Estimating the effect of wastewater treatment facility’s operating failure due to disaster on river’s water quality

Abstract

The study investigated a disaster countermeasure system for wastewater treatment facilities, focusing on both structural and non-structural responses. As part of the non-structural countermeasures, the effect of untreated effluent from damaged wastewater treatment facilities due to disasters on the river was simulated. The results showed that untreated effluent from the wastewater treatment facility did not affect the river's water quality due to its low flowrate. However, it had a significant impact on the water quality of the river when the flowrate of untreated effluent had increased. The study also evaluated the efficiency of movable treatment units as part of structural countermeasures to respond to damaged wastewater treatment facilities. The researchers simulated the effect of effluent treated by movable treatment units on the river. The findings indicated that movable treatment units were effective in reducing the impact on the river's water quality for small-scale wastewater treatment facilities. However, for mid and large-scale wastewater treatment facilities, disaster countermeasures should prioritize ensuring sufficient storage space for untreated water rather than relying on other emergency response devices, such as movable treatment units tested in this study, to respond to disasters.