

Best for intermediate divers, 9-30m, boat entry, mild current.
Semakai Reef in Yap offers a combination of reef structures and a wall, suitable for drift diving. The site ranges from 9 to 30 metres in depth, with an average of 20 metres. Visibility typically spans 15 to 30 metres, and water temperatures remain consistent between 28 and 30 degrees Celsius. Divers should expect mild currents, though surge can occur. The site is accessible by boat and supports night diving. Hazards include lionfish, stonefish, sharks, and surge. Divers should monitor depth gauges and maintain awareness of reef structures to avoid entanglement. The habitat supports a variety of reef fish and invertebrates typical of the region.
9.50620, 138.17557
Check current conditions locally before your dive, as surge and swell can pick up and affect entry and exit from the boat. Boat operators should be able to advise on the best drift direction for the day.
Boat access is required for this reef site.
Recorded at this site
Depth
9-30m
Visibility
15-30m
Skill Level
Intermediate
Entry
Boat
Boat required
Water Temp
28-30°C
Current
Mild
Typical Dive
60 min
Best Time
Jan, Feb, Mar, Apr, Nov, Dec
The reef habitat supports a variety of regional reef fish and invertebrates.
Semakai Reef is rated for intermediate divers due to the drift conditions and potential for surge.
The site depth ranges from 9 to 30 metres, with an average depth of 20 metres.
Access to Semakai Reef requires a boat.
This site is primarily designated for diving; check with local operators regarding snorkel suitability given the drift and depth profile.
Diving at Semakai Reef in Colonia requires the following certifications: Open Water. Always dive within your training limits.
A rashguard or 2mm shorty is recommended for diving at Semakai Reef in Colonia. Water temperatures range from 28°C to 30°C.
The best months to visit Semakai Reef in Colonia are January, February, March, April, November, and December. Conditions outside these months can still be good but are less predictable.
Divers at Semakai Reef in Colonia should be aware of lionfish, stonefish. These encounters are generally rare and avoidable with proper awareness. Follow local safety guidance and maintain a respectful distance from all marine life.
Semakai Reef in Colonia typically has mild currents that most divers can handle comfortably.
Visibility at Semakai Reef in Colonia typically ranges from 15 metres to 30 metres. Conditions vary with weather, tides, and seasons.