The Upper Thames River Conservation Authority has issued a warning as watershed levels will be approaching the top of banks in some areas.
The authority says residents in watershed areas should use extreme caution near all watercourses and keep pets and children safe.
"Water in streams, creeks and the Thames River is fast moving and cold and bank areas can be slippery", UTRCA says in a release.
Most parts of the Upper Thames River watershed received 15 to 30 millimetres of rainfall Saturday on top of the 10 to 30 mm received earlier in the week.
The highest rainfall totals were received in the north part of the watershed, the authority says.
The additional rainfall is producing the highest stream flows since spring of this year in the majority of watershed water courses.
The Thames River in London is expected to peak overnight Sunday and into early Monday.
However, serious flooding is not expected, the release says.
