Nearly everyone agrees I-70 winter ski traffic is terrible. But can data help the savvy traveler avoid the worst days?
We collected five years of winter weekend travel times from the Colorado Department of Transportation. By analyzing data that is not readily available to the public, we were able to identify some trends. Will the findings shave minutes off your ski commute? Maybe. But we're not making any promises.
Delays Happen At Very Consistent Times
Weather can always throw a wrench into I-70 travel times whenever it wants. But generally, I-70 winter weekend delays are caused by traffic volume. Skiers leave the Front Range and also return to it at remarkably regular times. For the stretch of road between C-470 (just outside Denver) and the Dillon exit that typically takes just under an hour to travel, we found the following trends.
- Significant Friday delays of greater than 20 minutes are most frequent between 5 p.m. and 9 p.m.
- Significant Saturday delays of greater than 20 minutes are most frequent between 6 a.m. and 11 a.m.
- Significant Saturday delays of greater than 20 minutes are most frequent between 4 p.m. and 8 p.m.
- Significant Sunday delays of greater than 20 minutes are most frequent between 11 a.m. and 7 p.m. (In other words, almost all day Sunday is a bad day to return to the Front Range.)
Eastbound Delays Are Consistently Worse On Sundays Than Saturdays
While Saturday evening delays are also a regular phenomenon as day-trippers head back down the hill, Sundays are more frequently delayed. Sundays also tend to have delays for longer stretches of time (see above). Sundays also tend to have longer overall delays.
Delays Are Far More Common In January And February
While ski season lasts until the end of March, delays in March are much less common than they are in January and February. Nearly every weekend in January and February had significant delays at some point. This was not true in December or in March.
Holiday Weekends Are Unpredictable
While travelers on Martin Luther King, Jr. day of 2011 experienced 172-minute travel times on the eastbound corridor between Dillon and C-470, the travel time for the same holiday in 2012 was a mere 94 minutes at its worst. In 2013, holiday traffic for MLK day only hit 72 minutes at the peak. (Expected travel time is 56 minutes).
The same holds true for President's Day. In 2015, travel time peaked at 142 minutes; the year before, at 82 minutes. There does not appear to be a consistent pattern on whether holiday long weekends always experience severe delays. Sometimes they do, other times not.
Travel Times Tend To Be Shorter When The Broncos Are In The Playoffs
Ryan Rice, an operations manager for the Colorado Department of Transportation noted that, anecdotally, I-70 winter weekend traffic volumes seem to ease during Broncos games.
"We often see traffic spike before the game and then there is lower traffic volume [during the game]," said Rice.
This chart shows travel times on Broncos playoff games compared to average travel times. And there does seem to be a Broncos effect.
So if you are not a football fan, traveling during a playoff game might be a good bet.