Assessing pollutant load emission from combined sewer overflows based on monitored changes of water levels and electric conductivity at overflow chambers

2017 Fiscal Year Final Research Report

• Project/Area Number: 16K14329
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Civil and environmental engineering
• Research Institution: The University of Tokyo
• Principal Investigator: Furumai Hiroaki 東京大学, 大学院工学系研究科(工学部), 教授 (40173546)
• Co-Investigator(Kenkyū-buntansha): 春日 郁朗 東京大学, 大学院工学系研究科(工学部), 准教授 (20431794)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Keywords: 環境質定量化・予測 / 連続モニタリン / 雨天時汚濁 / 合流式下水道 / 電気伝導度

Outline of Final Research Achievements

Accumulation and transport of in sewer sediments was studied using a distributed sewerage model to evaluate the occurrence and the behavior of combined sewer overflow (CSO) loads. It was found that there is a large spatial variation in the amount of sediment deposited during dry weather and transported during wet weather. It indicated that spatial distribution characteristics of sediment accumulation and transport should be considered in a sewer network in order to identify the significant sources of the CSO loads.
Occurrence of CSO loads was evaluated by monitoring water level, water temperature and electric conductivity in combined sewers. It was possible to judge the occurrence of overflow to storm water storage facility for flood control based on the relationship between water level and rainfall intensity. EC monitoring data can be used to evaluate dilution level of wet weather wastewater and estimate the contribution of first flash on the pollutant load in combined sewer pipes.

Free Research Field

水環境保全・制御