Flood warning maps could help
Flood warning maps could assist municipalities
Wet ground conditions could lead to runoff during storm event, meeting told
Flood warning zone maps could assist municipalities in notifying people, living in areas where flooding is the worst, during a severe flooding event. Emergency coordinators heard this at a Flood Emergency Planning Meeting hosted by Ausable Bayfield Conservation Authority (ABCA) on Thursday, February 23, 2017.
More than 20 municipal officials, emergency coordinators, and reporters attended the meeting which was held at the Masonic Hall in Exeter. Featured speaker Gus Rungis, Senior Water Resources Engineer with Grand River Conservation Authority (GRCA), spoke on the development of flood warning zone maps at his conservation authority.
The keynote speaker shared photos of a number of flood events that have hit New Hamburg and the Nith River system. The presenter said the GRCA has developed maps to identify where flooding may be the most severe in that area during different storm events and where that flooding might impact properties and roads the most. The maps and property lists assist municipalities in knowing whom they should contact directly in a flood emergency event.
Other speakers at the meeting included Davin Heinbuck, Lands and Water Technologist with ABCA, presenting on current watershed conditions and roles and responsibilities in the ABCA Flood Emergency Plan; and Ross Wilson, ABCA Water and Stewardship Technologist, presenting on testing of the ABCA’s flood message system.
The attendees at the meeting heard that a warm 2016-2017 winter has meant there is less snow cover and ice so there are fewer concerns this year with ice jams or rapid snowmelt. Municipalities should still be prepared, however, in case winter snowstorms or heavy rain events return, Heinbuck said. Even though there is little snow and ice, the ground conditions are wet and heavy rains are likely to run off the ground. “The greatest danger right now is heavy rain,” he said.
The ABCA has conducted a number of recent tests of its flood message communications, Wilson said. The tests have shown that municipalities respond in less than an hour, and often much sooner, when they are required to confirm that a flood message has been received. ABCA issues flood messages to municipalities by fax and email but municipal feedback shows that email is becoming the preferred means for them to receive a flood message, according to Wilson. A revised Flood Emergency Plan for 2017 is to be released shortly.
Municipalities create emergency plans and the Ontario Ministry of Natural Resources and Forestry (MNRF) plays a lead role during a flooding emergency but conservation authorities play an important role monitoring watershed conditions, interpreting forecasts, and sharing with municipalities what local impacts there might be to an approaching flood event. ABCA can warn municipalities if a flooding event is likely to be minor or major and provide technical and planning assistance. The conservation authority’s flood forecasting and warning program can help to minimize property damage, social disruption, and help to prevent loss of life. ABCA issues three levels of flood messages: Watershed Conditions Statements (flood outlook and water safety); Flood Watches; and Flood Warnings. The terms used by the conservation authority now match those used by Environment and Climate Change Canada: 1. Statement, 2. Watch, and 3. Warning.
Those taking part heard that ABCA monitors weather and watershed conditions including streamflow at local stream gauge stations and river levels; measures snow cover and water equivalent in the snowpack; and gathers information through river watch reporting on local rivers and presence of ice. The presenters showed examples of communities prone to flooding in the Parkhill Creek watershed and Bayfield River and Ausable River watersheds. The return of higher lakes levels is causing erosion along lake banks and beaches and may affect lake bluffs, the emergency coordinators were told.