Gladstone water police at their busiest this weekend

TWO water police crews will inspect up to 800 boats over this long weekend.

Gladstone water police officer-in-charge Sergeant Jeff Barnett said it was their busiest time of year.

"It was disappointing on Wednesday night to start the season off with someone drink-driving while on their boat."

A 23-year-old man was pulling his boat out of the water when he was caught with a blood alcohol limit of .086.

"It's important to remind people even when they are anchored the same law applies. You can't be over .05."

He warned those unfamiliar with the harbour the banks may have changed.

"There will also be a high level of vessel activity and activities with the festival," he said.

"If you're not involved in the activities please just stay clear and be patient."