CDOT prepares for 100 Deadliest Days of Summer

Blue lights on the top of a police car at night

Courtesy of Colorado Department of Transportation

Warm weather fun has officially begun, and the Colorado Department of Transportation is urging motorists to travel safe this summer. From May 16 to June 5, CDOT will support the Colorado State Patrol and 72 local law enforcement agencies for The Heat Is On Memorial Day DUI enforcement period. During the 21-day enforcement period, drivers may see saturation patrols, sobriety checkpoints and additional law enforcement officers on duty dedicated to arresting impaired drivers. If your holiday weekend plans include alcohol or cannabis, planning a sober ride is always the best way to avoid a DUI.

Memorial Day marks the start of the 100 Deadliest Days of Summer — the period between Memorial Day and Labor Day that historically sees a spike in fatal crashes. From 2019 to 2023, there were 54 impaired driving related fatalities during the 100 Deadliest Days of Summer. Additionally, 2,295 DUI arrests were made during CDOT’s summer enforcement periods last year.

CDOT also began the Click It or Ticket May Mobilization seat belt enforcement period on May 13. This 20-day period is the largest seat belt enforcement of the year.

“As the days get longer and Coloradans attend more parties and social events, it’s important to remember that impaired driving can ruin lives,” said Col. Matthew C. Packard, chief of the Colorado State Patrol. “Colorado lost 218 lives to impaired driving in 2023. These deaths were preventable. Don’t put yourself and other motorists at risk this season by driving impaired.”

There were 479 reported DUI arrests over last year’s Memorial Day Weekend enforcement period. Alcohol impairs your ability to concentrate while driving and increases your risk of a crash. To stay safe, never drive if you’re under the influence of alcohol or cannabis, wear your seat belt and set your phone on Do Not Disturb mode. Remember: buzzed driving is drunk driving and can result in a DUI.

“Leave the driving to the sober this Memorial Day weekend. Always plan a sober ride home before going out so you won’t be tempted to later drive impaired,” said CDOT’s Office of Transportation Safety Director Darrell Lingk. “A DUI will ruin your summer fun and a crash could cost you your life. Never get behind the wheel if you are impaired.”

If you’re hosting a gathering this Memorial Day weekend, make sure your guests stay safe by following the tips below:

  • Encourage your guests to designate a sober driver or plan to use a ride-sharing service, taxi or public transportation.
  • Provide plenty of food and non-alcoholic drink options and encourage your guests to stay fed and hydrated throughout the party.
  • Offer guests a place to stay if a sober ride home is unavailable.
  • Remember, as a host, you could be held liable if a guest you serve alcohol to gets in a crash.

The recent Spring Events DUI enforcement period concluded with 506 arrests across 81 participating agencies. The agencies with the highest arrests were Denver Police Department (65), Colorado Springs Police Department (55) and Aurora Police Department (36). Following Memorial Day, the next DUI enforcement period will be Summer Blitz from June 8 to 21.

For yearly impaired-driving crash and fatality data in Colorado, visit For local law enforcement agency plans, visit

About The Heat Is On

The Heat Is On campaign runs throughout the year, with 16 specific high-visibility impaired driving enforcement periods centered on national holidays and large public events. Enforcement periods can include sobriety checkpoints, saturation patrols and additional law enforcement on duty dedicated to impaired driving enforcement. Find more details about the campaign, including impaired driving enforcement plans, arrest totals and safety tips at More information about DUI laws in Colorado can be found at Learn more about CDOT’s dedication to keeping Colorado roads safe, including impaired driving enforcement objectives, arrest data and safety information at