Saw-tooth Rock Deflector
A Saw-tooth rock Deflector is a habitat improvement device that also provides some stream bank stabilization. This is a device that is actually a series of devices creating areas of pocket water (slower moving backwater or re-circulating water) next to the stream's edge. These devices can be appropriately installed in most habitats such as riffles, runs and pools, but are usually installed on the outside of a bend in a stream. Saw-tooth Rock Deflectors are designed as a series of right triangles (90° triangles) made of large stone that will not be moved by the force of the stream's flow. The device operates on the principle that water will flow over immovable objects at right angles. As water rises and flows over the downstream end of each deflector, the force of the water is directed vertically down into the stream bottom creating a scour pool (a deeper pocket created in the stream bottom). The pocket water areas created by this device also serve as slower moving sections of water out of the main flow of the current. These two conditions combined make these areas ideal for smaller fish to rest in and feed from without tiring. After installation of the device the stone used to create the device can be covered with a layer of soil and seeded/planted with native vegetation to ensure protection from future stream bank erosion. When plantings are combined within the rock used to form this device, a natural appearance along the stream bank can be achieved fairly quickly.
