Using River2D Morphology to Predict Salmon Redd Survival during High Flow Events from Hydroelectric Dam Operations

摘要

Flooding related to hydroelectric dam operations may be the result of increased inflows to reservoirs, natural events, and operational or structural failures and can cause significant impacts to downstream fish populations and their habitats. River2D Morphology (R2DM), a 2D hydrodynamic, morphology and gravel transport model is adapted to predict the survival rate of salmon redds during high flow events using a unique algorithm based on depth of redd burial. For a study of a reach downstream of the John Hart Dam on Campbell River in Vancouver Island, British Columbia of both controlled and uncontrolled operational high flows the predicted losses are 13, 42, 45, and 50% for events with return periods of 2 - 8 years, 20-year, 100-year and 200-year, respectively. R2DM is shown to be useful as a tool in predicting salmon egg loss in gravel bed rivers.