Oʻahu · United States · Wreck
The Mahi
WWII minesweeper on sand, deck at 18-24 m
Area photo: mattk1979 · CC BY-SA 2.0
A wartime Admirable-class minesweeper that finished as a university research ship and was sunk about a mile off Waianae in 1982. She lies on sand at 27-29 m with her deck between 18 and 24 m, schooled over by bluestripe snapper, and eagle rays are common around her.
Also known as MS Mahi, USS Scrimmage.
Where it is and how deep
21.4380° N, 158.2060° WPublished position for this site.
The dive
The ship sits on sand in 27 to 29 m of water with her deck between 18 and 24 m, so the dive works from the top down: the superstructure first, then the deck line, then the sand along the hull if the plan allows. Hurricane Iwa turned her 180 degrees shortly after she was sunk in 1982, which is worth knowing before you try to read her heading against the shore.
Large schools of bluestripe snapper hold on and around the wreck and are the first thing most divers notice. Eagle rays are common over the sand, monk seals do visit, and eels and frogfish are both regular finds for anyone working the plating slowly. She is about 53 m long (175 ft), so a single dive covers her comfortably without hurrying.
The wreck
- Vessel
- MS Mahi (ex-USS Scrimmage, AM-297)
- Type
- Admirable-class minesweeper, later a research ship
- Length
- 53 m (174 ft)
- Built
- 1943
- Sunk
- 1982
- Cause
- Sold to Dacor Scuba Diving and sunk as an artificial reef off Waianae
- Lies
- On sand in 27-29 m with the deck at 18-24 m; Hurricane Iwa turned her 180 degrees soon after she went down
She was laid down as USS Scrimmage in February 1943, launched that May and commissioned in April 1944, and her crew came home from the Pacific with six battle stars. Sold out of the Navy, she became the British merchantman MV Giant II and worked as a cable ship, then in 1968 went to the Dillingham Corporation and was leased to the University of Hawaii as the research vessel MS Mahi. Dacor Scuba Diving bought her in 1982 to sink as an artificial reef. A US flag has been raised on her mast for Memorial Day since 2008.
Marine life and season
- Eagle rays
- Reef fish swarms
- Seals & sea lions
- Frogfish
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Good | Good | Good | Good | Prime | Prime | Prime | Prime | Prime | Prime | Good | Good |
Season follows Oʻahu: South-shore boat diving runs all year; the North Shore reefs at Pupukea are only calm from about May to October and are dangerous in winter.
Questions divers ask
How deep is the Mahi wreck?+
She lies in 27 to 29 m of water with her deck between 18 and 24 m, so most of the dive is spent above 24 m. Advanced training is the comfortable level for it.
What was the Mahi before she was sunk?+
USS Scrimmage, an Admirable-class minesweeper commissioned in 1944, later the British cable ship MV Giant II and then the University of Hawaii research vessel MS Mahi before being sunk as a reef in 1982.
Sources
- The Mahi (Wreck) — Scubago — Scubago / SSI MyDiveGuide
- USS Scrimmage — Wikipedia — Wikipedia
- Oahu — Wikivoyage — Wikivoyage
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