2013 Volume 19 Pages 93-98
The overall history of repairs of the Ohkouzu Diversion Channel which had been constructed in 1924 to bypass the Shinano River flood to the Sea of Japan is investigated by a large number of valuable data of the past flood control works. Thorough examination of constructions for preserving riverbed stabilization as well as analyses of data achieved from both survey and hydrological and geological investigations over the past 80 years leads to the conclusion that riverbed preservative groundsills have played a great role in riverbed stabilization of the Channel. Investigation reveals that use of blocks and fascine mattresses was quite effective in preventing partial erosion of riverbed preservative groundsills. Moreover, it was found that the Second Consolidation dam and blocks set after the building of baffle pier were greatly successful in keeping up the function of the channel structures and in preventing the change in channel bed.
