Along with anyone living in southern Ontario and Quebec this spring, we’ve been watching carefully the weather reports and specifically rainfall statistics… and we’ve been driving up and down the shorelines to inspect areas we know. There has been flooding and damage to many, many riverside properties.
Lake Ontario levels remain higher than at any time in the last century and the International Lake Ontario-St. Lawrence River Board is carefully releasing the extra volume at as safe a rate as possible – to reduce water levels along affected shorelines while still protecting Montreal from flooding. They expect it to take several weeks. We’ve learned a lot about the strain this has put on international shipping: freighters have difficulty maneuvering upstream against the dramatically increased current and are in constant contact with authorities regarding conditions.
Morrisburg itself is protected from extreme water level changes by the dams 12 km upstream at Iroquois and 40 km downstream at Cornwall. Therefore the water level at the Lock 23 site is virtually unaffected. It’s the current that has dramatically changed dive conditions, and ongoing rainy days are causing an accumulation of additional sediment.
- FAST CURRENT on the approach drift in the canal. Normally it takes about 15-17 minutes to drift from the entry point to the lock gates. Yesterday it was fairly normal in the centre but much, much swifter at the edges – it took a mere 7 minutes on the inside drift to the Hydroelectric Plant sluice gates.
- EXTREME CURRENT at the gates. Normally divers can stop at the gates and check on buddies, etc., before going up and over whatever wall they’ve arrived at. At present it is extremely difficult to do so – divers are easily swept up and over the gates by the current.
- MODERATE CURRENT on the exit swim. Normally there is no current at the end of the locks and on the way out – divers set their compasses to NNE to consistently exit at the beach. We are currently swimming at a NW (and occasionally almost W) setting to reach our planned exit point.
- EXTREME BACK-EDDIES and whirlpools in the locks themselves. It is difficult even on the river bottom to move against them – feeling suddenly like you’re battling that current upriver. It settles as you move downstream but it can be very fatiguing.
- SILT HILLS where you don’t expect them… like on the wrong sides of gates! Likely this is due to back-eddies.
- POOR VISIBILITY. Sediment and stirred up waters has reduced visibility on occasion to 5-8 feet.
On the bright side… it’s early in the season and there are ALMOST NO WEEDS!!
All of this provides a new environment for divers – it can be a tremendous amount of fun if (1) you are experienced with currents, (2) you are comfortable working with the currents and eddies, letting them on occasion carry you over and beyond a difficult spot, (3) you know the landmarks and layout of this dive site and can proceed from where the current has set you down, and (4) you have excellent air management even with increased physical demands.
At this time, therefore, it should be considered an appropriate dive site for experienced, advanced divers only who have excellent air management, good lights, a compass and a surface marker buoy for use on the exit swim (DON’T try using it in the locks!).
Good diving to you!
Feel free to email me if you have any questions!