Boat dive — see Entry & access.
SS Onoko Wreck is a expert boat dive site in Minnesota, United States with depths of 55–67 m (180–220 ft). Typically most favorable Jul · from 3 years of archive data. Divers commonly see Burbot. Check the latest conditions and entry details before you go.
Tap a factor for its source and model point
Site hazards: Extreme depth (~220 ft) · Very cold water (~2-4 C) at depth · Inverted, broken hull
All 6 hazards ↓Dive windows this week
Best: ThuFavorable windowModerate window— no window
First light 5:04 · Sunrise 5:40 · Sunset 20:47
Source: Open-Meteo wind · graded 3h ago
Forecast only — always assess conditions on site.
Forecast · NOAA tide model
Loading tide predictions
Dated firsthand observations from divers — not current conditions.
No diver reports for this site yet. — one dated observation helps every diver after you.
Based on community reviews and site data. Conditions vary — always verify before diving.
What conditions have historically been typical at this site, month by month — not a forecast.
July hastypically had the largest share of favorable days here. Conditions vary year to year — this is historical context, not a forecast.
Based on 3 years of archive data. Bar height shows the share of days each month whose conditions have historically scored favorably.
Species noted at this site — not a promise of what you’ll encounter.
No dive shops mapped within 25 km. Know one? Add it to the map.
The Onoko, launched in 1882, was the first iron-hulled bulk freighter on the Great Lakes and a direct ancestor of the modern laker. She sprang a leak and sank in 35 minutes on September 14, 1915, about 13.5 nautical miles east of Duluth, and was found in 1988 lying upside down and broken nearly in half in roughly 220 feet of water. It is a serious trimix-level technical dive: dark, silty, very cold and far offshore, visited only by experienced technical teams.
Extreme depth (~220 ft) — trimix/CCR technical dive only
Very cold water (~2-4 C) at depth
Low visibility and heavy silt over the mud bottom
Inverted, broken hull — disorientation and entanglement risk
Open-lake location 13.5 nm east of Duluth, weather-dependent
Mandatory staged decompression
SS Onoko Wreck is rated as expert difficulty, which may not suit new divers. A Full trimix technical certification (or equivalent CCR rating) certification or equivalent is suggested. Consider your experience level, conditions, and local guidance before planning.
SS Onoko Wreck has a depth range of 55–67 metres (180–220 feet). Check the dive site page for current conditions and any depth-specific guidance before planning your dive.
The best time to dive SS Onoko Wreck is typically Mid-summer to early fall on flat-calm forecasts.. Conditions vary, so check the latest reports and forecasts on the dive site page before your trip.
Divers at SS Onoko Wreck in United States commonly report sightings of Burbot. Marine life varies by season and conditions—check the site page for recent diver observations and photos.
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