Voters approved a $1.4 billion bond sale to refurbish and expand the aging, overcrowded school system in Midland, Texas, the unofficial shale-oil capital of the US, preliminary results show.

The school spending package — the largest ever in the district’s history — was approved by a 56%-to-44% margin Tuesday, according to the Midland County website.

The initiative had backing from many of the area’s biggest oil companies, including Chevron Corp., Diamondback Energy Inc. and Pioneer Natural Resources Co., which Exxon Mobil Corp. is buying in its largest takeover in more than two decades.

The drillers and others donated hundreds of thousands of dollars to back the bond proposal, which they said would help attract families and alleviate labor shortages in the region.

Midland, like countless Texas municipalities, is outgrowing its infrastructure as companies expand their presence in the Lone Star State. A lucrative fracking industry in the Permian Basin — which pumps about 46% of the country’s oil — requires a large, skilled workforce that’s hard to retain given the sorry state of small-town hospitals, roads and educational systems.

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Although there’s little debate facilities in the 29,000-student Midland Independent School District are in bad shape — 40% of schools are overcapacity with the district expecting to enroll about 400 new students every year — the bond’s price tag garnered criticism. Residents rejected a much smaller school-improvement proposal in a nail-bitingly close 2019 vote, when inflation hadn’t yet hit and construction costs were significantly lower.