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Nature Link

With Blake Mann

The Power of Ice

Tuesday, February 4, 2003

With the recent "real winter" weather, we have had ice conditions not seen for a few years. We have been spoiled with mild winters in recent years. It is obvious that there is something to this global warming idea. When I was younger, there was always lots of snow, and the rivers and lakes were frozen for long periods of time. Even previous to that, my grandfather talked of long winters of deep snow, and ice on the river two to three feet thick.
Ice can create problems when it starts to "move". In the spring, the Sydenham River is known to be high and fast flowing during the spring thaw and ice break-up. Ice jams, complete with debris picked up along the way, can cause flooding. That is how our past floods occurred. In the flood of 1968, an ice jam developed downriver somewhere on the lower reaches of the Snye River, and forced the water levels to rise quickly for a few days.
It is interesting to note how the Snye reacted. I am told the Snye completely reversed its flow. It normally begins flow at the St. Clair River south of Port Lambton, and continues out towards Mitchell Bay or out the Johnston Channel. In this case due to the blockage of flow, it reversed course and flowed INTO the St. Clair River. It is a deep-flowing watercourse, and due to the flatness of the topography, it is easy to understand. Even during the high flows of spring run-off, the Snye will still reverse its flow from the outlet of the Sydenham towards the Johnston Channel entrance. All the water flows out the Johnston, and I have seen this many times early in the spring. As a side note, Running Creek frequently reverses its flow. During normal times, Snye water flows through it to the Sydenham. During high flow periods, the Sydenham north branch flows into Running Creek, and hence into the Snye.
Back in April of 1984, a unique condition developed on the St. Clair River due to ice blockage. The mighty St. Clair essentially stopped flowing for several days. The winter of 1984 was quite cold, and lots of ice had developed. In the spring thaw, tremendous amounts of ice came down from Lake Huron, driven by persistent northerly winds. It began jamming in the lower reaches of the St. Clair River and continued to jam. The ice packed itself right to the bottom and built upon itself. This was the time when shipping was getting active after the winter. Many ships were fooled by the ice, and became stuck or were sent aground. The ice was so powerful, that it forced ships out of the channel. This, coupled with the fact that water levels were quite low due to the lack of flow, caused the ships to bottom out.
I remember arriving at Port Lambton on Friday, April 13, 1984, and seeing the ships at a standstill. I counted 18 freighters or Coast Guard vessels from Walpole Island to Fawn Island. The accompanying photo shows several ships on that day at Brander Park, Port Lambton. The ship at the far right was actually aground and had a list to port. Some of the less powerful ships were forced backwards even though they were at "full ahead" and had both bow anchors down. This alone attests to the power of moving ice. Some ships scraped each other during this uncontrollable situation. This was the worst day of the situation, and the ominous black sky in the background, as seen in the photo, gave it the nickname "Black Friday". It took over a week to clear the backlog, and the ice lasted right until the end of April. In fact, I think there was still some ice in early May.