Bonaire is surrounded by a reef. On the leeward (or west) side of the island, you can literally walk into the water and start snorkeling. The waters are now protected and have been declared a marine sanctuary.
While I was in Bonaire there was a storm surge somewhere in the ocean which made the surf choppy and the reef a bit cloudy. Evidently this side of the island is usually incredibly clear and there are very few waves.