TRIAL FOR COMPREHENSIVE ESTIMATION FROM THE VIEWPOINT OF FLOOD CONTROL AND ENVIRONMENT BASED ON FORECAST ON CHANGE OF RIVER AFTER RIVER IMPROVEMENT IN SEGMENT 2

Abstract

In segment-2 river, when low-water channel is widened, sometimes, sediment piles up, plants grow there and deposit fme sediment, and low-water channel narrows as a result. We developed 2-dimension river bed variation analysis model that can simulate these phenomenon and applied this model in Ongagawa River. With this model, we calculated the change of physical environment and vegetation after river improvement, tried to compare river improvement plans comprehensively from the view point of flood control and environment, and proposed the framework of monitoring and river management after river improvement.