Westport’s share of the $305 million Diman Regional Vocational Technical High School project will decrease overall, following the select board’s 4-0 approval last week of a new plan that sees the state picking up a larger percentage of the project cost than was originally expected. Chairwoman Shana Teas did not attend.

Along with state funds, Westport is one of four towns that will fund the regional high school in Fall River, along with Swansea, Somerset and Fall River. Residents here voted at the 2022 Town Meeting to support what was then expected to be a $7.6 million local share; in April 2023, they voted again at the polls to fund that obligation via excluded debt, which allows borrowing without impacting the state-mandated 2.5 percent maximum levy increase per year and thus not impacting the yearly operating budget.

The town’s decreased liability comes even as the project, first expected to cost $293 million, has risen to about $305 million. Originally, the Massachusetts School Building Authority (MSBA) agreed to fund 51 percent of the project, leaving the other 49 percent to the four towns. But MSBA officials recently increased their state share to about 57 percent, adding an additional $22 million to its contribution and leaving the remaining 43 percent to the towns.

“After the project approval, we went into a period of really high inflation or escalation” due to Covid, supply chain issues and other economic factors, project architect Greg Joynt said. “Pretty much all project budgets from that time period ... were coming in over budget.”

However, he said, project officials made a commitment to the towns that they wouldn’t come back and ask for more money.

“This proposal stays true to that,” he said.

Instead of seeking additional local funding, project officials decided to start looking for savings, and were able to reduce the project’s scope to stay at the number approved by voters.

As cuts were made and scopes reduced, he said, MSBA officials concurrently “recognized that this inflationary period was outside of anybody’s real control. And so through legislative action they have been able to add money back in,” pledging to fund an additional $22 million of the project’s new cost.

When that happened, project officials started adding back in some of the features that had been cut, brining the total project cost to $305 million. But the overage, town administrator James Hartnett said, is being funded by the state’s $22 million funding increase and that will bring Westport’s liability down almost $700,000, to a total of about $7 million.

Monday’s vote does create some uncertainty, Hartnett said, because it is unknown whether state officials will approve of that additional $11.7 million going into towns’ excluded debt. He said Friday that Westport will request that the state Department of Revenue approve the changes so that all of the town’s costs will be categorized as excluded debt and thus will not impact the operating budget.

Worst case scenario, he said, Westport may have to pay $35,000 or so per year in project costs via the operating budget, which over the 30-year life of the town’s bonds would add up to roughly $900,000, he said — if the state does not approve excluded debt adjustments.

Regardless, Hartnett said, the project is a good deal for the town.

“I’m always concerned about the operating budget — we’re struggling for every penny,” he said prior to the vote. But “on the excluded debt side, (the town’s obligation) would actually go down a little bit. It’s an overall savings to the town.”

“It’s a good thing,” Hartnett added. “The project, and the reasons for doing it, are good.”