Leading Cause of Boating Deaths Alcohol is the leading cause of boater deaths and was responsible for a whopping 20 percent of boating accidents in Colorado last year, but it seems most boaters don't realize drinking on the water is more dangerous than drinking on land. This is because the rocking motion, strong sun, wind and spray all accelerate impairment and fatigue, making one more susceptible to poor navigation, falling overboard, hypothermia, and drowning. BUIs, therefore, are treated just as seriously as DUIs. Similarities In some ways, the laws for drunk driving and boozy boating are identical. A boater is considered legally intoxicated when his blood alcohol content (BAC) reaches 0.08 percent; a zero-tolerance policy is in effect for minors; and a boating license comes with "implied" consent for alcohol testing. A BUI could also count towards your overall tally of drunk-driving offenses, so expect greater penalties if it follows a traditional DUI or vice versa. Restrictions Unlike automobiles, however, open containers of alcohol are acceptable on water vessels--though, of course, there's a catch. Only 3.2 percent alcohol is allowed in Colorado state parks (guardians of most lakes and rivers), which is essentially light or malt beer. Wine, whiskey, and winsome summer cocktails simply won't make the cut as you kayak along Confluence Park, and neither will kegs or glass containers. Marijuana and Boating Combining marijuana and nautical activities is a whole other story. Cannabis isn't allowed in public, so smoking, ingesting, or vaporizing the drug while on a boat (regardless of whether you're the driver or a passenger) is absolutely forbidden. Unless you're canoeing in your friend's backyard pool, leave the weed at home. Also bear in mind that Colorado's recreational marijuana laws do NOT apply in national parks and on federal lands, such as Lake Granby or Lake Estes. If you smoked pot the night before and are found to be stoned while paddling through these waters the next morning, Colorado law will not protect you. Remember, marijuana is still illegal in the eyes of the federal government. ALL WATERCRAFT Incidentally, Colorado's BUI laws changed in 2008 to include ALL WATERCRAFT operated by "motor, wind, paddle, and oar, such as jet skis, sailboats, motorboats, kayaks, canoes, and rafts." In other words, you're eligible for a BUI even if your vessel doesn't have an engine. Federal Regulation One last thing in case you're seafaring outside of Colorado, the U.S. Coast Guard enforces a federal BUI law, which pertains "to ALL boats (from canoes and rowboats to the largest ships)--and includes foreign vessels that operate in U.S. waters, as well as U.S. vessels on the high seas."