An Optimal Design Model for New Water Distribution Networks in Kigali City

Abstract

This paper is concerned with the problem of optimizing the distribution of water in Kigali City at a minimum cost. The mathematical formulation is a Linear Programming Problem (LPP) which involves the design of a new network of water distribution considering the cost in the form of unit price of pipes, the hydraulic gradient and the loss of pressure. The objective function minimizes the cost of the network which is computed as the sum of the initial cost of the individual pipes. The model is solved using the Simplex algorithm which is implemented by the Linear Interactive and Discrete Optimizer (LINDO) using data from a sample network in Kigali. The optimal solutions show that the cost is reduced compared to the cost of the sampled existing networks of Kigali city.

Keywords: Linear Programming models, water distribution network, hydraulic gradient, pressure loss, minimize cost, Kigali City

Rwanda Journal, Volume 23 Series C, 2011