Graham & Wilmot Creek Flood Plain Mapping Update

The Ganaraska Region Conservation Authority (GRCA) partnered with the Municipality of Clarington to update flood plain mapping for the Graham and Wilmot Creek watersheds. Flood plain mapping helps to identify areas that may be at risk of flooding during severe storms and is an important tool for land use planning and emergency preparedness.

The study area covers the Graham and Wilmot Creek watersheds, which includes Newcastle Village, Orono, and the Hamlets of Brownsville, Leskard, Starkville, Clarke, and Newtonville. Residents can view the presentation video from the March 20th, 2023 meeting, as well as view the Mapping Interface of draft flood plain changes using the links below.


Important Notice: The 2023 draft mapping is being uploaded on March 8th, 2023. Until then, residents are welcome to familiarize themselves with the app and to view properties with the existing floodplain mapping from 1977.


Graham & Wilmot Creek Flood Plain Map

Project Timeline & Status

Spring & Summer 2021 Summer 2021 – Summer 2022 Fall 2021 – Winter 2023 Winter 2023 Winter – Spring 2023 End of March 2023
Background Data Review Field Survey of Structures GIS Data & Model Development Report & Map Production Public Information Centre Project Completion


For further information about this study, contact the Project Technical Lead:

Cory Harris, P. Eng.
Watershed Services Coordinator

Ganaraska Region Conservation Authority
905.885.8173 ext. 226