Keisuke OHBASAWA

Evaluation of CSO system control of Nagaoka City by stormwater runoff simulation model based on long term continuous observation

Shoichi FUJITA �CToshiya KOMATSU �CShuji HIMENO

Solution of combined sewer overflow (CSO) problem is getting serious, and the improvement works are pressing needs recently.
In this study, to solve the CSO problem, an automatic sampler, flow meters, and a rain gauge were set up at the observation hut in the combined sewer system area in Nagaoka, and CSO of Kantomachi sewer outlet was continuously observed more than 20 months. In addition, stormwater runoff simulation was carried out using the MOUSE, one of the stormwater runoff simulation models. In addition, stormwater runoff simulation was carried out using the MOUSE, one of the stormwater runoff simulation models.
As a result, similar values as the measurement values were obtained by the simulation.
Runoff behavior including runoff quality and quantity was illuminated through observation and calculation. The dimensioning of a storage tank to reduce the CSO pollution load by half was established.