Bluff erosion risk
Heightened risk of bluff erosion exists
The Ausable Bayfield and Maitland Valley conservation authorities say that saturated soil conditions are making some bluff areas along Lake Huron prone to collapse.
Recent rainfall and snowmelt have saturated the land and softened the clay till bluffs. This makes them more unstable. It can lead to slope failures along the shoreline and increased gully erosion.
Erosion along the bluff is a concern because it places structures and life at risk. Erosion at the bottom of the bluff destabilizes the bluff and leads to top-of-bluff recession. Erosion at the top of the bluff may occur in one large failure or in many smaller failures.
The two local conservation authorities are encouraging people to stay away from top-of-bluff areas in case there has been any movement of the lake bank. In some cases there may be a delay between erosion at the toe (bottom) of the bluff and subsequent bluff failure.
“Bluff failures are very unpredictable in terms of when they will happen or how extensive they will be,” said Geoff Cade, Water and Planning Manager at Ausable Bayfield Conservation Authority (ABCA). “We are encouraging people to be very careful and not get too close to the edge of the bluff.”
Conservation authority staff are discouraging residents from walking along those shoreline areas where a beach is accessible below bluffs. Injury or loss of life could occur if a bluff collapses and beach users are below that bluff failure.
Ausable Bayfield Conservation Authority and Maitland Valley Conservation Authority (MVCA) recommend that landowners check their shoreline property, when possible, to look for signs of erosion. Bent or leaning trees and a lack of vegetation on the slope are among the signs that your property may in an area of erosion.
The ABCA and MVCA can provide landowners with mapping indicating the erosion risk in their area. If you see a significant crack running parallel to the shoreline, contact your local conservation authority. A crack running parallel to the shoreline is one of the signs a failure may occur.
You may reach ABCA at 519-235-2610 or info@abca.ca and you may reach MVCA by email at maitland@mvca.on.ca or by phone at 519-357-6670.
You may also find out more at abca.ca and mvca.on.ca.