The Colorado Supreme Court on Monday dismissed an aircraft noise violations case against Denver International Airport that had prompted a lower court to award $33.5 million to Adams County and other plaintiffs.
The high court concluded that Adams County’s 2018 lawsuit against DIA was filed 20 years too late. The county and other participating communities, including Aurora, alleged that the airport had been underestimating its noise impacts on surrounding neighborhoods for years by using a method that violated an inter-county agreement.
By rejecting the breach-of-contract claim, the 6-0 opinion overturned a 2020 district court judgment against DIA that had accrued enough interest to nearly double its $33.5 million value, according to an airport financial report. In 2022, the Colorado Court of Appeals upheld the judgment.
In its 38-page ruling, the Supreme Court conceded that DIA breached a 1988 intergovernmental agreement with Adams County that required the airport to use a “noise-monitoring” system to report noise levels produced by aircraft using the facility. Instead, DIA used a “noise-modeling” system that estimated noise levels.
But the court concluded that Adams County was aware of DIA’s violation of the agreement as far back as 1995, the year the airport opened. It had three years under the state’s statute of limitations to file a complaint.
“But it sat on its rights until 2018,” Justice Carlos Samour wrote for the court. “By then, it was too late.”
Replete with playful aviation-themed language, the opinion speaks to the high court’s “takeoff point” in its analysis of the case and characterizes the court as being “piloted” by state law to arrive at its ruling.
“Next, we follow the prevailing common-law winds and boost our statutory analysis with our case law and federal decisions applying Colorado law,” Samour wrote. “We proceed by explaining that prudent public policy considerations justify our course.”
Finally, the opinion states that the justices “land at the conclusion that Adams’ breach-of-contract claim is time-barred.” Justice Maria E. Berkenkotter didn’t participate in the court’s consideration of the case.
The court found that the statute of limitations applied to the moment the county first became aware that the 53-square-mile airport — occupying land that used to belong to Adams County — was using the wrong system to measure noise. It didn’t matter that Adams County had not quantified the harm from aircraft noise violations to surrounding communities until many years later, the court said.
“In sum, the proverbial clock started ticking no later than 1995, as Adams undisputedly knew then that Denver was using a modeling system instead of a monitoring system, in contravention of the IGA,” the court’s opinion says.
A spokeswoman for the county declined to comment Monday afternoon.
Everett Martinez, the general counsel for DIA, said that not only was the original $33.5 million judgment from a Jefferson County District Court judge wiped away by Monday’s ruling, but millions more in interest that had accrued were also overturned.
He estimated the current judgment value at “nearly $50 million,” but it may be even higher. The airport’s annual financial report for 2022, its most recent, valued the judgment plus interest at $57.6 million as of Dec. 31, 2022.
“The Colorado Supreme Court correctly recognized that this long-running lawsuit should have been dismissed years ago because the claims asserted in the case are not legally valid,” Martinez said. “We are grateful that (the judgment) has been overturned and we can put this litigation behind us.”
At the heart of Adams County’s complaint was the contention that the airport relied on a noise modeling approach that was never tested for its accuracy in terms of how it compared to actual noise data collected on the ground. In its 2018 suit, it described the system “as being an outdated, archaic aircraft noise modeling system” that was “abandoned years ago by all users except DIA.”
The suit went further, saying Denver “actively kept secret any data or evaluations of the data” produced by its system.
Thornton, Aurora and Brighton joined Adams County in the legal challenge. Their case cited noise violations by airplanes flying over long-established neighborhoods west and south of the airport from 2014 through 2016.
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