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Lake Ontario - Zerwas Houseboat Wreck

Found by:  Dan Scoville & Chris Koberstein - Summer 2012

Location:  Off Oswego, NY

A Small Target
In the summer of 2012 Dan Scoville and Chris Koberstein were searching the bottom of Lake Ontario off Oswego, NY with a side scan sonar.  After many hours of fruitless searching a very small target scrolled down the sonar screen.  Quick measurements of this target showed it to be approximately 30ft long but little more information could be learned from the image.  Dan noted the position and Chris kept the boat on a straight course.  This target was certainly not what they were looking for but any image on the sonar screen helped break the monotony of a long search day.

A few days later Dan and Chris had compiled a short list of these small nondescript targets and decided to take a closer look at a few of them.  Chris piloted the boat back to the location of the first small target.  The remotely operated vehicle (ROV) was readied on the back deck and dropped over the side for a long descent to the bottom of the lake.

The sector scanning sonar illuminated a hard target a short distance from where the ROV landed.  Dan pushed the joystick forward and the ROV made a slow approach.  As the ROV closed in on the target its lights reflected off the wreck, outlining a familiar shape.  They had found a 1960s era houseboat covered with a thick coat of quagga mussels.  Chris and Dan were both surprised to find  a houseboat that  far out in the lake as houseboats  are not known for their sea faring  abilities.

After a surveying the wreck, the pair noted that it was in very good condition barring the smashed front window in the pilot house.  Flying the ROV around the boat Dan looked for any clues that might  explain how the boat came to be on the bottom of Lake Ontario or to whom the boat had belonged.  Along the port side a small bit of black could be seen under the pilot house window.  Dan flew the ROV over to the boat until the ROV’s grabber touched the boat’s port side.  Then, while slowly thrusting down, the ROV dragged the grabber along the side of the wreck scraping off some of the mussels as it went.  After a few passes they could see  the boat’s registration number was still intact under the thick layer of mussels.  Dan continued to scrape the side of the wreck until  “FL 7632 AR” was visible.   Moving slightly further aft the ROV also uncovered the registration sticker that read “Expires 6/30/72” and had the Florida state outline on it.  Dan and Chris wondered how a 1960s Florida houseboat ended up on the bottom of Lake Ontario.

Identifying the FL 7632 AR
With the Florida registration number in hand Dan assumed that finding the house boat’s history was going to be easy but that was not the case.  After many failed attempts to look up the registration number via Coast Guard and State of Florida archives, Dan finally gave up and started searching early 1970s newspapers for anything related to a sunken houseboat.  Following weeks of searching, an article was found that mentioned a houseboat had disappeared somewhere between Cape Vincent and Oswego, NY.  The captain of that boat was Preston Zerwas.   According to the newspaper article the boat Preston was piloting was 32ft long, white in color, and had a blue stripe.

FL 7632 AR measured 32 ft long on the ROV’s sector scanning sonar, it was white and after a careful look at the video, a blue stripe was found under the thick layer of mussels.   One item of concern was FL 7632 AR’s 6/30/1972 registration sticker.  The registration expired more than a year prior to when Preston made his fateful September 1973 trip.  A lingering question remained that could not be so easily dismissed, in all the articles they found about the search for Preston’s boat there was no mention of a Florida registration.  This question would have to be answered before positive identification of the boat could be made.

The Last Day

September 14th 1973 was Bob Lashomb’s last day at the George W Mercier shipyard in Clayton NY.  Bob was a long time employee at the shipyard and during his tenure he had held many positions throughout the marina.  Most recently he worked as a salesman and he went about his last day tending to customers with his usual easy manner.  Having recently purchased a local marina Bob was looking forward to starting a new adventure as the owner and operator of a houseboat rental business.  However, before he could head off he had one more boat to deliver for the George W Mercer shipyard.  The shipyard had recently sold a houseboat to  Miles Perkins who wanted to take delivery 70 miles away in Oswego NY.  Bob had to run the boat up the St. Lawrence River and across Lake Ontario to make the delivery.  Upon arrival in Oswego he would pick up another boat that had been traded in and make the  journey back across the open lake to Clayton.  On the up bound trip Bob would deliver the  32ft late 1960s era SeaRover houseboat that had recently been repaired at the shipyard.  This was routine work for Bob and as an experienced lake man it did not cause him any concern.

As midday approached, the president of the shipyard, Preston Zerwas, discussed the delivery with Bob.  As the conversation concluded  Preston agreed to make the run across the lake.  Preston had taken over managing the shipyard 3 years earlier shortly after the death of his Uncle Gene Springman.  Gene had managed the shipyard until he died suddenly in a car accident.  Sadly, he would not be the last president at the shipyard to meet an untimely end.

Around 4pm on September 14, 1973,  Preston boarded the SeaRover and threw off the lines.  Pulling off the shipyard docks he turned the boat south west and headed into the St. Lawrence River.  Around 6pm Preston arrived at Cape Vincent, NY.  This was  his last chance to get supplies or fuel before entering the open lake.  Preston pulled in at a marina where he filled both of the  45 gallon fuel tanks on the boat and purchased charts of Oswego harbor.  Starting this late in the evening Preston would arrive in Oswego well after dark and would need the charts to make safe entry into the unfamiliar port. 

The gas dock was being manned by Lance Balcom.  After learning that Preston planned to make the lake crossing that evening, Lance tried to persuade him not to go.  Preston decided to continue on. .  He had one boat to deliver, another to pick up, and he did not want to keep his client waiting.  Preston was an experienced boatman, having served four years in the US Navy and having worked at Mercier Marina every summer during his high school and college years. He would press on intending to make Oswego sometime during the night and then immediately return with the trade-in boat.  At that time the weather for the evening was fair, but, September is a temperamental month on the Great Lakes.  Many sailors have been caught off guard during this deceivingly tranquil time of the year only to find that the Lake Ontario can be a hard mistress.

After leaving Cape Vincent, Preston settled in for the 4 to 5 hour journey to Oswego.  Based on evidence found while searching the shipwreck with the ROV, it is probable Preston had been flying a kite from the boat when it sank.  As can be seen on the video, a spool of string lies on bow with the string paid out over the railing, then over the top of the houseboat.  When the ROV was retrieved to the surface, the kite string was entangled in the ROV propeller and the kite was retrieved from the end of the string. One can imagine that under a seat cushion or other houseboat nook, Preston found a child’s kite that had been missed during the boat’s pre sale cleaning.  Along the way Preston presumably walked out on deck with the kite, held it into the wind created by the forward movement of the houseboat, let it go and paid out the string.  Walking to the bow he tied the kite string to the front railing and continued on his way across the lake.  No doubt enjoying the fresh air and sunset as he rounded Galloo Island and changed course for Oswego some 40 miles distant.

The next day Miles Perkins waited patiently in Oswego for Preston to arrive but he was nowhere to be found, so he called Clayton.  Back at the Mercier shipyard Bob Lashomb called the Coast Guard to report Preston overdue..  The Coast Guard and many private parties launched an  extensive seven day air, land and water search for Preston and the houseboat,but, no trace of either was ever found.

The Florida Connection

Having exhausted the newspaper searches and still not made any connection between Preston’s boat and Florida, Dan turned to his friend Khris Hunt, a long time Clayton, NY resident and commercial diver.  According to Khris, the Zerwas name was well known in the small town of Clayton. He was sure that that someone would remember something.  Khris forwarded the information to Dennis McCarthy, a Cape Vincent resident with ties to the Thousand Islands Museum and a passion for shipwrecks.  With Dennis’s help the story began to unravel.  The first big break was a phone call with Bob Lashomb.  Bob remembered many details about the day Preston went missing, but the most critical detail, the Florida connection, still eluded Dan and Chris.

The US Coast Guard made a 7 day search for Preston starting the day after his disappearance.  Both Dennis and Dan assumed that the registration number for Preston’s boat would be contained in this report.   Dennis began his search for the report with his Coast Guard friends Sean Sulski and Gary Kicher.  Dan called the Coast Guard directly but had little success.  The Coast Guard responded that Dan or Dennis could apply for the information using the Freedom of Information Act, but they would likely no longer have the information in their files.

While searching the internet for “Preston Zerwas,” Dan found an obituary for Celesta Mae Jun, Preston’s mother¬-in-law.  This article listed all of Celesta’s surviving relatives, one of which was Minerva Zerwas Stalker, Preston’s wife.  Dan typed Minerva’s name into a search engine and came up with a phone number in Illinois.  After thinking about it for a couple days Dan dialed the numbers, the phone rang and Minerva (Minnie) picked up the line.  Dan explained that there was a chance that Preston’s boat might have been located but the last piece of the puzzle, the Florida registration connection, still needed to be confirmed.  Minnie asked if Dan  had read the Coast Guard report and he reported that he had been unable to locate a copy of the report.  Minnie thought that somewhere, packed away for 40 years, she still may have it.  Dan gave her his contact information and Minnie promised to call if she found the old document.

A week went by with no word from Minnie and not much forward progress.  Dennis and Dan continued their efforts to find the Coast Guard report through other means.  Then, on April 16th, the phone rang and the man on the phone introduced himself as Philip  Zerwas, Preston’s oldest son.  Philip thought that he might have the Coast Guard report packed away in a box and promised to take a look for it when he finished work that day. That evening Philip’s girlfriend Angela found the Coast Guard report in a box that had not been opened for many years.

Philip and Angela divided the report in half and each searched through their portion of the inch thick report, line by line, for the elusive  Florida registration number. Angela finished her portion first, with no evidence of the boat registration.  With only a few pages of the report unread, Philip was becoming anxious that his half of the report would not contain the missing registration numbers.  If this was the case, the family would continue living with the mystery of Preston’s disappearance. 

With only a few pages of the report remaining, Philip turned a page and the registration numbers seamed to leap off the page!   FL 7632 AR.  Preston’s boat had finally been found!  A family’s 40 year mystery was solved by Dan and Chris!

The Discovery Team​
Dan Scoville is an experienced cave and technical diver. In 2005, Dan led the development of an underwater remote operated vehicle (ROV) with a team of college seniors from the Rochester Institute of Technology. He is currently a project manager and electrical engineer for Oceaneering International in Houston, TX



Chris Koberstein is an experienced cave, technical and rebreather diver. Chris uses sophisticated rebreather diving equipment to explore depths to over 300 feet. Chris works as an aviation maintenance technician with Air Canada.

Contact information​
Dan Scoville - cell 1-832-423-6318

Chris Koberstein – home 1-450-458-3590 cell 1-514-236-0824

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