The Lower Thames Valley Conservation Authority (LTVCA) has issued a flood watch after significant rainfall over the past 48 hours.
It says over 15 mm of rain fell between 5 p.m. and 7 p.m. in Chatham on Thursday.
That brings the total rainfall over the course of the day to over 30 mm.
Some parts of the Upper Thames River watershed have received up to 55 mm since Wednesday.
The Upper Thames River Conservation Authority says the river and creeks are running very high and fast.
The LTVCA expects levels of the river to peak Sunday, causing issues in downtown Chatham and for residents who live along the Thames.
Residents are being asked to avoid the river and other waterways because of fast moving water.
The flood watch remains in effect until Saturday.
