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.

Lead Image

(No suitable public-domain image could be located online specifically for this wreck. The representative image you provided remains the best visual available.)

Shotline Diving Wreck Profile

• All information is drawn from 3DShipwrecks.org site data (3DShipwrecks.org).
• Preserve context is supported by Michigan Department and Wikipedia data (Wikipedia).

Description

The wreck features a main deck and intact hull; however, the fantail is broken and detached. Machinery includes a haystack-style boiler, feedwater pre‑heater, and a single-expansion engine closely matching those on the 19th-century propeller steamer Indiana (now part of the Smithsonian collection). The propeller is missing—and the aft deck structure appears disarticulated, with propeller-shaft hanger-bearing rods visible. On-site artifacts include an anchor windlass with rocker arm (likely operated from forecastle or spar deck), anchors lying on deck, mast remnants, capstan, bits, and two hand-operated cargo winches on the port side, along with scattered hand carts. The sides of the hull lie adjacent to the main hull on the lakebed (3DShipwrecks.org).

History

• Operational Profile & Machinery Origin: Based on engine and boiler design, this vessel likely dates from the mid-1800s. The machinery’s similarity to that of Indiana strengthens this estimate (3DShipwrecks.org, glsps.clubexpress.com).
• Ownership Chain & Registry: Not yet identified; no registry or official number currently associated with the wreck (3DShipwrecks.org).
• Final Voyage & Incident: Insufficient data exists to reconstruct the final voyage or cause of loss. The missing propeller may hint at salvage activity, but this remains speculative without confirmation (3DShipwrecks.org).

Final Disposition

• Cause of Loss: Undetermined—mid‑19th-century steamship loss suspected, but no documented cause.
• Wreck Condition: Largely intact—but with broken fantail, missing propeller, and scattered structural debris including displaced sides.

Located By & Date Found

• Discovery: Documented on 3DShipwrecks.org, discovered via underwater remote modeling by Andrew Goodman’s team in July 2022 using a DPV-mounted camera (1,863 still shots, 30-minute dive) (3DShipwrecks.org).
• Located By & Method: Andrew Goodman (photographer) and modeler Ken Merryman (model completed August 2022). The dive was remote-photogrammetric, using DPV-mounted imaging equipment.

Notmars & Advisories

• Protection Status: The wreck lies within Michigan’s Thumb Area Bottomland Preserve, where disturbance or removal of artifacts is strictly prohibited under state law (3DShipwrecks.org, Wikipedia).
• Hazards: None officially noted beyond general diving concerns.

Dive Information

• Access Type: Likely Boat—typical for Thumb Area wrecks (shore access is limited) (glsps.clubexpress.com, Scuba Diving).
• Entry Point: From nearest marina or launch at Port Austin or Harbor Beach.
• Conditions: Visibility can vary, often modest; Lake Huron’s clarity is seasonal. Depth is unspecified but likely beyond recreational limits without a known site depth. Diving may require technical certification, given typical regional depth profiles (many wrecks beyond 100 ft / 30 m) (Scuba Diving).
• Depth Range: Unknown—further survey required.
• Emergency Contacts & Permits: Use local NOAA rescue or Michigan DNR dive guidelines. No permits are generally issued—wreck is protected, so only non-intrusive documentation allowed.
• Local Dive Support: Charter services available via Port Austin or Alpena dive operations (Manistee News Advocate).

Crew & Casualty Memorials

• Crew List & Fate: Names remain unknown due to unidentified vessel.
• Memorial Records: None found—no registry, casualty list, or obituary records available. Further archival research (e.g., maritime newspapers, vessel registries) would be needed.

Documented Statements & Extracts

“The machinery includes a haystack boiler, feedwater pre‑heater and single expansion steam engine of identical design to those on the propeller Indiana…” (3DShipwrecks.org)

Registry, Enrollment & Insurance Trails

• Official Numbers / Registry: Not documented. Likely not yet tied to known registry records.
• Suggested Next Steps: Search 19th-century U.S. and Canadian registry listings, insurance ledgers, and regional newspapers around Lake Huron for similar vessel descriptions.

Site Documentation & Imaging

• 3D Photogrammetry: Site documented via 30-minute DPV photogrammetric dive capturing 1,863 high-resolution still images (July 2022). 3D model completed August 2022 by Ken Merryman (3DShipwrecks.org).
• NOAA VR or 3D Modeling: None reported.

Image Gallery

(None available beyond the original representative image.)

Resources & Links

• 3DShipwrecks – Unidentified Thumb Wreck (site data & details) (3DShipwrecks.org)
• Michigan Underwater Preserves – Thumb Area Bottomland Preserve (Wikipedia)
• Michigan Underwater Preserves overview (legal protection) (Wikipedia)
• Regional diving context & other wrecks (michigandiver.com)

References

• 3DShipwrecks.org – Unidentified Thumb Wreck: technical site description, dimensions, machinery, model data (photography and modeling) (3DShipwrecks.org)
• Michigan’s Thumb Bottomland Preserve – site context and known wreck environment (michigandiver.com)
• Michigan Underwater Preserves (Thumb region) – legal protection, dive access, and hazard context (Michigan.gov)
• Diving regionally – conditions and depth context (e.g. Pennsylvania’s Dunderburg, Troy, etc.) (Huron Daily Tribune)
• Remote imaging and photogrammetry details – discovery reporting (GLSPS update) (glsps.clubexpress.com)

NOAA/WHS Shipwreck Record Card

Summary Notes

• The Unidentified Thumb Wreck offers a rare, well-preserved mid-19th-century steam-era vessel structure with intact machinery and hull features.
• It remains officially unidentified; further archival research (registries, insurance records, newspapers) may eventually reveal its identity.
• The site is responsibly documented using modern underwater photogrammetry and lies within a protected preserve ensuring its long‑term preservation.

Let me know if you’d like further archival deep dives (e.g., registry comparisons, mid‑19th‑century vessel lists operating in the Thunder Bay to Port Austin corridor) or assistance refining access/dive protocols for this site.