Town of Superior v. Board of County Commissioners.
2026 COA 14. No. 25CA0836. Aviation Noise—Lead Exposure From Airport Operations—Federal Supremacy—Preemption—Injunctive Relief.
March 12, 2026
Rocky Mountain Metropolitan Airport (the airport) is located in, and owned and operated by, Jefferson County. The Town of Superior and the Board of County Commissioners of Boulder County (collectively, plaintiffs) sued the Board of County Commissioners of Jefferson County and Dahl, in his official capacity as airport Director (collectively, Jefferson County) for causing a public nuisance, seeking to enjoin touch-and-go operations by piston engine aircraft at the airport. Plaintiffs alleged that certain aircraft operations caused excessive noise and hazardous lead exposure for their residents. The district court dismissed the action on grounds of federal preemption.
On appeal, plaintiffs contended that the district court erred by concluding that their claim for injunctive relief was preempted by federal law governing aviation noise. They disputed the scope of federal preemption, maintaining that Jefferson County has authority as the airport proprietor to impose noise restrictions. Under City of Burbank v. Lockheed Air Terminal Inc., 411 U.S. 624, 638 (1973), state and local regulation of aircraft noise is preempted by federal law. And while an airport proprietor has authority to impose certain noise restrictions, a state court may not order it to do so because such an injunction would be an impermissible local control over aircraft noise.
As to plaintiffs’ lead pollution claim, the district court included it together with the noise claim in concluding that federal law preempts all state or local limitations on aircraft flight operations, including for noise or pollution. But City of Burbank is limited to federal preemption of state and local aviation noise control, so it does not resolve plaintiffs’ pollution-based claim. And the district court did not address Jefferson County’s argument in its motion to dismiss that the federal Clean Air Act preempts a ban on aircraft operations to abate lead emissions. The court of appeals declined to address this issue in the first instance.
The order was affirmed to the extent it dismissed plaintiffs’ request for an injunction to abate aircraft noise. The order was reversed to the extent it dismissed plaintiffs’ request for an injunction to abate lead emissions. The case was remanded for further consideration of whether the lead emissions portion of plaintiffs’ claim is preempted by federal law.