污水下水道系統初期規劃設計之好壞，將嚴重影響其興建成本與未來的操作維護成本，而傳統規劃設計的工作係經由繁複的人力計算來完成，較缺乏工作效率與成本系統分析的精神。為節省規劃設計所需之人力與時間，並從無數的可行方案中找出一個真正的最佳方案{通常為符合設計規範的最低成本下水道系統過去一、二十年來已有不少的最佳化模式被發展出來並應用於實際的規劃與設計過程。
隨著最佳化技巧的演進，目前最佳化設計之模式己可較完整的以數學式子代表真實的系統，但仍無法為系統規劃人員所接受而使用。本研究運用一簡單且有效率的最佳化搜尋方法，界限隱式列舉法(Bounded Implicit Enumeration' BIE)' 發展一套可在個人電腦上執行的污水下水道系統設計最佳化程式(Sewer System Optimization program, SSOP) 。利用BIE 演算法尋找最佳方案之程序與傳統方法並無太大的差異，因此較容易為規劃設計人員所接受。SSOP 所需之記憶體甚少， 因此可以一般之個人電腦處理較大型的污水下水道系統。 The finding of a sewer system with the minimal capital cost and O&M cost is depended on the success of the prelimi nary design process. In practice, the selection of the size of pipes and the depth of excavation is performed with hand calculation and based on design engineer' s experience , which truely i s not an efficient and effective approach . In the past two decades, many optimization models had been developed to help in the design of gravity sewer system. The use of the opti mization mode l s , however , has been limited because of the complexity and flexibi Ii ty of the models. In thi s study, a simple and very effective algorithm, Bounded I mplicit Enumeration (BIE) , was used to develop an optimization model for sewer system design . The Sewer System Optimization Program (SSOP) uses the same approach as that used in practice design process to find the least cost system of a design problem. The r equirement of memory space of SSOP is very small as compared to other optimization models , thus it can be executed on a personal computer and used to solve a large s ewer system design roblem.
