Thunder Bay National Marine Sanctuary, Michigan

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Inside the cavernous stern hold of the wooden freighter Grecian (August 2018)
Chart Courtesy of NOAA
No trip to Lake Huron would be complete without enjoying the pristine dark skies; the Milky Way rising over the Lake

Thunder Bay is both a NOAA National Marine Sanctuary, and a Michigan State Underwater Preserve. For more information on the shipwrecks and the preserve, visit the official websites:

Michigan State Underwater Preserve, Thunder Bay

NOAA Thunder Bay National Marine Sanctuary

It is estimated that as many as 100 shipwrecks lie within the current boundaries of the preserve, earning the region the nickname "Shipwreck Alley." Already discovered shipwrecks date from 1849 through 1966, spanning more than a century of history. Michigan State underwater preserves are extremely user-friendly; most wrecks are buoyed for easy access, and divers are encouraged to explore these magificent time capsules of history.

The sterns of two ships lie 12.5 miles and 94 years apart on the bottom of Lake Huron, representing two drastically different eras in shipping history. The Pewabic, a wooden-hulled, twin-screw steamship sank in a collision on August 9, 1865 (above left). Standing upright in 165 feet of water, her hull has withstood two efforts to salvage the copper ingots that were her cargo. While the hull shows some damage, her stern is still a magnificent sight. Nearly 100 years later, the steel-hulled, single-screw freighter Monrovia was also lost to collision on June 25, 1959 (above right, w/ Mike Powell). Again the subject of salvage attempts that have left her hull somewhat twisted, she is largely intact and a fabulous dive; Karen Flynn exclaimed after diving her "this is like Truk Lagoon in cold water!" (both August 2018)

The Grecian (June 15, 1906)

The Grecian is surely one of the signature shipwrecks lying in Thunder Bay. Sitting upright in 105 feet of water, she is easily reached by recreational divers. Her stern half is in pristine condition--typical for many Great Lakes Shipwrecks. A huge cavernous cargo hold is wide open to exploration (top of page).

The Grecian's stern is remarkably intact and towers above the lakebed, while the forward end gives entrance to a section of her ample-sized cargo hold (both August 2018).
An open corridor leads aft from the cargo hold into her engine room (above left-to-right, swimming down corridor and into engine room, August 2018).
The inside of the Grecian's cargo hold is not only a huge network of beams and pillars punctuated by shafts of sunlight, but is a fascinating place to explore (above left, w/ Mike Powell). Among the debris is a wheelbarrow half-buried int he sandy bottom (above right, both August 2018).

Pewabic (August 9, 1865)

The Pewabic, a wooden-hulled, twin-screw steamship sank in a collision on August 9, 1865. Standing upright in 165 feet of water, her hull has withstood two efforts to salvage the copper ingots that were her cargo. When we visited her there was no buoy, but she proved a beautiful dive with fabulous visibility.

The Pewabic's hull is broken just aft of the bow (above left), giving the impression that she is taking a nose-dive into the lake bottom. Her stern, however, stands proud, with a well-preserved fantail girded by the elegantly curved remains of her deckhouse walls (above right, w/ Karen Flynn, and below, all August 2018).
Portions of the Pewabic's holds are accessible for exploration (above left), while the damage done by salvage attempts is evident toward the bow, where her hull is broken and the deck and upper structure is missing (above right, both August 2018).

Monrovia (June 25, 1959)

Wrecked in an entirely different era than the Grecian and Pewabic, the steel-hulled freighter Monrovia is reminiscent of Truk Lagoon, but in much, much colder water! Perhaps that makes sense, however, since the 432-foot long steel freighter was built in 1943. She sits upright in 140 feet of water outside the entrance of Thunder Bay, but still well within the preserve.

The Monrovia's fantail complete with railings (above left w/ Mike Powell) and open cargo holds invite exploration (above right, w/ Dave Etchison, both August 2018).
Swimming (or better yet, scootering!) the 432 foot length of the Monrovia allows visitors to view the wreck in her entirety, from the broken bow lying on its port side, to the upright bridge, and finally the towering stern with single propeller and rudder (all August 2018).

More Shipwrecks to Explore....

There are many more wrecks to explore in and around Thunder Bay. The Lucinda Van Valkenburg (May 31, 1887, above left w/ Mike Powell) has half her bow standing while the other half has collapsed; the E.B. Allen has both her bow and stern sections intact (above, middle, November 18, 1871); the Montana (above right with Mike Powell) was a wooden steam barge that burned and sank in 1914. She has a small but tall steam engine, unique boiler and propeller visible, and on our visit was above the thermocline! (all August 2018).

Links to dive operators and websites in the Great Lakes region:

Captain Brian Anderson's charter operation

Black Dog Diving Charters

Straits Scuba Center in St. Ignace, MI

Straits Scuba Center

NOAA's Thunder Bay website

Thunder Bay National Marine Sanctuary

Michigan Underwater Preserves website

Michigan Underwater Preserves

Special thanks to Backscatter, the Premier source for underwater photography and video equipment.

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