The remote First Nation community of Kashechewan has officially declared a state of emergency.
Kapuskasing is the designated evacuation centre for all operations.
The town says 728 stage one evacuees will be arriving today, with hourly flights on the schedule.
The first 448 evacuees will be staying in Kapuskasing lodged at local motels with the rest being transferred to other communities.
The First Nation says the evacuation is precautionary as the dikes around the community have been assessed and are failing.
Stage one residents are vulnerable, such as families with young children, the elderly or those with health issues and concerns.
The evacuation is expected to continue into tomorrow.