Chapter 4: The Legal Requirements of Boating
Alcohol and Drugs

South Dakota law prohibits anyone from boating while intoxicated—that is, operating any vessel while under the influence of alcohol or drugs. Alcohol and drugs cause impaired balance, blurred vision, poor coordination, impaired judgment, and slower reaction times. Alcohol is a major contributor to boating accidents and fatalities. Read more about the effects and risks of consuming alcohol in Chapter 5.

South Dakota law states that a person is considered to be boating under the influence (BUI) if:

• The alcohol concentration in his or her blood or breath is 0.08% or more or…
• The person is under the influence of alcohol, any other drug, or a combination of drugs and/or alcohol to a degree that makes him or her incapable of safely operating the vessel.

By operating a vessel on South Dakota’s waters, you have given “implied” consent to alcohol and/or drug testing if requested by a law enforcement officer. Refusal to submit to testing is admissible as evidence in court.

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).