Water leaked and evaporated from the canal continuously, so the canal was always located near a natural stream to add water as needed. The feeder dam at Circleville was built in 1830 and added water to the canal as it flowed southward. A dam in the Scioto River increased the water level so that water could be routed through a weir to the feeder, which allowed the water to enter the canal below Lock 34, located under one of the houses south of the main entrance to Canal Park. The dam consisted of terraced levels that slowed the river current north of the dam to raise the water level to a point where weir gates could be opened and allow the water to flow into the feeder. In high water on the Scioto River, the locktender could close off the water flow to protect the canal from flooding.