The Lower Thames Conservation Authority has issued a flood watch for several areas downstream of London.
The Thames River watershed received 35 to 55 mm of rain earlier this week, and forecast models predict more precipitation this evening.
Low-lying areas next to the river are already flooded from Delaware to Chatham, and the level of the river is expected to continue to rise.
In London, the river height peaked on Thursday evening, however the peak is expected in Dutton this afternoon, Thamesville tomorrow, and in Chatham tomorrow evening.
Although river levels in Thamesville will be high, the community is expected to be largely unaffected.
In Chatham, water levels could rise as much as another metre, with the Lower Thames Conservation Authority expecting that the 6th Street Dam will likely need to be used to mitigate flooding impacts.
Flood waters are expected to get up to the parking lots along the river between 3rd and 5th Streets, and into the yards of properties that back onto the river.
Water levels will likely remain high into mid-week.