Uncertainty Analysis of Pollutant-Hydrograph Model in Assessing Inflow and Infiltration of Sanitary Sewer System

Abstract

Infiltration and inflow is a very severe problem in the sanitary sewer system. There are many method to evaluate the RDII, of which a novel conductivity-based method for estimating RDII was proposed. However, the reliability such as uncertainty and accuracy are seldom evaluated. In this paper, the uncertainties of model parameters were estimated using the generalized likelihood uncertainty estimation (GLUE) method. The parameter uncertainty was considered in three types of rainfall events and two different system characteristic. The proposed method exhibits distinct advantages, compared to the traditional flow-based methods, in estimating RDII and overflow particularly when the two processes happen simultaneously.