NBM Dive Site Resource
Algoma (McMullen & Pitz Dredge)
Cleveland, Wisconsin, United States
Historic dredge wreck near Sheboygan at advanced recreational depth.
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Aquatic life at this dive site
What divers may encounter
Three reviewed connections are featured here. Sightings vary by season, conditions, and chance, so they are never guaranteed.
Quagga Mussel
Dreissena rostriformis bugensisNOAA reports quagga mussels as the dominant dreissenid in Lake Michigan and documents invasive mussels colonizing shipwrecks well beyond Algoma's 85-foot depth.
Motte123Open Aquatic Life Profile →
Round Goby
Neogobius melanostomusNOAA identifies round goby among fishes associated with the sanctuary's rocky bottom habitat and notes that wreck structures provide shelter and foraging habitat.
Peter van der SluijsOpen Aquatic Life Profile →
Lake Trout
Salvelinus namaycushNOAA identifies native lake trout in the sanctuary and explains that shipwrecks provide foraging habitat for predatory fish. A passing trout is possible, not guaranteed.
Knepp Timothy, U.S. Fish and Wildlife ServiceOpen Aquatic Life Profile →
Site media
Photographs
Three views rotate from the published gallery on each visit.
Contributor media
Dive videos
Three featured video positions are reserved on every profile.Recent field observations
Diver-reported temperatures
Automatically checked observations from dives during the past 14 days. Three reports are visible at a time; scroll for more.A report that passes the automatic checks will appear here with the dive date, diver’s display name, and temperatures at each depth.
Reports are automatically checked for plausible dates, depths, and temperatures. They are observations, not forecasts; confirm conditions before diving.
Seasonal planning reference
Typical monthly conditions
Long-term averages, not a forecast. Actual air and water conditions can change quickly and may vary across the site.Moderate-confidence match — Matched by documented Great Lakes port/area. Air and surface-water values are regional planning averages. No bottom-water line is published because a comparable depth-specific record has not yet been verified.
| Month | Average air | Surface water | Bottom water | Bottom measurement depth |
|---|---|---|---|---|
| Jan | 24.0°F / -4.4°C | 35.2°F / 1.8°C | No reliable record | — |
| Feb | 27.1°F / -2.7°C | 36.6°F / 2.6°C | No reliable record | — |
| Mar | 36.4°F / 2.4°C | 37.8°F / 3.2°C | No reliable record | — |
| Apr | 46.3°F / 7.9°C | 38.3°F / 3.5°C | No reliable record | — |
| May | 57.1°F / 13.9°C | 42.5°F / 5.8°C | No reliable record | — |
| Jun | 67.6°F / 19.8°C | 53.7°F / 12.1°C | No reliable record | — |
| Jul | 73.3°F / 22.9°C | 68.2°F / 20.1°C | No reliable record | — |
| Aug | 72.3°F / 22.4°C | 72.2°F / 22.3°C | No reliable record | — |
| Sep | 65.0°F / 18.3°C | 68.4°F / 20.2°C | No reliable record | — |
| Oct | 53.0°F / 11.7°C | 58.5°F / 14.7°C | No reliable record | — |
| Nov | 40.4°F / 4.7°C | 49.0°F / 9.4°C | No reliable record | — |
| Dec | 29.5°F / -1.4°C | 43.7°F / 6.5°C | No reliable record | — |
Wisconsin State Climatology Office — Milwaukee Climate Data
1991–2020 climate normalsReview source ↗NOAA NCEI Coastal Water Temperature Guide — Station 45007
Historical monthly station averagesReview source ↗Bottom temperature is never inferred from surface temperature. A blank month means no reliable depth-specific average is available. Data reviewed 2026-08-26.
Why divers know this place
Highlights
Industrial dredging machinery and working-vessel history.
Shipwreck-only module
The wreck
This section appears only on shipwreck records and brings the vessel, its loss, present condition, access, and responsible wreck-diving considerations into one place.
- Vessel type
- Wooden steam-powered dredge
- Year built
- 1918
- Year sunk
- 1919
- Vessel length
- 79.6 ft
- Cause of loss
- Storm while under tow, November 18, 1919
- Wreck orientation
- Upright
- Present condition
- Mostly intact dredge with crane boom, boiler, gears and cleats.
- Penetration guidance
- Interior spaces are overhead environments. Entry requires appropriate wreck training, equipment and a planned exit; depth alone does not establish suitability.
History and significance
Owned by McMullen & Pitz, Algoma was under tow by Arctic with two dump scows when heavy seas overwhelmed it off Cleveland, Wisconsin. Five crew members escaped to the tug before the dredge was cut free. Its machinery preserves the history of sand-and-gravel extraction.
Plan the trip
Dive boats that visit this wreck
Regional context
Located within
Before you arrive
Access notes
Boat-access sanctuary site; verify current mooring and charter availability.
Plan within your training
Conditions and hazards
Cold water, variable visibility, machinery entanglement, sharp metal and overhead spaces.
Independent resource notice
This record is a starting point for independent verification. Access, closures, moorings, weather, currents, depth, visibility, operator availability, and site conditions can change without notice. Confirm current information with the responsible operator, property owner, managing authority, or another qualified local source before planning or attempting a dive.