The Bywash and Bridges
What is now the bywash (or waste weir) was once the outlet for rapids which were 304 meters (333 yards) in length and dropped about 4 meters (13 feet). For boats to travel between Indian and Opinicon Lakes a lock was required to circumvent the rapids. Now water flow through the bywash is controlled by stop-logs south of the bridge over the bywash. The mill used this water flow to operate. Although the original Chaffey’s Mills had a bridge over the rapids it was too low to allow vessels to pass beneath it and Col. By had it removed. During the first years of the mill’s operation no bridge existed over the lock and bywash. Local farmers ferried their grain across to the mill. A foot bridge was available by the 1880s. A wooden swing bridge built over the lock was replaced by a steel swing bridge in 1949. That bridge was replaced in 2015 by the present steel swing bridge of similar design.