How much alcohol, compared to the amount that makes a person legally intoxicated on land, can impair a person on the water?

The amount of alcohol that can impair a person on the water is significantly less than what would be required to be legally intoxicated on land. This is because various factors can affect a person's ability to function while boating, such as the environmental conditions, physical exertion, and sun exposure, all of which can amplify the effects of alcohol.

In general, on the water, a person may experience impairments at about one-third of the legal intoxication level compared to being on land. This means that even a smaller amount of alcohol can affect their cognitive and motor skills, making it unsafe for them to operate a vessel. The effects of alcohol can be magnified by the stress of operating a boat and navigating on the water, which requires heightened awareness and quick reactions.

The other provided amounts are not as accurate because they suggest higher thresholds that do not take into account the unique conditions that boaters face. Therefore, understanding that a lower amount of alcohol can lead to impairment emphasizes the importance of responsible drinking while participating in water activities.