Diving & Snorkeling
Boaters and divers have a shared responsibility. Boaters must watch for and avoid dive flags (slow no wake within 200 feet) and divers must mark their positions with a dive flag. At night, a dive flag must be illuminated and visible from 100 feet.

Diving & Snorkeling
Any underwater activity—snorkeling, SCUBA, free diving—requires a red and white diver’s flag when in progress.
Dive Flag Requirements (HAR 13-245-9)
- Vessels ≤16 feet: 12″ x 12″ flag, visible from all directions
- Vessels >16 feet: 20″ x 24″ flag, displayed at highest point
- Night diving: flag must be clearly illuminated and visible from 100 feet
Proximity Rules:
- Divers must surface within 100 feet of the flag in ocean waters and 50 feet in streams.
- Other vessels may not approach within these distances unless diving and must do so at slow-no-wake speed.
Additional Rules:
- Do not display dive flags unless diving is in progress.
- Diving or swimming in navigation channels is prohibited, except in emergencies.
- Diving may not unreasonably interfere with navigation.
This page was last updated on 09.12.25
