Lock 23 Conditions: May 15

This should prove to be an interesting season at Lock 23.

COVID-19 aside, let me first review the current state of spring river conditions.

Recall that Morrisburg’s Lock 23 sits in the middle of “Lake St. Lawrence”, the 1959 body of water between Cornwall and Iroquois created when dams were constructed at either end. The Cornwall hydroelectric dam controls outflow from Lake Ontario (a long way away) which in turn makes Lake St. Lawrence rise or fall. The Iroquois dam controls local water levels to manage boating and shore issues for inhabitants along the river.

This winter was mild with manageable ice formation, allowing the International River Commission to dramatically increase river flows to help lower Lake Ontario. With no shipping or recreational boating going on, flow could be cranked up even higher than its safe maximum. This led to almost laughably low waters in Morrisburg in January – quite the experience to see. It came with extremely quick current and eddies , making conditions around the locks hazardous even for advanced cold weather divers.

Today the river remains low though not as low as in January. Shipping is moving normally in both directions. The dam in Cornwall remains wide open while the closed gates in Iroquois have raised levels a bit in our area. With this season’s slow, steady spring run-off both upstream and downstream, it appears that we may not get the severe flooding of the previous two years. To get an idea of flow, it helps to look more at the dials than the numbers themselves in the diagram below.

2020-05-13-web-lake-st-lawrence
from https://www.facebook.com/InternationalLakeOntarioStLawrenceRiverBoard/

Two diver friends of mine dove Lock 23 a couple of days ago. They noted that the current was relatively mild, visibility was 15-20 feet with the usual mess of early spring plant material floating along, and the water was cold (7C/45F). Brrrr!

Now… about COVID-19…

Morrisburg’s waterfront walking paths have never been closed but the boat ramp has been blockaded and signs erected to stay away from the public dock. The beach is closed. The two divers above waded in alongside the dock. Arriving separately in their own vehicles, they were able to check each other while comfortably self-distancing and it was easy to keep safely away from those sitting in nearby cars.

Parks are opening this weekend. The public dock entry area and the beach exit area will likely have lots of people around as restrictions are slowly lifted so it will not be easy for divers to self-distance unless groups are quite small. I don’t know any details of how they’ll get their tanks filled.

At any rate, the river is too cold for wet suits so there won’t be a big issue with groups for a while.

We can only wait and watch, as everyone knows. We’re in uncharted territory.

Sydney