Maitland Valley Conservation Authority Updates Shoreline Hazard Mapping
by Bob Montgomery
The Planning and Regulations Supervisor for the Maitland Valley Conservation Authority recently brought Goderich council up to date on what they've done so far in developing coastal resilience and what they hope to do in the future.
Patrick Huber-Kidby says early in 2021 they started updating their shoreline hazard mapping and that mapping was approved in October. Huber-Kidby says that mapping is unique in that it's the first in Ontario to incorporate the impact of climate change in the fifty kilometres of shoreline in the Maitland Valley watershed. He says they've also been getting out and talking to people who live in their watershed about what the hazards are and how the community can become more resilient to them. Huber-Kidby says on the lake side of the erosion hazard there is three-quarters of a billion dollars worth of property, so land, homes, roads that are expected to be impacted by erosion sometime in the next hundred years. And he adds, those erosion rates are escalating, primarily because the winter ice cover on the lake is decreasing significantly because of climate change and warmer temperatures, so the shoreline is more vulnerable to erosion.
Huber-kidby says they don't have the data yet to confirm it, but anecdotally, stronger winds and more intense precipitation events as a result of climate change are also contributing to the problem. He says slowing the process of erosion down is very difficult and generally speaking in any battle of attrition with Mother Nature, Mother Nature tends to win.
Huber-Kidby says they have applied for funding to help them run a few pilot programs and they'll know next year if they've been successful in getting that. He says they'll be looking at three main things. One is development policies and how those policies are working now, and whether they need to be modified to facilitate the resilience on their coastal communities and not create situations where they're exacerbating hazards. They're also looking at creating a manual for a planned retreat in the event that roads or homes do start to erode and what they should do in that situation. And the third project is creating a sediment by-pass around the town of Goderich. He says sediment that has eroded usually travels north to south and the sediment that travels south along the Lake Huron shoreline provides beaches further south. But he says the harbour infrastructure in Goderich prevents a lot of that sediment from travelling south and that sediment is currently being dredged and deposited in land or taken out further into the lake. They're proposing to take that sediment around the town and put it back into the lake where it can drift further south and feed more beaches.
