Résumé :
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This study explores the feasibility of maintaining and resoring sediment damaged aquatic and riparian habitats throught managing reservior releases to flush deposits of accumulated stream bed sediments. Considered are : 1) classifying situations where controlled flushing or scouring culd be applied beneficially, predict or evaluate effects, and by purpose; 2) review of past sucesses or failures : 3) methods of predicting flow requirements : and 4) presentation of two case studies ( Platte R., NE and Trinity R., CA). Two major problems are thereliability of predictive methods and the prediction of sediment loads from disturbed watersheds. Development of flows sufficient to contend with armored or cemented substrates and well developed bank vegetation may be especially difficult because of technical, legal and cost constraints. In many situations controlled reservior releases will need to be combined with sediment management practices. Institutional probelms would likely include reservior project repayment contracts, water rights, court decrees, and interstate compacts in addition to reprogramming reservior operations. Technical considerations include the ecological need and environment trade-offs and site specific conditions including : watershed, flow regimen or bed composition, and channel morphology.
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