Chapter 4: The Legal Requirements of Boating
Alcohol and Drugs

Colorado law prohibits anyone from boating under the influence (BUI)—that is, operating any vessel propelled by a motor or sail, or manipulating water skis, aquaplanes, or similar devices, while under the influence of alcohol, a controlled substance, any drugs, or any combination of these substances.

Alcohol and drugs cause impaired balance, blurred vision, poor coordination, impaired judgment, and slower reaction time. Alcohol contributes to about one-third of all fatal boating accidents nationwide. Read more about the effects and risks of consuming alcohol.

• Colorado law states that a person is considered to be boating under the influence (BUI) if he or she:
  • Has a blood or breath alcohol concentration of 0.10% or greater or ...
  • Is under the influence of alcohol or ...
  • Is under the influence of any controlled substance, any other drug, or any combination of these substances that renders him or her incapable of operating safely.
• The penalty for a first conviction of boating under the influence is mandatory jail time of at least 5 days, not to exceed 180 days. A fine of $100 to $1,000 also may be added by the court but is not mandatory. The convicted person also will lose operating privileges for three months.
• By operating a vessel on Colorado waters, you have given “implied” consent to alcohol testing if directed by an arresting officer having reasonable grounds to believe that you are boating under the influence. Refusal to submit to alcohol testing will be admissible into evidence at trial.
• It is illegal for the owner or operator of a motorboat or sailboat to knowingly permit the vessel to be operated by someone under the influence of alcohol, a controlled substance, any other drug, or any combination of these substances that renders that person incapable of safely operating the vessel.

The best thing you can do for your safety and the safety of your passengers and other boaters is simple—Don't drink and boat!

Areas of Impairment Due to Blood Alcohol Concentration (BAC) Because you can drink faster than your system can burn off the alcohol, there is an increasing level of alcohol in your blood. This level is referred to as Blood Alcohol Concentration (BAC).