Stream Restoration Essay examples

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Different physical structures may be used in stream restoration in order to provide channel stability and in order to provide habitat and other beneficial functions. Some of the typical structures that are used are revetments made of gabions or riprap and woody debris. Each type of structure has benefits and costs that should be considered before installation and some are more appropriate in certain situations than others. Gabion revetments are used to control stream bank erosion. Gabions are stone filled wire baskets that are placed along stream banks. The typical size of a basked is 3 feet wide by 3 feet tall and the length can vary. They are effective for protecting submerged portions of stream banks. They can be used when the slope…show more content…
Live fascines are most often used on longer slopes (The Ohio Department of Natural Resources). Another example of a type of structure used is an energy dissipater. An energy dissipater is any device created to protect the area downstream from erosion by reducing the velocity of the flow. An effectively designed energy dissipater will restore the flow downstream of the dissipater to a condition that is close to the natural flow regime. There are two broad categories of energy dissipaters, those that cause a hydraulic jump and those that are considered to be impact basins (Tennessee Department of Transportation, 2010). There are many other structures and techniques that are used in the field of stream restoration. The use of riprap is a common technique and there are examples of its use locally in San Diego. Additional structures may serve other purposes such as directing flow or providing habitat. Woody debris, for example can provide habitat to many animals. Root wads from trees provide excellent hiding areas for juvenile fish. The stream restoration design and stated objectives will determine what type of structures will be required to meet the stated project goals. Case Study-Forester Creek Forester Creek is a tributary of the San Diego River located in Santee, California. The creek flows northwest from El Cajon to beyond Mission Gorge Road (see Figure 2) (Hanna). Prior to the improvement project the creek was considered by some to
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