Connect with us


Lake Erie Technical Wreck Diving Guide: A Necessary Tool

Veteran wrecker and instructor Gene Petersen dives deep into Erik Petkovic’s second book on Lake Erie shipwrecks. This time Petkovic pushes far beyond the [recreational] limits venturing into deeper wrecks that lie on the lake’s bottom. Peterson calls the book a “necessary tool” for any deepwater diver getting ready to explore these shipwrecks.



by Gene Peterson

Header image of book cover courtesy of E. Petkovic

Erik Petkovic Sr.’s original book, Shipwrecks of Lake Erie, Volume One, is jam-packed with adventurous wreck diving history within recreational diving limits—no-stop dives to 40 m/130 ft. In his latest edition, Petkovic has gone beyond the limits and ventured to deeper wrecks in Lake Erie Technical Wreck Diving Guide. The historian takes this book to a new documentation level in this unique, comprehensive guide for technical deep wreck divers. The accuracy of the guide demonstrates the author’s drive to present a thrilling, non-fiction read with remarkable wreck survival tales, heroic accomplishments, and dramatic narratives. 

A rare drawing of the Straubenzee. Courtesy of Erik Petkovic

Petkovic demonstrates his passion for history by  thoroughly recounting nineteen ship’s careers and disasters. Rarely visited because of their depths, the author thoroughly examines the remains of the nearly untouched sites strewn across the floor of Lake Erie firsthand. Relics such as bells, helms, portholes, deadeyes, and related discoveries litter these hulks. They remain untouched in situ, preserved in the fresh lake water. These protected sites are threatened only by the weight of the zebra mussels that flourish in the dark, productive environment and whose increasing weight may lead the sites to collapse. Petkovic draws the reader in, describing his journeys to these sites and sharing the in-depth research that led him to explore these haunting wrecks. As a diver, his writing encourages me to go beyond the armchair and venture, as he did, to explore each wreck site firsthand. 

Each narrative unveils so much history. It is remarkable that these stories have been overlooked until this guide was printed; otherwise, these records may have been swept away. The writer preserves the fateful tales of those souls destined for tragedy on these historic voyages. Such is the story of the sinking of the sidewheel steamer Atlantic, which caused the greatest loss of life on Lake Erie to date. Over 300 passengers perished during the collision with the steamer Ogdensburg on August 20, 1852—nearly half the passengers. Of notable interest are the fearless salvage attempts and successes by hard hat divers in the early 1800s. Authorities offered a five thousand dollar reward to anyone who could retrieve the ship’s safe, leading these pioneers of deep diving to risk serious injury in order to pursue the reward.

Despite her depth of 50 m/165 ft, the Atlantic was clearly an alluring challenge for these men. Petrokvik’s telling of the bold attempt by diver John B. Green—who faced the depths of this cold and dark water multiple times—is compelling and memorable. Undaunted by the limited technology of the time, Green fearlessly hunted the treasure until decompression sickness struck. Ultimately, the safe was recovered by a competitor following Green’s trail of buoys in the limited visibility. The story is curiously familiar to modern-day pursuits. One must follow the author’s narratives throughout the book to admire his remarkable perceptions. I admire Petkovic’s principles, which are subtly presented, as well as his exploration of the balance between earned honor and purloined glory.

Side Scan Sonar of the Straubenzee. Photo courtesy of Garry Kozak

The deepest wreck in Lake Erie, the Straubenzee, had a prominent history of near disasters prior to her demise. Checkered by groundings, hit and runs, near collisions, actual collisions, and riotous boardings, the Straubenzee peppered newspaper columns throughout her career. A collision with the steamship City of Erie ended her notorious career, sending the barquentine to the depth of 61 m/200 ft on September 27, 1909. Her wreckage remained unseen until wreck hunter Garry Kozak discovered the broken hull in July of 1982. Petkovic describes the wreck as phenomenal and strewn with artifacts, even though the hull is separated by a 7.6 m/25 ft gap. Both sections are picturesque.     

Underwater photo of Sir CT Van Straubenzee courtesy of Tom Wilson.

The illustrations, news clippings, and fantastic photos by well-recognized photographers such as Becky Schott, Gary Gentile, Steve Gatto, Chris Kohl, Vlada Dekina, Tom Wilson, and Warren Lo draw the reader deeper into the writer’s unique descriptions. Each wreck is annotated with a sidebar describing the ship’s features and providing a brief history, an updated wreck account, and the degree of dive difficulty. 

Erik A. Petkovic’s Lake Erie Technical Wreck Diving Guide is a necessary tool for any deep water diver preparing to explore these Great Lakes shipwrecks, and it is a brilliant edition to any serious marine historian’s collection.  

An avid wreck diver, Gene has logged thousands of wreck dives off the Atlantic Coast from Florida to Newfoundland. These exciting adventures have included the discovery of more than 30 undived wrecks, eight Andrea Doria expeditions, and a position as acting diving safety officer for Gary Gentile’s 1990 U.S.S. Monitor Photographic Expedition. He led dozens of wreck hunting expeditions to Nova Scotia and numerous wreck discovery adventures off the Mid-Atlantic coast. Gene has an active 100-ton Ocean Operator’s license and a teaching degree from Rowan University. Gene has received honors from the New Jersey Council of Dive Clubs and from the National Association of Underwater instructors for his 45 years of dedication to safe diver training.






Text by Andrea Marassich. Photos courtesy of Phreatic. Header image: An inflatable (aka The love boat) is used to facilitate transportation of diving gear through the lakes.

Locoli cave is an amazing and challenging spring in the wilderness of Montalbo, Sardinia. It took me three years to set up the project, but it was all worth it. After all, David Rhea taught me that, “Slow is smooth, smooth is fast.”

I’m Andrea Marassich. I began exploring underwater caves in 2003, and I have taken part in cave exploration missions all around the world. In 2010, I fell in love with the powerful, majestic cave systems of Northern Sardinia, Italy. As a result, in 2014, I founded a nonprofit association, Phreatic, which collaborates with scientists and researchers in geology, paleontology, and earth sciences to study and document these unique environments. 

In 2019, I presented at Icnussa, the international speleology meeting in Sardinia, and spoke about Phreatic projects. During the event, a local caving club offered to carry diving gear to the first sump of a cave I had never heard of: Sa Conca ‘e Locoli. I dove with fellow GUE instructor Stefano Gualtieri, and  it was love at first sight. During the dive, I realized that I wanted to get back for more survey and exploration.

The Environment

“Locoli” is a temporary spring (active after rainfall and during certain seasons) located into Montalbo limestone massif, and is included in the UNESCO MaB (Man and the Biosphere) reserve of Tepilora, Rio Posada e Montalbo. 

Unesco Mab Tepilora Park: Karst, wetlands and coastline.

This Sardinian version of the Dolomites Alps, with its white rocks, looks out onto 25 km/16 miles of coastline. The silver ridge of Montalbo features evocative itineraries: historic trails for coal merchants and shepherds, archaeological sites, holm oak forests, and Mediterranean scrub (populated with mouflon, the golden eagle, and the red-billed chough). The peak presents doline valleys, chasms, underground rivers, as well as caves prehistorically inhabited by the Nuragic civilization. Archaeologists uncovered iron weapons in Bona Fraule, Gane ‘e Gortoe is rich in limestone concretions, Sa Conca ‘e Locoli  is eroded by the fierceness of the water, and Sa Prejone ‘e ‘Orcu is a cave-sanctuary.

Sa Conca’e Locoli

Locoli spring, which can submerge the whole valley during winter flooding, forms the entrance to the massive cave system hidden beneath Montalbo. The entrance cavern leads to a series of crystal-clear, freshwater lakes, and though the access is not technically complex, it requires the use of ropes through multiple changes of elevation, while the decorations and speleothems inside alternate with the smooth rocks levigated by water passage. 

Rope work and SRT is required to reach sump1. Hauling gear and physical effort is a serious part of the game.

After the lakes, the cave splits in two. The south passage leads to a shallow sump looping back downstream and connecting to a minor spring in the valley. The north passage goes through a series of changes in elevation, which require the use of ropes, and leads to a wide passage that provides access to the surface of Sump 1. 

This is the entrance gate to a series of huge flooded passages of breathtaking dimensions with obvious signs of a huge aquifer. The first sump is not particularly long or deep at 250 m/820 ft long with a maximum depth of 23 m/76 ft, but it leads to a very important second split. Here the subterranean river flows downstream toward the village of Siniscola and the Fruncu ‘e Oche spring, while on the upstream side it heads toward four other challenging sumps and dry areas. 

In the island of Sardinia, Sump 3 is the deepest, reaching 90 m/295 ft. 

The last exploration dive carried out in 2009 by Rick Stanton led to a collapse in Sump 5; consequently, the present survey only covers the first two sumps.  

The Project

In 2020, I organized the first scouting mission of the deeper sumps, together with Jan Medenwaldt. COVID-19 travel limitations presented difficulties in gathering a bigger team. 

In 2021, finally, we managed to organize a three-week campaign encompassing both survey and photogrammetry. The exploration of the system is particularly complex for a variety of reasons. First, the underwater portion is accessible after a relatively long dry passage, one in which cavers and cave divers must carry all their heavy gear. Subsequently, the series of sumps is difficult from a technical point of view, as the diving profiles involve serious exposures in Sump 3 and 5. 

After the dives were completed, the long clean up requires a couple days, but the smile don’t lie. Operations went smooth.

In order to complete the working goals connected with survey, mapping, photo/video, and research tasks, divers needed to extend their diving time and elected to stay inside the cave and set up a bivouac; entering the cave with dry tubes and bivouac gear without knowing where to establish the camp was risky. We found a new dry section between Sump 3 and 4, which proved to be ideal to bivouac and minimize the decompression risks connected with the profile. 

The main challenge is dealing with the geology of the cave, one that presents multiple elevation changes to move from one sump to the next. Sump 3 is the most demanding of the five underwater galleries, as the cave drops initially to 45 m/148 ft deep, then rises to 15 m/49 ft, drops to 90 m/295 ft, ascends again to 45 m/148 ft, and drops again to 65 m/213 ft before the final ascent. 

We deeply believe exploration without documentation is not getting the job done. Survey and documenting with media is a key component of our activities and we prioritize it over simply “reaching a distance”.

The exploration efforts are now divided in two areas: the newly discovered dry section between Sump 3 and Sump 4, featuring massive rooms and high chimneys that potentially connect with a fossil gallery above, and Sump 5, whose exploration stopped at a depth of 50 m/164 ft and needs  further investigation.

We are already working on new project sessions for summer 2022. 

Considering the importance of the karst system of Montalbo and its water reservoirs, the UNESCO MaB reserve decided to support our project, specifically in relation to our documentation and conservation efforts. We also received the sponsorship of the Italian Speleological Society and are now searching for more partners. 

The main objectives will be:

  • Completing the survey of the upstream section up to Sump 5. To perform this task, we will use the SUEX DRIVe and mapping devices combined with MNemo.
  • Creating a documentary featuring the most beautiful passages of the cave with the help of an expert photogrammeter and videographer.
  • Improving public awareness about caves and karst in partnership with the International Year of Karst and Cave initiative provided by the International Union of Speleology.

Citizen Science

Phreatic believes in the power of Citizen Science. All our projects and missions rely upon the crucial involvement of skilled, specially trained individuals. The Sa Conca ‘e Locoli cave project involves a number of local and foreign volunteers with various sets of competences. Many thanks to Speleo Club Nuorese for the support in the dry portions of the cave, and to all the Phreatic volunteers who joined us in 2021 including Jan Medenwaldt, Peter Brandt, Sven Bertelmann, Keith Kreitner, Laura Marroni, Elke Riedl, and Irene Homberger. 

Entrance of one of the multiple downstream passages; While one team was diving the upstream sumps and bivouacked in the further section, operations continued with oc team working in a different area.

Collaborations and Partnerships

Phreatic can count on a long-term partnership with SUEX, a world leader in high-performance underwater vehicles designed for long-range technical and professional diving.

The Locoli project operates under the supervision of the geologist Dr. Francesco Murgia, author of multiple scientific publications on the areas of Montalbo and Supramonte.

For more information see: Phreatic: Citizen Science and Groundwater Research. Email contact:

Continue Reading

Thank You to Our Sponsors


Education, Conservation, and Exploration articles for the diving obsessed. Subscribe to our monthly blog and get our latest stories and content delivered to your inbox every Thursday.

Latest Features