The busiest weekend of ski season closed out one of the slowest Decembers in recent history on I-70 and the slowest year since 2021.
Nearly 124,000 cars traveled the Eisenhower-Johnson tunnels this past Friday into Sunday, Dec. 26-28, the busiest weekend of the month by nearly 5%.
One busy holiday weekend could not salvage a month’s worth of below-average traffic, when I-70 barely broke 441,000 cars in four weekends for a 12% decline from last December. That is the biggest year-to-year loss since the pandemic shutdown of 2020, when cars were forced off the roads.
Looking back on the entire year, a grand total of 6.4 million cars traveled I-70 on weekends only, down 4% from last year and the smallest annual total since 2021, when people were just starting to remerge from pandemic shutdown. Only three months this year saw more traffic than last year in January, April and November.
I-70 weekend traffic in 2025 (vs 2024)
- 39,839 vehicles… average daily traffic (down 3.5%)
- 484,755 vehicles… average monthly traffic (down 2%)
- 6,404,102 vehicles… annual traffic (down 4%)
- 147,009 vehicles… Aug. 8-10, busiest weekend (down 4%)
- 80,646 vehicles… Oct. 31 to Nov. 2, slowest weekend (up 3%)
- 560,900 vehicles… July, busiest month (down 5%)
- 397,745 vehicles… November, slowest month (up 8%)
- 12%… year-over-year loss in December
So what happened on I-70? Construction is partly to blame. The two largest projects in CDOT history, the $905 million rebuild at Floyd Hill and $325 million auxiliary lane expansion at Vail Pass, scared drivers off the corridor before they even got on it.
Curiously, the slowest months and weekends of this year were busier than last year, but that is where weather and I-70 closures come into play. Look at November, which was the slowest month in both years. There were no major storms or closures this November, unlike last year, when commercial trailers were banned and two major storms closed the interstate multiple times, bringing a record 100+ inches of snow to Copper Mountain.
Although not to blame for shrinking traffic, shifting patterns disrupted the corridor this year. Traffic heading east out of the mountains always tends to be busier than traffic heading west into the mountains, but eastbound traffic was busier than westbound traffic by 7% this year – three times higher than average.
