Modernization of stormwater runoff analysis of urban drainage

合流污水溢流问题的治理日益严重，是目前合流污水治理的迫切需要。为了解决CSO问题，本研究在长冈市联合下水道系统区域的观测棚内设置了自动采样器、流量计和雨量计，并对关堂町下水道出水口的CSO进行了20多个月的连续观测。此外，还利用降雨径流模拟模型之一MOUSE进行了降雨径流模拟。通过仿真得到了与实测值相近的数值。通过观测和计算，揭示了径流质量和径流数量等径流行为。建立了能使CSO污染负荷减半的储罐尺寸。

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. 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.