BOATsmart! Base de connaissances du Canada 

Boater fatigue

This negative effect is caused by a combination of the hot sun, wind, noise, vibration and the motion of the boat. These factors can quadruple the effects of alcohol on boaters. What’s more, alcohol also slows your swallowing and breathing reflexes, making you more likely to drown if you fall overboard.

Dehydration

Heat and sun can cause dehydration as the body tries to cool itself by sweating. If you’re dehydrated, you will feel the effects of alcohol more quickly. Even mildly dehydrated people will absorb alcohol more quickly into their system and will have a higher blood alcohol concentration than a non-dehydrated person. Dehydration causes the body to lose fluids, which can lead to stomach cramps while attempting to swim and stay above water.