an application in Ho Chi Minh City - Vietnam Nguyen Van Quoc creator Nguyen Luong Bach Chairperson Fujiwara, Okitsugu Examination committee Ha, Sung Ryong Examination committee Government of Japan Scholarship donor text series technical report th Bangkok Asian Institute of Technology 1999 continuing eng 51 leaves Newly developed areas need new water supply systems. A new system is usually connected to the existing system for improving its supply capacities. The main objectives of the new system design are the maximum water supply capacities of the whole system including old and new network with the minimum exchange flow for available demand pattern. In this study, a basic model including hydraulic simulation, cost design such as pipe capital, operation cost and pump investment is modified from previous works and further developed. The so-called optimal or minimum cost design of water distribution systems has been approached. This model can be used to design completely new water systems. However, for the water system expansion problem this model has some disadvantages. Therefore, a revised model is proposed to solve this problem. These models are applied for extending water system in Ho Chi Minh City of Vietnam. The existing system has capacity of 600,000 m3 Id. Its distribution network consists of 574,000m of pipelines ND150 to ND 2000mm that still service 243,500 of customer connections. The new system requires capacity of 300,000m3 /day with one more water source, two booster stations and about 100,000m of primary pipelines connected to the existing system. The primary network of the whole system includes 31 nodes, 43 links, 2 water sources and 3 booster stations. The model is solved by setting up a computer program with 95 variables, 244 bound conditions, 86 linear and 62 nonlinear constraints. The reasonable results of computer program running for design extending water supply system in HCMC have proved the applicability of the developed models. A thesis submitted in partial fulfillment of the requirement for the degree of Master of Engineering, School of Civil Engineering Thesis (M.Eng.) - Asian Institute of Technology, 1999 Water Distribution Water-supply engineering Vietnam Ho Chi Minh Asian Institute of Technology. http://203.159.5.9/ait-thesis/detail.php?q=B12349 http://203.159.5.9/ait-thesis/detail.php?q=B12349 211099 20260818170729.0