Saturday, August 12, 2017


The Grand River Conservation Authority (GRCA) have produced an eleven page report on the June 23, 2017 Flood Event. I assume that it is on their website although I received it from another source. I would describe the report as quite comprehensive, well written and pretty easy to understand. It includes Figures and Tables which truly give one the big picture and context in regards to how much rain descended, in how short a time and over how large a geographical area, all within the Grand River watershed. The numbers really are staggering.

That all said it has been a learning experience. Yes more can and needs to be done. Of that the West Montrose and other flooded citizens can be thanked for yelling loudly and clearly. No it's not likely nor even beneficial to magically lessen rainfall nor is it likely that "reservoir operations" during the downpour can ever actually prevent flooding. What can be done though seems to be twofold namely better weather forecasting and then quicker more accurate downstream communications.

The first aspect of weather forecasting is not directly part of the GRCA's mandate. This is up to Environment Canada and the provincial Ministry of Natural Resources and Forestry (MNRF). At this time it is unknown as to why those two bodies did not have any idea of the upcoming severity of the storm and quantities of rainfall. Perhaps the science of weather forecasting, like medicine, knows a lot but doesn't yet know what it doesn't know. Continued and ongoing research are required.

Downstream communications is crucial but this report also identifies communications upstream or more precisely upgradient. Most of our weather comes from the west. Communications between the GRCA and other Conservation Authorities to the west of us could give significant additional advance warnings of severe storms and rain. Hence warnings could actually go out before the rain has already started flooding rivers and low lying areas in our watershed. This seems like a really good idea.

While this is an excellent report there are a few items of which I am skeptical. These include estimates of the percentage of flow reduction that occurred courtesy of the various dams on the Grand, Conestogo and Canagagigue. Allegedly the flows through West Montrose were reduced by 32% thanks to the Shand Dam. The GRCA also appear to be taking credit for the fact that the Covered Bridge wasn't washed away or badly damaged. Again I'm skeptical. Perhaps the original builders of the Covered Bridge in West Montrose deserve credit for having built the Bridge so far above the normal elevation of the Grand River at that point.

Other than a little bureaucratic back patting it does appear that the GRCA are taking this very seriously and have come up with some communications improvements.

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