Optimization of Integrated Urban Wet-Weather Control Strategies

An optimization method for urban wet-weather control (WWC) strategies is presented. The developed optimization model can be used to determine the most cost-effective strategies for the combination of centralized storage-release systems and distributed on-site WWC alternatives. The two major components of the model are an objective function that evaluates the cost of a given option and a process simulator that describes the production function. The data for developing the production function are generated by running process simulation models that provide estimates of performance for specified values of the inputs. In earlier research, a prespecified number of simulations were run and then an analytical function was fitted to the database. Typically, the fitted function did not approximate the data well, and manual graphical procedures or numerical analysis software had to be used to approximate the response surface. This paper presents a much improved version of this approach wherein an optimizer is used to direct the simulation process toward the optimal solution. Even more important, the results can be extended from three-dimensional problems to n-dimensional problems.