This is one of the most popular reef dive sites Oahu has to offer. The two open-ended lava tubes forms Makaha Caverns. The topography is flat and outside the cavern, the site spreads over a large area. There are pockets in the flat areas home to octopus, and several species of eels. The site also has turtles, transiting dolphins, and occasionally eagle rays. The colors of the corals at this site change dramatically at night, making it an exceptional place for night dives.
The Mahi is Oahu's most popular wreck dives and was originally sunk in 1982 as an artificial reef project, and is located about 15-minute boat ride from Waianae Boat Harbor. The Mahi was originally built as a minesweeper, but the Navy instead used the 800-ton ship in the Bahamas for laying cable. The Dillingham Corporation purchased the vessel in March 1968, and leased it to the University of Hawaii as a research vessel. Although originally sunk facing towards the shore, it now lies facing seaward. In 1982, Hurricane Iwa twisted the ships hull and spun it almost 160 degrees to its present bearing. Here you can find nudibranchs, eels, schools of fish, and schools of Eagle Rays.
LCU West Wreck
Divers often find white tip reef sharks hiding at the stern or the concrete blocks under the wreck. There’s also a good reef that’s just a short swim away.
This LCU rests on a sandy bottom 90ft down with the reef a little over 100’ away. Most divers swim over to the reef first, looking for interesting fish sightings. Divers good on air consumption can make it to the airplane wreck before having to turn around. The pilot house offers a tight but easy swim through.
Built in the early 1950's and sank as a artificial reef in 2007 this 15 meter Havilland plane was used by the Hawaiian Air Transport Service. Years later this plane was used in a Hawaiian Film called 'Flight 29 Down' in which its name was born. THis plane sits at 80 feet and you can find a variety of frogfish, eels, octopus, and turtles.
Land of OZ
This dive is known for its plentiful tubes and archways. The topography is amazing here. The reef formation runs parallel to the shore in 20-70 feet. A ravine runs along the shoreline and turns into a wall that drops to a cave at 65-70 feet. It has a variety of tropical fish, lobsters, and turtles. Immediately north, there are couple of sites with variations of the same topography as Land of Oz called Four Arches and Tube Two. These sites almost always have octopi if you look closely.
Black Rock / Ulua Cave
Black Rock is a wall dive from 40 feet stretching to 90 feet-deep with a large cavern approximately 100 feet long and 50 feet wide. One side of the room is collapsed allowing easy multiple entry and exit points. The adjacent wall takes you to a huge underwater cavern open on three sides. This cavern is home to white-tip reef sharks, turtles, and beautiful hard coral polyps living on the ceiling as well as spiny lobsters and Kona crab.
Directly off Poka'i Bay, lies a twin-engine Beechcraft. It was sunk as an artificial reef project and it lays within a horseshoe-shaped ridge at around 90 feet. Not much of the inside of the aircraft is still there except for the instrument panel. The top of the ridge is at a depth of 80 feet, which drops to a rubble base and then slopes to a depth of 110 feet. Within the cracks of the ledge you can find many crustaceans, tropical fish, and moray eels.