Zebra Mussel (Dreissena polymorpha) and Quagga Mussel (Dreissena rostriformis bugensis) have a long history of invasion in European and North American freshwater ecosystems, with significant ecological and economic impacts. An ecological risk assessment for these two invasive species for freshwater ecosystems in Canada was completed in April 2022 with the aim to provide science-based guidance to inform management decisions and actions. These include early detection, response planning, and/or regulatory and policy measures aimed at mitigating the potential spread and risk posed by Zebra and Quagga Mussels to Canadian freshwater ecosystems (DFO 2023). The Potential for Introduction (propagule pressure and connectivity), the Potential for Establishment (habitat suitability, including a Calcium-based and Maximum Entropy (MaxEnt)-based model), the Potential for Invasion, and the Ecological Impacts were used to derive Ecological Risk for Zebra and Quagga Mussels in Canada. This assessment did not evaluate the risk to individual waterbodies but rather was conducted at a 9,260 m x 9,260 m grid cell resolution. These high resolution maps are provided here. Maps of Ecological Risk at the sub-drainage level are also provided. Fisheries and Oceans Canada is not responsible for any omissions or errors that may be contained in this dataset and shall not be liable for any losses, financial or otherwise, due to the use of these data. Please credit Wilcox et al. 2024 as the source of the data in any maps, reports, or articles that are printed or published on paper or the Internet.