KAWARTHA LAKES-A study of the underwater depth and mapping of the Burnt River began on Sunday, June 25 and will continue for the next month.
J.D. Barnes Limited was awarded the contract by Kawartha Conservation and the project will look at approximately 20 kilometers of river from the Village of Burnt River to Cameron Lake.
“In partnership with the City of Kawartha Lakes, we are undertaking a special project to complete flood plain mapping of the Burnt River watershed,” explained project lead, Kawartha Conservation Floodplain GIS/Mapping Technician Galen Yerex. “In order to complete this work, hydraulic and hydrologic modeling must be completed which requires a bathymetric survey of roughly 20 kilometres of the Burnt River, from the Village of Burnt River to the outlet into Cameron Lake.”
Bathymetric Modelling will be used to project future flood levels. “When the bathymetry surveying and mapping is complete we will be able to generate the computer models which will develop the updated flood plain mapping,” said Mr. Yerex. “Once complete, the updated mapping will assist both the municipality and the Conservation Authority with future planning and regulations to help ensure resident safety as new development occurs.”
Preparing mapping involves a combination of field work and computer modelling. Background data such as land use, topography and precipitation is gathered. This information is then used to build a computer model that calculates flows during storm events at various locations along the Burnt River system. The standard of protection is to the 1 in 100 year flood event, also called the regulatory flood. This is the event that has a one per cent chance of occurring in any year or a one per cent probability.
The water level information generated by the model is then applied to mapping of the Burnt River system. The resulting information is a floodplain map showing the regulatory flood level of a 1 in 100 year flood.
Conservation Authorities in Ontario are legally mandated to ensure that development does not occur in areas that are susceptible to flooding and erosion. Building in these areas can result in damage to properties when flooding or erosion occurs, and in extreme cases can result in loss of life. Updated flood plain mapping is used to prepare official plans and zoning by-laws, which guide future development in municipalities.
“Flood plain mapping is used by our staff when reviewing development applications,” said Mr. Yerex. “They are also used for our Development, Interference with Wetlands and Alterations to Shorelines and Watercourses Regulations (Ontario Regulation 148/06).”