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Schooner of 1908 lying in 3-6.5 m in Keweenaw Bay east of the Portage entry. Broken hull on sand and rock, shallow enough to snorkel; open to the east, so pick a day with the wind off the land.
Google MapsToday — sit it out.
Sources & confidence
Compiled by the spearo sea-state engine · How it works →
The verdict comes from seven water factors and hard safety gates — not ten tabs. Go or stay.
Our own model
Our own forecast engine — not a third-party widget. It weighs these water factors into one go-or-stay verdict for this coast; the 0–10 dial is that verdict, read out as a number.
Safety gates
It all folds into a single 0–10 score and one verdict: go or stay.
A forecast, not a guarantee — the sea has the last word.
Where to get in, where to hunt
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The models set the window. Whether you go in is read only at the water: count the sets, watch the surge on the entry. If in doubt, you don't get in.
Scouted entries, coloured by today. The colour is the sea state at the spot, not a guarantee: the wash and a slippery entry you judge on site.
Open the seafloor mapSchooner of 1908 lying in 3-6.5 m in Keweenaw Bay east of the Portage entry. Broken hull on sand and rock, shallow enough to snorkel; open to the east, so pick a day with the wind off the land.
Google MapsThe half-sunk Quincy dredge in Torch Lake off Mason, with its superstructure standing clear of the water and the hull on the bottom in a few metres. A shore-view landmark and shallow snorkel; stamp-sand bottom, so silt out fast.
Cameras, map and reference — to hand as you come up.
Check the cam BEFORE you leave. Foam, brown/green murk, or waves washing the entry rocks = No-go. At night/in fog the cam is useless — treat it as «unknown», NOT «green».
Michigan Technological University
Michigan Technological UniversitySOLO is the biggest risk: underwater you can black out from lack of oxygen silently and fatally, with no one around. Solo is never truly «safe». Below are the best weather windows; carry a buoy, tell someone your plan and exit time, and any doubt — don't go.
US spearfishing law is state-by-state. License, spearable species, powerhead rules and distances vary; federal sanctuaries (Gray's Reef, the Keys, Flower Garden Banks) ban spearfishing. Always confirm with the state agency and local ordinances.
Houghton is the mainland gate to Isle Royale National Park — the Ranger III ferry and diver registration are at the Houghton Visitor Center — and the town itself sits on the sheltered Keweenaw Waterway, which holds the easiest shallow wrecks in Copper Country. Under the 2026 rules this is inside the Lake Superior underwater-spear water: the game fish are open, minus Stannard Rock, Big Reef, Isle Royale and Pictured Rocks National Lakeshore. Freedive only, daylight only, and a free underwater spearfishing licence on top of the fishing licence, with no monthly reporting since the 2026 season.
Depths below are the published site depths, not a promise about conditions. Outside the buoyed preserve sites you find the mark yourself.
| Spot | Type | Depth | Level | Access | Notes |
|---|---|---|---|---|---|
| Sailor Boy | Wreck | 5 m | Beginner | Boat, sheltered waterway | Small 1923 wreck a few minutes from the lift bridge, in sheltered, low-current water. The easiest checkout dive in Copper Country, though waterway visibility is modest. |
| Uarda | Wreck | 6 m | Beginner | Small boat, off the commercial channel | The 1912 Uarda in the Portage Lake ship canal west of Houghton. Protected water and a soft bottom around the hull; the site sits clear of the commercial channel. |
| America | Wreck | 0.6–24 m | Intermediate — no spearing (NPS) | Charter from Houghton; register with the park | Isle Royale's most dived wreck: the 1928 passenger steamer with her bow near the surface and stern at 24 m. Engine room, windlass and cabins are intact below 9 m. Inside the national park, so it is a dive, never a hunt. |
| Glenlyon | Wreck | 5–18 m | Beginner to intermediate — no spearing (NPS) | Charter from Houghton, NPS moorings | Bulk freighter wrecked on a shoal in 1924 and scattered at Isle Royale, with propeller, engine and boilers open to inspection. Shallow, bright, and a good first Isle Royale dive. |
Yes, within limits. Michigan's 2026 underwater-spear waters are named lake by lake: Lake Michigan from the MI/IN border to the 45th parallel, a 2-mile strip in Green Bay to the Ford River mouth, a 5-mile strip from Point Detour to the Brevort River, Lake Huron from the Thunder Bay River pier at Alpena south to Fort Gratiot Light, Lake Erie to the Celeron Island line, and Lake Superior to the St. Marys River — with Grand Traverse Bay, Stannard Rock, Big Reef and the 4.5-mile ring round Isle Royale cut out of them. The 2026 regulations opened Michigan's Lake Superior water — the MI/WI border east to the St. Marys River — so lake trout, northern pike and walleye are open here, with Stannard Rock, Big Reef and the 4.5-mile ring round Isle Royale cut out of it. What stays open is the year-round list, which runs in all Michigan waters except designated trout lakes and streams and the Michigan-Wisconsin boundary waters. The instrument is the Bow & Spear Fishing Regulations table of the Michigan Fishing Guide, a Fisheries Order under NREPA Part 487.
The year-round Michigan list is the backbone: bowfin, bullheads, burbot, common carp, catfish, cisco, freshwater drum, gizzard shad, goldfish, grass carp, longnose gar, rainbow smelt, suckers and lake whitefish. On these lakes whitefish, cisco and burbot are real targets on it, not a consolation prize. Lake sturgeon is off the table: spearing it is prohibited except in a special Black Lake winter season, and on every water here it is closed or release-only. Michigan's table is an enumerating one: trout and salmon other than lake trout, bass, sunfishes and crappie are not named, so they are not open.
Two licences, not one. You need the Michigan All Species fishing licence — 26 USD resident, 76 USD non-resident, 10 USD a day, from age 17 — plus a free annual underwater spearfishing licence, which is mandatory — though its monthly effort-and-harvest report was abolished for the 2026 season. The gear rules are just as concrete. A rubber- or spring-propelled spear may be fired only while you are fully submerged, and it must be tethered to a line no longer than 20 ft. Scuba and rebreathers are prohibited while underwater spearfishing, so this is a freedive discipline. Daylight only, bands unloaded whenever you move between areas, and 150 ft off swimming areas, docks, boat access sites and power intakes — which effectively closes harbour mouths.
Isle Royale is a national park, and fishing in any manner other than hook and line is prohibited in national parks — the Michigan DNR says so on its own bow and spear page. So the island wrecks are dives, never hunting marks, and divers register at the Houghton Visitor Center before they go. On the mainland side of the Keweenaw the ordinary Michigan rules apply again.
Bays and harbours freeze from January to March. The dive season runs from late May to October and peaks in August and September; the surface rarely passes 13-15 °C and below 15 m the water sits at 4-7 °C all year round. Plan for a thick suit with hood, gloves and boots, or a drysuit: the thermocline shapes every dive here, and what feels workable at the surface is a different lake ten metres down. There is no tide on the Great Lakes — the level moves with wind and pressure.
Cold is the first risk and it is not seasonal: below the thermocline the water stays a few degrees above freezing all summer, and the freedive-only rule leaves you no gas reserve to buy time with. The second is exposure. Most of these sites sit in open lake with no shelter and, outside the buoyed preserves, no mooring at all, so weather windows are short and a shot line is your own responsibility. Finally, ice: the water freezes for months, and frazil and shore ice make the shoulder seasons a different sport.
Yes. Under the 2026 rules this is inside the Lake Superior underwater-spear water: the game fish are open, minus Stannard Rock, Big Reef, Isle Royale and Pictured Rocks National Lakeshore. The year-round list stays open on top of them.
No. Scuba, rebreathers and similar devices are prohibited while underwater spearfishing: Michigan is freedive-only.
The Michigan All Species fishing licence plus a free annual underwater spearfishing licence, whose mandatory monthly effort-and-harvest report was abolished for the 2026 season.
No. It is prohibited from 30 minutes after sunset to 30 minutes before sunrise, and you must stay 150 ft off swimming areas, docks, ramps and power intakes.
No. Fishing in any manner other than hook and line is prohibited in national parks, so those wrecks are dives only. Hunt outside the federal boundary.
Bays and harbours freeze from January to March.