From the Niagara Falls Review:
The prolonged weakness of the Canadian dollar means people paying more to cross the border.
Effective May 15, Canadian tolls for passenger vehicles will be increased to $4.00 Cdn from the current $3.75 rate. The U.S. tolls will remain at $3.25 U.S.
The Niagara Falls Bridge Commission, which operates the Rainbow, Queenston-Lewiston and Whirlpool Rapids border crossings, says the move is not a toll increase, but rather an exchange adjustment, which is “entirely based on U.S. currency and its exchange rate with the Canadian dollar.”
The adjustment will include passenger vehicles using the discounted Canadian Express Pass as well, with the newly adjusted toll being $3.40 Cdn.