Optimal estimation of DO, BOD, and stream parameters using a dynamic discrete time model

A modified Streeter‐Phelps equation is used as the starting equation to obtain a discrete time mathematical representation which represents a model for the biological oxygen demand and the dissolved oxygen concentrations in a polluted stream. The unknown parameters to be estimated are treated as state variables in order to compute their numerical values from noise‐corrupted measurements. An optimal estimator is constructed for the estimation of the unknown parameters. The optimization scheme can be implemented in a small computer. The approach is illustrated by a numerical example.