but immediately before the implementation of the plan , furutaka was arrested by the shinsengumi (a group who guarded kyoto during the end of tokugawa shogunate ), and many of the people involved in the scheme were killed or arrested in what was known as the ikedaya incident . しかし、実行寸前で古高が新撰組に捕らえられ、計画に関与していた者の多くが池田屋事件で闘死、もしくは捕縛された。
although , in 1958 , they began the study of the implementation of the plan to roughly design specific types of dams and their capacities of water , they had to review the original flood control plan because the ise bay typhoon in the following year (1959 ) brought about considerable flooding , surpassing that of typhoon 13 , and furthermore , water demand grew tremendously due to the rapid growth of the population in the kansai area and the expanding hanshin industrial zone . 1958年（昭和33年）よりダムの具体的な型式や貯水容量等を検討する実施計画調査に入ったが、翌1959年（昭和34年）に伊勢湾台風が台風13号の洪水流量を超える水害を惹き起こした為洪水調節計画を再検討、更に関西圏の急激な人口増加と阪神工業地帯の拡充により水需要が逼迫。
