It continues south, takes in the right tributary Smith Creek and arrives at the community of Nithburg.

The river turns south into the township of Wilmot, takes in the left tributary Bamberg Creek and passes through the communities of Phillipsburg and New Hamburg, Ontario.

The Nith River is flat water with a few riffles, but rain and snowmelt can significantly increase the flow rate.

[1] In the early spring the maximum flow rate reaches a median value of 30 and mean of 40, but commonly exceeds 200 m3/s, causing major flooding in the flat regions upstream such as in and around New Hamburg.

Wayne Gretzky stated on the April 26, 2022 episode of the podcast Spittin' Chiclets that the first time he ice skated was at 2 1/2 years-old on the frozen Nith River in his grandfolks' back yard.