越流堤天端への可動堰設置による氾濫抑制効果の検討ー菅生・稲戸井・田中調節池を対象として一

抄録

The detention reservoirs are one of the most effective countermeasures to prevent the flood damage. They are normally constructed with an overflow levee, but if a movable weir is constructed on that and an artificial operation is done, some additional effects are expected. As one example, saving the capacity of reservoir, when a flood that brings inundation exceeding the river flowing capacity, the damage may be avoided or reduced. In this paper, 3 detention reservoirs located in the middle Tone River were chosen as the examination object, then scenarios that an inundation has occurred in Toride and Abiko city which is located in the lower of the reservoirs were assumed and possibilities of the damage reduction with a movable weir on the overflow levees were simulated by using numerical model. Then some valuable results which might be able to reduce the damage of the inundation were obtained. For instance, decrease of the inundated area and average or maximum water depth compared to cases without movable weir is that. Additionally, compulsory drainage operation from river to reservoirs with inundation monitoring was examined.