Sewer network design Optimization problem using ant Colony Optimization Algorithm and Tree Growing Algorithm

Abstract

This paper presents an adaptation of the Ant Colony Optimization Algorithm (ACOA) for the efficient layout and pipe size optimization of sewer network. ACOA has a unique feature namely incremental solution building mechanism which is used here for this problem. Layout and pipe size optimization of sewer network is a highly constrained Mixed-Integer Nonlinear Programming (MINLP) problem presenting a challenge even to the modern heuristic search methods. ACOA equipped with a Tree Growing Algorithm (TGA) is proposed in this paper for the simultaneous layout and pipe size determination of sewer networks. The TGA is used in an incremental manner to construct feasible tree-like layouts out of the base layout, while the ACOA is used to optimally determine the cover depths of the constructed layout. Proposed formulation is used to solve three test examples of different scales and the results are presented and compared with other existing methods. The results indicate the efficiency of the proposed method to optimally solve the problem of layout and size determination of sewer network.