Lafayette Parish voters will make a major decision this spring that has a direct impact on 30,000 of the parish’s residents — the majority of whom aren’t old enough to vote.

A property tax increase totaling 16 mills will be on the April 9 ballot, with 11.5 mills dedicated to school construction and facility improvements. The millage will generate about $380 million to fund major construction projects on campuses, according to school system officials.

While the School Board plans to confirm in the coming weeks what projects will be funded by the proposition, staff has suggested spending nearly $200 million on construction to replace existing campuses that planning experts have identified as priority projects.

The projects on the draft list include addressing outdated and overcrowded campuses at Lafayette High and Carencro Heights Elementary, as well as continuing construction to replace facilities at L.J. Alleman Middle and Katharine Drexel Elementary in Broussard.

At Alleman, a prior bond sale helped pay for a larger auditorium-cafeteria for the middle school that serves both as a neighborhood school and a performing arts academy for students across the parish. About $50 million is suggested to be spent at Alleman to continue those improvements and to replace other existing classrooms and buildings.

The largest chunk of the funding — $115 million — is estimated to be used for the replacement of Lafayette High — the largest school in the parish and the state, based on its current enrollment of nearly 2,500 students. The proposed draft of projects also addresses the other high school campuses — with $60 million for expansions at Northside, Carencro, Comeaux and Acadiana — to replace portable buildings.

Carencro Heights Elementary is marked for a complete replacement, as well, at an estimated cost of $26 million.

The list includes $9 million for a second phase of construction at Drexel Elementary for additional classroom space. Construction at Drexel has not started, but the first phase of construction to eventually replace the school — estimated at $32 million — is part of a $126 million bond sale the board recently approved. The bulk of the $126 million bond package is being used to pay for the new high school in Youngsville.

School Board Vice President Dawn Morris said the board will decide in early 2016 which projects will be included in the millage proposition via resolution. While it’s not possible to list the projects on the ballot due to state election rules, the proposition on the ballot will reference the resolution where the board-approved projects will be listed, she said.

“That list will be referenced in the tax proposal that voters will see,” Morris said. “If Project 3 doesn’t get built, then that money can’t get used for anything else. The listing comes through the master facilities plan put in place a few years ago with quite a bit of community involvement.”

The master facilities plan was adopted by the board in 2010 and used to create a proposition to fund about $560 million in construction projects, including a replacement facility for Lafayette High — but voters rejected that proposal in fall 2011.

In addition to the school replacement projects, staff also has proposed $20 million for security upgrades to campuses across the district; $44 million to complete construction at the new high school for additional classrooms, a fieldhouse and auditorium; $14 million for new classroom wings at Broussard Middle; $12 million for HVAC upgrades or replacements and air conditioning for all school gyms; and $30 million for major renovations at the W.D. and Mary Baker Smith Career Center.

Follow Marsha Sills on Twitter, @Marsha_Sills.