A watershed is an area where water from rain or snowmelt drains from a high point into a body of water such as a creek or lake. In Colerain Township there are two major watersheds: the Great Miami Watershed bordering on the west side of the township and the Mill Creek Watershed, which is represented by the West Fork Mill Creek located on the east side.
Watersheds have a number of unique features including creek channels, flood plains, and riparian zones/vegetation. These features are interrelated and are important in water collection, water storage, and in maintaining creek health by helping to reduce soil erosion and by acting as a buffer to reduce the amount of pollution going into the water. Therefore, it is important to maintain buffer strips and to not mow them or cut them down.