Boating Under the Influence: The Risks

Boating under the influence (BUI) is dangerous because alcohol and drugs slow your reactions, blur your judgment and throw off your balance, and the water makes every one of those effects worse. The U.S. Coast Guard says alcohol use is the leading known contributing factor in fatal boating incidents (opens in a new tab), and that BUI is just as deadly as drinking and driving (opens in a new tab).

The fix is simple: a sober skipper, and a plan for the day that doesn't need anyone to drive the boat after drinking.

What the numbers show

20%

The Coast Guard's 2024 report counted 244 boating incidents where alcohol use was the primary contributing factor, causing 92 deaths and 192 injuries (Recreational Boating Statistics 2024, Table 1 (opens in a new tab)).

CDC puts alcohol in the wider picture. Among teens and adults, it says alcohol use is involved in up to 70% of deaths associated with water recreation, like boating or swimming (opens in a new tab). These numbers measure different things, but they point the same way.

How alcohol affects people on boats

The Coast Guard says alcohol affects judgment, vision, balance and coordination (opens in a new tab). On the water, that means:

• Slower thinking. Cognitive abilities and judgment deteriorate, so it's harder to process information and make good choices.
• Clumsier bodies. Balance, coordination and reaction time all get worse.
• Worse eyesight. The Coast Guard lists decreased peripheral vision, reduced depth perception, poor night vision and difficulty in distinguishing colors (particularly red and green) (opens in a new tab), the colors of navigation lights and buoys.
• Disorientation in the water. The Coast Guard says inner ear disturbances can make it impossible for a person who falls into the water to distinguish up from down (opens in a new tab).
• A false feeling of warmth. Alcohol creates a sensation of warmth that may keep a person in cold water from getting out before hypothermia sets in.

The Coast Guard estimates that an operator with a blood alcohol concentration above .10 percent is more than 10 times as likely to die in a boating accident (opens in a new tab) than an operator with zero blood alcohol.

Sun, wind and motion make it worse

Alcohol hits harder on a boat. The Coast Guard says the marine environment, motion, vibration, engine noise, sun, wind and spray (opens in a new tab), speeds up a drinker's impairment. These stressors cause fatigue that makes coordination, judgment and reaction time decline even faster.

Experience matters too. The Coast Guard notes that boat operators are often less experienced on the water than on the road, and that boaters average only 110 hours on the water per year. It also says a boat operator is likely to become impaired more quickly than a driver, drink for drink.

There is no safe amount. The Coast Guard says there is NO safe threshold for drinking and operating a boat (opens in a new tab), and that medications and fatigue can make impairment happen even faster.

Passengers are at risk too

BUI isn't only about the person driving. The Coast Guard says that in boating deaths involving alcohol use, over half the victims capsized their boats and/or fell overboard (opens in a new tab), and that passengers are at greatly increased risk, especially if they've also been drinking.

That's why the Coast Guard's own advice is: having no alcohol while aboard is the safest way to enjoy the water (opens in a new tab). Intoxicated passengers are also at risk of injury and falls overboard. Read what to do if you fall off a boat.

Cold water raises the stakes. The National Weather Service says cold shock can cause involuntary gasping, rapid breathing or hyperventilating (opens in a new tab) the moment you hit the water. Alcohol makes it harder to respond.

BUI laws exist everywhere

The Coast Guard says it is illegal to operate a boat while under the influence of alcohol or drugs in every state (opens in a new tab), and that it also enforces a federal law against BUI. That law applies to all boats, from canoes and rowboats to the largest ships.

Its federal requirements guide says operating under the influence is a federal and state offense (opens in a new tab), and that the legality of a substance doesn't change the penalties. Penalties can include large fines, suspension or loss of boating privileges, and jail.

State laws differ in the details. NASBLA's state law dashboards (opens in a new tab) include reference guides on BUI and on whether a BUI can affect your driving privileges. This page is general safety information, not legal advice.

Plan a sober skipper

The Coast Guard suggests alternatives to using alcohol while afloat (opens in a new tab):

• Bring other cool drinks: water, sodas, iced tea, lemonade or non-alcoholic beer.
• Pack plenty of food and snacks.
• Dress to stay cool, and plan a trip length that avoids getting overtired.
• Party on shore instead. If alcohol is part of the day, the Coast Guard suggests having the party ashore, at the dock, a picnic area, a club or your backyard, with time between the fun and getting back in your car or boat.
• Wait if you've had a drink with a meal. The Coast Guard suggests waiting a reasonable time, estimated at a minimum of an hour per drink, before operating your boat.

And the basics for everyone:

• The operator drinks nothing. Agree on this before you leave the dock.
• Everyone wears a life jacket. See our boating safety checklist.
• No swimming after drinking. CDC says to avoid drinking alcohol before or during swimming, boating, or other water activities (opens in a new tab). See alcohol and swimming.
• Speak up. The Coast Guard says to call 911 or hail the USCG on Channel 16 if you see a drunk boater (opens in a new tab).

Young adults are at special risk. CDC's 2024 Vital Signs report notes that 25%–61% of persons aged 15–34 years (opens in a new tab) report alcohol use around water. Read water safety for college students and young adults.

What you can do today

1. Name your sober skipper for your next trip, and say it out loud to the group.
2. Stock the cooler with non-alcoholic drinks and plenty of water.
3. Plan any celebration on shore, after the boat is tied up.
4. Save Channel 16 and 911 as your "see something, say something" plan.
5. Share this page with the people you boat with.