A flood watch has been upgraded to a flood warning for the Maitland and Nine Mile River watersheds.
Although much of the snowpack is gone, the ground remains frozen in many areas and the rain is expected to run off quickly. Water levels in streams and rivers will continue to rise on Wednesday.
The Grey Sauble Conservation Authority also issued a flood warning for the Sauble River, Bighead River and Beaver River watersheds.
There's a flood watch for the rest of the Grey Sauble watershed. The conservation authority says the water systems appear to have peaked but most flows are still exceeding average spring runoff conditions.
A flood watch remains in effect for across the Saugeen Valley Conservation Authority watershed.
Water levels will continue to rise on Wednesday. Ice jams will be moving in response to the increasing river flows and could create localized flooding downstream.
The situation is very similar in the Grey-Sauble, and Ausable Bayfield watersheds. And the Grand River Conservation Authority issued a flood warning message for the Township of Mapleton, Drayton and Township of Woolwich, West Montrose.
The OPP are asking motorists to avoid driving through roads submerged in water.
At least two dozen rural roads across Perth, Huron, Bruce, Grey and Wellington counties are flooded or washed out. Road Closure signs are posted, and detours are in effect for local traffic.
Police are reminding drivers that it's extremely difficult to judge the depth of water on a roadway. Six inches of moving water could be enough to easily wash you and your vehicle off the road.
Meanwhile in Brantford, police there are going door-to-door in the neighbourhoods of Holmedale, Eagle Place and West Brant urging people to leave.
The area is being evacuated now that the Grand River is spilling its banks. An ice jam let go around 2am Wednesday morning, sending a surge of water downstream.