The Supreme Court on Thursday narrowed the scope of government-required environmental reviews for major infrastructure projects, overturning a lower-court block on a controversial rail line in Utah that would carry billions of gallons of oil. An array of challengers spent years battling over the 88-mile stretch of track that would connect the remote Uinta Basin in northeastern Utah to national rail lines, allowing the extraction of more waxy crude from one of the nation’s largest oil fields.

The case was closely watched because it became a proxy battle over how far federal agencies may go in assessing the environmental impact of highways, pipelines and other projects before deciding whether to approve them.

Justice Brett M. Kavanaugh announced the Supreme Court’s decision from the bench Thursday, saying judges should not micromanage agency decisions and that “overly intrusive judicial review” leads to “delay upon delay” and more expensive infrastructure projects. He said the landmark law at issue known as the National Environmental Policy Act (NEPA) is intended to “simply inform decision-making, not to paralyze it.”

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The court’s three liberal justices agreed with the outcome, explaining their separate reasoning in a concurring opinion written by Justice Sonia Sotomayor.

Justice Neil M. Gorsuch did not participate in the case.

Seven local counties and oil interests say the project would boost the region’s economy, which has been hampered by the lack of transportation options in a mountainous region the size of Maryland.

Those parties urged the justices to adopt a narrow reading of what impacts agencies must consider under the National Environmental Policy Act, the law that has set the standard for environmental reviews for about 50 years.

Five environmental groups and the county that is home to Vail, Colorado, opposed the project, saying it could have damaging environmental impacts across the United States.

The federal law, they argued, requires a more holistic review that should take into account that broader range of impacts, including the potential for oil spills in the Colorado review, habitat loss, pollution on the Gulf Coast where the oil would be refined and the project’s contribution to climate change.

Ann Marimow contributed to this report.