The balance in the river system between sediment supply and flood flows produce this everchanging riparian ecosystem and the many microhabitats available to wildlife. The Russian River Enhancement Plan through extensive study of the hydrology, geomorphology, and riparian biology has documented the changes that modern development has brought to the river and the function of the riparian ecosystem. Two large reservoirs alter the hydrologic regime lowering the crest of floods but prolonging the release of floodflows long after the storm has passed. These prolonged flows saturate river banks increasing the likelihood of bank failure and adding to the instability of the system. The reservoirs are also the primary water supply for over 500,000 residents in three counties.
Water is released from the reservoirs down the river channel throughout the year.
Formerly the river dried up and a near surface groundwater aquifer supplied riparian forest and deep shaded pools were summer refuge to the salmon. The river now flows year round and is dominated by warm water fish species which prey on juvenile salmon and trout. The reservoirs also significantly reduce the sediment supply in the river causing the river to cannibalize its bed and banks. Following the reduction of flood peaks through construction of the dams, farmers were encouraged to reclaim the floodplains for agricultural use. The mature riparian forest was cut down and replaced by orchards and vineyards.