Unknown 16 – Dipper Dredge

Explore the remains of Unknown 16, a mechanical excavator barge scuttled in Lake Superior’s Thunder Bay, showcasing early 20th-century dredging technology.

Shotline Diving Wreck Profile

  • Name: Unknown 16
  • Type: Dipper dredge (mechanical excavator barge)
  • Year Built:
  • Builder: Unknown — no registry, no visible marking or builder plaque
  • Dimensions: Approx. 53.5 ft × 20 ft
  • Registered Tonnage:
  • Depth at Wreck Site: 10 m / 33 ft
  • Location: Thunder Bay “ship graveyard”, off Mission Island

Wreck Location Map

Vessel Type

Dipper dredge (mechanical excavator barge)

Description

The Unknown 16 is a wooden dipper dredge, approximately 53.5 feet long and 20 feet wide. The hull is upright and partially embedded in sediment, with the lower hull framing and flat bottom remaining intact. However, the deck machinery and superstructure have been removed or decayed. Likely remnants of dipper crane foundations are visible, and the framing appears reinforced for heavy loads.

History

The construction date of Unknown 16 is not determined, and it is believed to have been deliberately scuttled following abandonment or obsolete disposal of harbor maintenance vessels. Its presence in the Thunder Bay scuttled fleet highlights the evolution of harbor engineering and vessel disposal practices.

Significant Incidents

  • Deliberately scuttled following abandonment or obsolete disposal of harbor maintenance vessels.

Final Disposition

Unknown 16 is confirmed as a wreck, located in the Thunder Bay “ship graveyard” off Mission Island in Lake Superior.

Current Condition & Accessibility

The wreck is estimated to be at a depth of 10-18 meters (33-60 feet), consistent with other vessels in the scuttled fleet. The hull remains upright and partially embedded in sediment, with significant structural elements intact.

Resources & Links

[shotline_reference_links slug=”unknown-16-dipper-dredge” title=”References & Links”]

Unknown 16 represents a rare surviving example of industrial dredging technology from the Great Lakes region’s maritime infrastructure heritage. Investigating its build and origins can enrich understanding of pre-steel dredge design and early 20th-century harbor modernization.

Legacy Notes & Full Historical Record

This section preserves the original unedited Shotline content for this wreck so that no historical detail is lost as we transition to the new logbook format.

Site Identification

  • Derelict ID: Unknown 16
  • Vessel Type: Dipper dredge (mechanical excavator barge)
  • Construction Date: Not determined (n.d.)
  • Material: Wood
  • Dimensions: Approx. 53.5 ft × 20 ft
  • Builder/Origin: Unknown — no registry, no visible marking or builder plaque

Wreck Site & Disposition

  • Location: Thunder Bay “ship graveyard”, off Mission Island, Lake Superior
  • Depth: Estimated 10–18 m (33–60 ft) — consistent with other vessels in the scuttled fleet
  • Disposition: Deliberately scuttled following abandonment or obsolete disposal of harbor maintenance vessels

Structural Description & Condition

  • The hull is upright and partially embedded in sediment
  • Lower hull framing and flat bottom remain intact; deck machinery and superstructure have been removed or decayed
  • Likely remnants of dipper crane foundations visible; framing appears reinforced for heavy loads

Research Potential & Next Steps

ObjectiveProposed Action
3D DocumentationCarry out photogrammetry surveys to record hull dimensions and dipping mechanisms
Timber Sampling & DatingExtract core samples for dendrochronological dating and identification of wood species
Archival ResearchCheck regional Douglas County and Port Arthur drilling logs for launch and procurement details
Hardware ExaminationExamine bolts and fittings for maker’s marks or date stamps
Comparative AnalysisCross-reference with known dredge plans and dimensions from early 20th-century dredge fleets

Significance

Unknown 16 represents a rare surviving example of industrial dredging technology from the Great Lakes region’s maritime infrastructure heritage. Its presence in the Thunder Bay scuttled fleet underscores the evolution of harbor engineering and vessel disposal practices. Investigating her build and origins can enrich understanding of pre-steel dredge design and early 20th-century harbor modernization.

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