The Denver Regional Transportation District (RTD) often markets itself as a green solution to traffic congestion and climate change. In reality, RTD uses more energy and emits more greenhouse gases per passenger mile than the average car, and even the average SUV.
In 2019, RTD consumed 4,340 BTUs and emitted 287 grams of CO2 per passenger-mile. That was worse than both the average car (2,800 BTUs; 197 grams) and light truck (3,265 BTUs; 231 grams). By 2023, RTD’s energy use climbed to 5,400 BTUs per passenger-mile, with emissions reaching 319 grams.
This raises a tough question: Is RTD really “green,” or just financially wasteful?
According to RTD’s own financial records, its operating budget increased by nearly 60% between 2021 and 2023, growing from $629 million to over $1 billion. Yet ridership is shrinking. Since 2022, total rail boardings have dropped by nearly 10%, and light rail boardings alone have fallen more than 18%, from 13.6 million to 11.1 million. Farebox recovery—the portion of its budget covered by passenger fares —has fallen below 5%, meaning riders pay just five cents of every dollar the agency spends. Taxpayers cover the rest.
Despite claims of reducing congestion, the opposite has happened. Since voters approved the $7.2 billion FasTracks plan in 2004, congestion has worsened. According to the Texas A&M Transportation Institute, Denver commuters spent 66 hours in traffic in 2022- up from 50 hours in 2004.
RTD’s Impact across metro Denver is minimal. In Douglas and Jefferson counties, transit usage among workers is below 1.5%. In Broomfield, it rarely exceeds 2%. Even in Arapahoe County, home to the job-rich Denver Tech Center, just 2.1% of workers take transit to their jobs. These aren’t just census numbers, they’re a wake-up call.
RTD also contributes significantly to emissions. Its 2019 sustainability report cited 185,000 tons of CO2, 60% of it from diesel and gasoline. And though RTD’s trains run on electricity, generating that power creates emissions. In 2023, Colorado power plants emitted 1.054 pounds of CO2 per megawatt-hour. That means light rail trains effectively emitted 371 grams of CO2 per-passanger-mile-higher than the average car. Commuter rail trains emitted around 180 grams, about the same as cars.
RTD argues that it offsets this by removing cars from the road, estimating 240,000 tons of CO2 avoided per year. However, this assumes that every rider would otherwise drive solo, and it ignores the emissions from running near-empty buses and trains.
RTD and its supporters like to claim that public transit is inherently green, as well as efficient and equitable. But the data tells a different story. Despite billions of dollars in spending, the Denver metro region’s percentage of people who use public transit to get to work hasn’t budged, holding steady at 4.8% from 2000 to 2019. Even with five new rail lines and flashy new stations from the FasTracks spending spree, congestion has not declined, and neither have car commutes.
If RTD wants to be a part of a sustainable future, it needs to earn that role. That means publishing energy-per-rider data, reallocating service to high-ridership corridors, and eliminating underperforming routes. Until then, we should stop calling RTD “green” just because it runs on rails.
Ethan Cornell is pursuing a master’s degree in natural resources and energy policy at Colorado School of Mines, and is a recent graduate of the Future Leaders Program at Independence Institute, a free market think tank in Denver.

