 percent.

Caulk thanked voters Tuesday night in a news release.

“This budget will allow us to retain all staff in locally funded positions and to focus on our four priorities: strengthening the core academic program, stimulating progress for all learners, driving innovation and investing in infrastructure,” Caulk said.