SIMULATION ANALYSIS FOR POLLUTANT RUNOFF MANAGEMENT USING A STORMWATER RETENTION POND

This study aims at examining an availability of stormwater retention for pollutant runoff management and showing useful knowledge through simulations based upon monitoring data. A facility selected is a stormwater retention pond which is included in Moriyama River Water Treatment Facility located at Southern Lake Biwa basin. It has been operated in order to improve water quality which runs off into Lake Biwa by a series of facilities of a pre-treatment facility, a stormwater retention pond and a vegetation pond. Authors have monitored water quantity and quality into/out of the retention pond during storm events for four years, and developed a simulation model from the surveyed data. As a result of discussion on simulation results using the model, it was shown that stormwater retention had enough possibility to control pollutant runoff during storm events if correct operation was done. It was also shown that the simulation model was available for examining an optimal operation of the stormwater retention pond. These findings would leads to better environmental management of pollutant runoff.