North of Williamstad, the snorkeling at Black Sand Reef is known for good coral heads and diverse marine life.
In 1999, Hurricane Lenny passed near the island resulting in the first big waves in over 100 years. This wave action over a 24 hour period had a severe effect on the shallow water corals on west-facing coastlines. There was significant toppling of the massive coral colonies, along with bleaching and smothering. Similarly, in 2008, Tropical Storm Omar passed near the island producing heavy wave action along west-facing coastlines. The effects of these storm, along with occasional bleaching events, have left many of the snorkeling dive sites not appearing as they had in past photos nor seeming as described in the brief locally printed snorkeling dive descriptions, which tend to be older. While snorkeling off Curacao, you'll occasionally encounter some large, older coral formation remnants that give clues to the size of the past reefs. And, you may notice some small new growth occuring along the sand flats where new coral is taking hold in the cemented coral rubble, especially quick growing fire coral. Overall, there are 57 coral species providing habitat for over 500 fish species.
Overall, Black Sand Reef is the 8th most popular snorkel dive spot of all 13 snorkeling dives in Curacao.