Rough Ride, Great Dive

 A group from Liquid Archaeology was invited by SOS Toronto to visit the schooner  barge Sligo. The goal for the night? To complete a set of measurements for SOS Toronto’s wreck monitoring program. The winds were out of the south west which is not good for this site. With over 50 km of open lake for the wind to blow across there is a lot of wave potential. 

 The operation was based out of Toronto’s Outer Harbour Marina this night and we made a preemptive stop at the fuel dock to make sure were fully loaded with fuel. This serves two purposes, one being that we won’t have to refuel from the reserve tanks while pitching in what could be heavy seas, the other being increased weight down low makes for a more stable platform.

 Captain Bryan Thomas piloted his 27’ dive boat out to the Eastern Gap where we were met with some 3 foot rollers, the wind knocking spray off the tops of the waves. Deciding that a longer but gentler ride would be preferred he pointed the bow towards the Inner Harbour. With the shelter of Toronto Island on the port side and the buildings of downtown Toronto on the starboard we were in reasonably calm waters but required to make no more than 5 knots of headway. We enjoyed the dramatic sight of the impossibly large planes landing on the runway at Toronto’s Island Airport. They always look too big when flying right over your head.

 Entering the narrow Western Gap the waves reached even higher at over 5’. Just outside of the gap there was a small freighter anchored with a 100 ft tug tied up to the starboard side. We enjoyed a brief respite in the lea of the freighter for a few minutes and then it was back to the rollers. Once in the open lake things were a bit smoother and the wave period lengthened.

 Locating the mooring buoy we tied in, the SOS divers quickly geared up and splashed in first since they would be working without lights and before too long it would be dark. Us Liquid folks are a hearty bunch, but that didn’t mean we wanted to hang around on a pitching boat for any longer than we needed to. So we quickly donned our hoods, gloves, masks and fins. The gracious captain lifted our doubles and stages onto the bench and held them up for us to get strapped in.

 John Millar got in the water and waited in the rolling seas for me to get ready. Once I was all kitted up I joined him at the wickedly swaying buoy. Normally I would make final adjustments like tightening my harness and other last minute housekeeping items on the surface. Due to the conditions and my concern that the buoy might strike one of us I signaled to begin the descent.
 The first 15 ft was very milky and the visibility couldn’t have been more than 2 feet. Below that however the it improved to a whopping 15 ft. At the 45 foot mark things opened up but boy was it dark. You would have thought that we were hundreds of feet underwater not 70. My first thought was, how can those SOS guys see anything down here without lights.

 I signaled John to move to the stern and upon receiving a reciprocating signal we headed aft. About mid ship we came upon Dr. Taylor and Elaine Wyatt demonstrating their built in night vision goggles. There they were measuring away and scribbling on their slates. Reassured that they could see after all, we proceeded to the stern to locate the first on board datum. Upon dusting off the tag and confirming that we had the correct datum we proceeded to locate the aft starboard external datum.

 The external datums are long T bars pounded into the lake bottom away from but parallel to the wreck. There are three on each side of the Sligo. These create a static point from which we can measure to previously established points on the wreck. Each datum on the wreck itself is made from cow tags nailed into the ends of futtocks (curved hull frame timbers). Measurements are made from the leading edge of the T bar to the center of the nail head.

Cow Tag Futtock
Cow Tag and Futtocks

 John and I quickly got to work moving from datum to datum, carefully recording each measurement and its location. To achieve greater accuracy, four measurements from each external datum are taken. These measurements as well as those taken between the datums on the wreck itself will be compared each year to show changes in the ship as the wrecking process continues.

 Once I took the last measurement on the starboard side we checked gas supplies and bottom time. Well within the limits, we could have easily done the port side measurements. Thinking that the other divers were already on the surface in a pitching boat it was decided to call the dive. Many measurements were done and we had been quite productive. Getting a dual thumbs up we ascended to 50 ft.

 Since John and I are both in the process of taking an Advanced Nitrox and Deco Procedures course we had arranged ahead of time to do a simulated deco on an alternate gas. At 50 ft I signaled the gas switch, switched to stage bottles and waited out a one minute stop. The signal was given and we ascended to our 30 ft stop for two minutes. On the way to our 10 ft stop the viz was as bad as before and seas were a rollin. We managed the full four minutes only varying from 11 to 9 ft.

 On the surface John headed for the stern, I untied the boat whilst avoiding a bong in the head from the mooring buoy that was acting like one of those inflatable clown punching bags. Once the captain let me know that John was on board I released the boat and swam to the stern. Climbing the ladder in big seas is not easy with double 130s, an 80 stage with your fins still on. Once my but hit the bench, hands quickly flew over me to relieve me of my rig. I popped my fins off, raised the ladder and drew in the tag line with a spar buoy on it.

 Bryan got us quickly turned around and surfing on a large wave so that we would be stable enough to doff our dry suits. Out of the suits with all gear secured we headed for the cabin to join the other members of the team. John and I debriefed each other on the way in and by the time we reached the Western Gap we were lazily watching the lights of Toronto go by.

 The trip back to the dock through the inner harbour was uneventful and actually relaxing. As the boat rounded the corner and out the Eestern Gap, the captain gunned the throttle and we headed at over 27 knots towards the outer harbour. We made landing at 10:30pm, unloaded the boat and made for home.

 Special Thanks to Elaine Wyatt from SOS Toronto for inviting us to help with her project.

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About Chris Phinney

An IWMS Systems Manager and part time student at McMaster University. Chris is studying anthropology, more specifically archaeology working towards his BA. Chris was formerly a dive shop manager and is factory trained in regulator and equipment service. Chris enjoys research and studying fine details.