In the Showa Period, the practice of 'kawa-zawae (river dredging)' to remove sludge disappeared with the decline of Hachiman-bori's importance as a canal and resulted in sludge sedimentation on the canal bed and foul odor in the area.
昭和になると、運河の機能を失った堀は、汚泥を掬い上げる「川ざわえ」が廃れ、川底にヘドロが堆積し、悪臭を放つようになった。