Multi-log Deflector

A Multi-log Deflector is a habitat improvement device that will serve to narrow an unnaturally widened stream as well as providing habitat. A Multi-log Deflector can be appropriately used in a riffle, run or pool habitat, but should not create a dam-like effect on the stream. These devices are used to encourage a stream to recover a more natural meander pattern (the natural bending of the stream) while also providing multiple forms of habitat. These devices are constructed in the basic shape of a right triangle with the right angle (90°) being out in the stream. The materials used to construct these devices are hardwood logs and larger stone. To complete the right triangle design, there is an upstream log and a downstream log. Both logs should be trenched into the stream bank and anchored in the trench with stone. This device can be constructed with the upstream log resting on top of the downstream log or the reverse depending on the desired effect. The logs can be optionally pinned to the stream bottom, but should always be pinned to one another using re-bar fastened through both logs at the right angle tip of the deflector. In the case of the upstream log resting on top of the downstream log, oak planking can be installed on the upstream log as flooring to create a large amount of overhead cover. In this case, the oak planking would be covered with stone and a layer of soil and then seeded and/or planted with native vegetation. If oak planking is not desired or available, simply using two logs side-by-side on the upstream end will create adequate overhead cover. In this case, both logs should be pinned to the downstream log. Filling the deflector with stone, covering the stone with a layer of soil, and planting native vegetation are still appropriate for the second technique. If the downstream log is rested on top of the upstream log (the reverse of the above situations described) a slightly different desired result will be achieved. This device will provide habitat in the form of a scour pool at the tip of the downstream log, ideal for young and small fish. This device encompasses no flooring and a small amount of overhead cover provided by the downstream log. The device constructed in this manner will encourage gravel and sediment to settle on the deflector, narrowing the stream channel. These devices, constructed in either fashion described, will protect stream banks from erosion, create a more defined stream channel, and provide habitat.

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