The Grand River Conservation Authority has issued a flood warning for parts of Cambridge and West Montrose.
The Speed River in Cambridge is expected to reach flows of above 50 cubic metres per second late Wednesday, exceeding the capacity of the Black Bridge Road bridge and the walking trail under Highway 401.
The bridge and trail are both closed under water levels.
Along the Grand River in West Montrose, the GRCA says water is already flooding the banks adjacent to the West Montrose campground.
By Friday, the GRCA expects water levels to exceed the riverbanks’ capacity.
Between 30 and 45 millimetres of precipitation have fallen across the Grand River watershed since Monday.
According to the GRCA, as much as 70 millimetres more could fall by the end of Friday.
The rest of the watershed remains under a flood watch.
Along the Nith River in New Hamburg and Ayr, water levels are expected to peak late Thursday, potentially affecting residents near Milton and Jacob streets (New Hamburg) and Tannery and Piper streets (Ayr).
The Nith will continue on and crest through Wolverton on Saturday.
The Conestogo River will peak in Drayton on Friday, with the Speed River peaking through Guelph around Friday morning.
Along the Grand River, peaks are expected through Grand Valley, Kitchener and Cambridge on Friday, moving into Brantford and Six Nations for Saturday.
Low-lying areas in Kitchener, including Bingemans Park, are expected to be flooded for the rest of the week.