Water quality, snorkeling conditions & cliff-diving guide
📍 Kaʻanapali Beach, West Maui — Year-round snorkeling
Black Rock (Puʻu Kekāʻa) has excellent water quality year-round. The lava promontory and open ocean exposure provide strong natural circulation that keeps bacteria levels very low. This is one of the safest water quality ratings on Maui.
The primary swimming hazard is surge and current on the ocean-facing (north) side of the rock. Snorkel the protected southern face for the best and safest experience.
Stay out of the ocean for at least 72 hours after heavy rain. While Black Rock itself has excellent circulation, runoff from the resort area and Kaʻanapali beach can temporarily elevate bacteria in the surrounding water.
Black Rock is consistently ranked among Hawaii's top 5 snorkeling spots. The lava formations create complex habitat for marine life, and the calm protected waters on the Sheraton side make it accessible for all skill levels.
Hawaiian green sea turtles (hōnu) are frequently seen resting on the rocks or grazing in the area. They are a protected species — observe from at least 10 feet away and never block their path. The DOH recommends staying at least 6 feet from turtles.
Free alerts when water quality changes — brown water advisories, bacteria warnings, all-clear notices.
Safe to Swim Hawaii is an independent passion project — not affiliated with the Hawaii DOH. Ratings are estimates based on publicly available data and are not real-time measurements.
Always verify with the Hawaii DOH Clean Water Branch before entering the water.
When in doubt, don't go out. 🤙