Sanford voters on Tuesday approved a $100.2 million high school and technical center that city and state officials say is the most expensive school construction project in Maine history.

While most of the project will be funded by the state, Sanford taxpayers will have a local share of about $10.6 million to build a new high school and new Sanford Regional Technical Center on a 127-acre parcel between Main Street and Route 4.

If everything goes according to plan, the high school and technical center would be ready for student occupancy in September 2018. The campus will feature an 830-seat performing arts center, a synthetic turf athletic field and outdoor bleachers.

Superintendent David Theoharides said the technical center is designed to educate high school-age students who are interested in fields such as automotive technology, nursing, welding, media production, cosmetology and firefighting.

Theoharides said there was virtually no public opposition to the project, largely because of the need for a new school to replace the aging and overcrowded high school, which was built nearly 50 years ago, and the fact that the lion’s share of the project will be funded by the state.

“We had a really strong grassroots effort behind this, a group of citizens that very much wanted this to pass,” Theoharides said Tuesday.

The group, Build Our Future, even held a pep rally last Saturday in support of the project. About 200 residents, including school band members, cheerleaders and Mayor Tom Cote, came to the Memorial Gym in Sanford in an effort to get out the “yes” vote. Jessica Jourdain, a member of Build Our Future, said the group also placed more than 200 lawn signs on properties throughout the city

The superintendent said the project should have no impact on the tax rate.

The owner of a home valued at $160,000 will actually see his annual property tax bill decrease slightly, largely because the school district will no longer have to lease 12 portable classrooms.

City Clerk Sue Cote released unofficial results late Tuesday from the special election. She said voters were presented with two ballot questions.

The so-called base project question asked voters to accept $92 million in state funds and to appropriate $7.9 million in local funds for a new high school.

The second supplemental project question authorized the expenditure of $2.7 million in local funds for sports infrastructure improvements.

Question 1 was approved by a vote of 2,311 to 688 while Question 2 was approved 2,058 to 931, Cote said.

Theoharides said the old school may be converted into an elementary school large enough to house students who currently attend the city’s four elementary schools.