Media Release

RVCA Launches Tay River Floodplain Mapping Project
— Local Input Welcome

TAY RIVER WATERSHED, June 22, 2012 — The Rideau Valley Conservation Authority (RVCA) has started a floodplain mapping project of the Tay River from Glen Tay Road to Lower Rideau Lake. The project will identify flood prone areas along the river — areas that are expected to be inundated during extreme flood events.  Floodplain limits, once determined through engineering analysis, are then used to support appropriate land use planning and infrastructure design, in accordance with Provincial policies.
 
Using the latest hydrologic and topographic data and well-established practices in water resources engineering, the 1:100 year flood flow, regulatory flood levels and corresponding floodplain limits will be estimated throughout the study area during this project.
 
In Eastern Ontario, the Regulatory Flood Standard is the 1:100 year flood event – defined in regulations as “rainfall or snowmelt, or a combination of rainfall and snowmelt producing at any location in a river, creek, stream or watercourse, a peak flow that has a probability of occurrence of one per cent during any given year”. The water level associated with the 1:100 year flood is called the regulatory flood level and the area inundated during a 1:100 year flood is called the floodplain.
 
Floodplain limits are determined by estimating the flood flow at various points along the river, using any available historical streamflow and water level data collected over the years, along with state-of-the-art watershed modeling tools.
 
Historical records of past flood events, news clippings, photographs, and even anecdotal stories can be helpful in confirming the reasonableness of our calculations and resulting floodplain mapping. Local residents with this kind of information are encouraged to share their knowledge with RVCA’s Stephanie Schreiner (1-800-267-3504 ext. 1104 or stephanie.schreiner@rvca.ca). Those interested in learning more about the project or being included in our contact list are also encouraged to contact the RVCA.
 
The last floodplain mapping in this area was completed in 1981and covered the river from Glen Tay Road to the Tay Marsh. Now 30 years old, the maps need updating. No flood plain mapping has ever been done for the river downstream of the Tay Marsh. The current project will replace the old mapping and produce new mapping downstream of the Marsh. The RVCA finished mapping upstream of Glen Tay Road to the Christie Lake outlet in 2009.
 
Once the technical work is completed and floodplain mapping has been prepared, a public information session will be held (Fall 2012) where feedback from the public will be invited. Any new information or comments received will then be taken into consideration in further refinement of the mapped flood plain limits.  A Report will then be presented to the RVCA Board of Directors, recommending formal adoption of the flood plain limits and their use in RVCA’s land use planning and development review services.

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For more information, contact:
Stephanie Schreiner
RVCA Engineering Assistant
1-800-267-3504 ext. 1104
stephanie.schreiner@rvca.ca