The confluence improvement project has greatly progressed in recent years, but the management accuracy of the quantitative control facility that is the base in the sewage management is low, possibly causing trouble in domestic sewer project coping with the social structural change and participation in overseas water business through utilization of stock.

 In this study, based on the hydraulic engineering theory and hydraulic experiments enabling sewage flow rate control with high accuracy, and the previous study aimed to make the theory into practical use on an extension of the knowledge of sewer standard books and field practices, the technical policy and so on in hydraulic design and facility structure design were embodied in the quantitative control facility important for the intercepting and combining flow rationalization and the combined sewer overflow (CSO) measure and so on still partially having problems even after the confluence improvement project.

 The sewer is operated while making full use of also advanced civil engineering and machine and electric technologies, but the base of effective utilization of the sewer system is the reliable sewage flow rate control, and effective achievement of the business purpose can be expected with higher transparency through the utilization of the control technique of this study.