Highlights:

• Current water levels on the lakes are well above average and slightly below where they were this time last year.
• Sustained wind speeds above moderate and/or heavy rains could cause flooding, erosion, and shoreline damage.
• Risk of wave spray flooding along the shorelines of both lakes.
• Risk of erosion and damage to shoreline protection works on both lakes, including erosion along the high bluffs.
• Once temperatures drop, but before the lakes freeze over, there is a risk of icy conditions in shoreline areas when wave spray and flood waters freeze.

Message:

Average daily water levels on Lake Erie at the beginning of November were around 174.65 m (I.G.L.D.). This is down about half a metre from this year’s peak daily average water level record set at the end of May. The average water level for the month of November last year was 174.68 m. Water level forecasts are currently predicting a drop in lake levels of 8 cm over the month of November.

Average daily water levels on Lake St. Clair at the beginning of November were around 175.64 m (I.G.L.D.). This is down about a half metre from this year’s peak daily average water level record set during the third week of May. The average water level for the month of November last year was 175.71 m. Water level forecasts are currently predicting a drop in lake levels of 5 cm over the month of November.

Current water levels on the lakes are still well above average. While they may have dropped around a half metre from their peaks in May, they are only slightly below where they were around this time last year and slightly above where they were around this time in 2018. Therefore, the risk of flooding and other shoreline damage remains very similar to what has been seen over the last few years. These risks will remain until winter conditions cause the lakes to freeze over.

Sustained winds can cause an effect known as setup where water from one end of the lake gets pushed to the other, creating a rise in water levels at the far end of the lake. This had been one of the main reasons the community of Lighthouse Cove was seeing flooding from the canals. Given that water levels on both lakes have now dropped around a half metre since their summer highs, there is very little risk of direct flooding in shoreline areas due to lake setup. Wave spray will continue to be the main source of flooding along the LTVCA shorelines, which will still be determined by the wind speed, wind direction, and the waves they create.

Strong winds out of any direction could have an impact on some areas along our local shorelines. In the most vulnerable areas such as Erie Shore Drive in Chatham-Kent wave spray related flooding can begin at wind speeds as low as 30 km/hr, while other less vulnerable areas may need wind speeds closer to 45 km/hr. Gale force winds of 60 km/hr could be expected to cause significant flooding and shoreline damage to any low lying shoreline area. The area’s most frequently impacted communities and the relevant wind direction include: Lighthouse Cove when winds are out of a north through west direction; Erie Shore Drive when winds are out of the south (SW through SE); the bay side of Erieau when winds are out of a north through east direction; Shrewsbury when winds are out of the east (NNE through ESE); and Rose Beach Line when winds are out of a south through northeast direction. Of course, other shoreline areas are also susceptible.

Erosion and shoreline damage continue to be concerns as well. The same waves that cause wave spray flooding can damage shoreline protection works and cause erosion in unprotected areas. The bluff areas all along the Lake Erie shoreline are also at a greater risk of erosion due to the high lake levels, especially when there are onshore winds and waves. Along the bluffs, the erosion can cause the bluffs to fail and there have been instances of land many metres deep falling into the lake all at one time. Such failures do not necessarily occur during a high wind and wave event and exactly when the bluff may collapse is not something that can be predicted.

Heavy rains could also cause flooding in low lying shoreline areas. Due to the high lake levels, the groundwater table is high and storm water sewer systems and local watercourses are full with lake water. As a result, rainwater is not draining properly from these areas. Any water from upstream making its way downstream on local watercourses into these shoreline areas could cause additional flooding.

By the end of November, overnight temperatures are expected to start falling below the freezing point. Until the lakes freeze over, there will continue to be a risk of wave spray related flooding. When air temperatures are below the freezing point, wave spray could freeze onto shoreline structures, nearby homes, the ground, or even nearby roadways. In the past, this situation has led to cottages along Erie Shore Drive becoming encased in ice, which presents various risks to residents. Over the last couple of years, floodwaters have frequently made their way onto the roadways in Lighthouse Cove and onto Erie Shore Drive. This could create very icy and treacherous conditions for walking and travelling in shoreline areas.

Please contact your local municipality should significant flooding and/or erosion events occur, or should events occur that may impact roadways and other public infrastructure. If there is an imminent risk to personal safety, call 911.

Shoreline residents need to pay attention to local conditions and prepare accordingly. Most importantly, people need to keep themselves safe. Should an event occur, people should take extra caution and avoid the shoreline and any waterways with elevated water levels. The waves on the lakes can be strong, and the shoreline and the banks of waterways can be slippery and unstable. There could also be hazardous debris within the waves and water which could be thrown onto the shoreline. Standing water can also present unseen hazards. Children and animals should be kept away from the water.

This is a standing message issued for the months of November and December. Should weather forecasts suggest a sustained wind event likely to cause shoreline issues, this message will be upgraded.

Message Contact: Jason Wintermute ([email protected])