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<br />lDWHAZARD <br />For a low hazard classification, the flood due to failure of the dam is judged <br />to cause no significant damage to manrnade improvements, other than the dam <br />itself, and no anticipated loss of life. Minor damage to unimproved county <br />roads and small irrigation structures is considered within the class of low <br />hazard, as well as sheet flooding of agricultural fields and farm out <br />buildings. The following criteria describe a low hazard classification; <br />1. Field reconnaissance shows no manrnade improvements of any <br />kind in or adjacent to the downstream drainage. It is <br />usually necessary to check the drainage until it intercepts <br />a larger stream capable of containing the anticipated flow <br />(QR) without overbank flooding. The required extent of <br />reconnaissance depends upon the size of the reservoir and <br />the height of the dam. <br />2. Calculations show the capacity of the channel at the <br />critical section (Qc) is sufficient to pass the routed peak <br />of the failure hydrograph (QR). Minor damage, as previously <br />discussed, is expected.. <br />3. The dam fails into a downstream reservoir without causing it <br />to fail, and no manrnade improvements are located between the <br />two reservoirs. In this case, the lower reservoir is <br />expected to fully attenuate the flood hydrograph. <br />~DERATE HAZARD <br />For a moderate hazard classification the flood due to failure is judged to <br />cause significant property damage and economic loss beyond that suffered due <br />to loss of the dam itself. However, loss of life is not evisioned. The <br />following criteria relate to moderate hazard classification; <br /> <br />21 <br />