The Casselman dam ruins are fairly interesting to see as they played a large part in the growth of the city. The ruins are unstable at some spots and it seems they a removing and restoring certain aspects of the dam.
The following Historical information is provided and written by Hydro Ottawa.
1908 - J.N. Coupal, a businessman in the Village of Casselman, begins construction of a 460 foot dam across the Nation River and a 125 kW powerhouse to provide electricity for his flour mill, his home and neighbouring homes. When the project is completed two years later, the local council grants a 30-year franchise to Mr. Coupal to supply electricity to the rest of the village. But customers can only use electricity between 4:00 p.m. and midnight to ensure there’s enough river water to power the flour mill during the day.
1922 - J.N. Coupal closes his flour mill in Casselman, increasing the supply of electricity to the village. Demand had increased so much that some new residents were on two-year waiting lists to receive power.
1924 - The Village of Casselman forms its first local power commission and enters into a new ten-year contract with J.N. Coupal to supply power to the village. The contract stipulates that all surplus money must be refunded to customers. As a result, customers in Casselman receive their power for free during November and December every year for the next ten years. When the contract expires, the village resumes the terms of the 30-year contract negotiated in 1912.
1952 - The demand for electricity in Casselman now exceeds the capacity of J.N. Coupal's system so the Village launches a publicly-managed utility called Casselman Hydro. HYDROOTTAWA.COM