水污染整治決策模型之研究-以淡水河為例

Abstract

河川水污染依照來源可分為生活污水、畜牧廢水、事業廢水以及非點源污染等四大類型，面對生活污水為主要污染來源的河川水污染整治，最有效的策略為推動污水下水道建設。但在污水下水道系統未完成建設前，仍有部分區域之生活污水未經處理而直接排放到河川中，因此對於都會區河川水污染整治的策略，除了持續興建污水下水道之外，亦應考慮建設期間的水污染整治。

本研究透過建立生活污水至河川的關聯，並且結合將優選模式及水質模式，發展水污染整治決策模型，並且利用田口法求解優選模式，該模型除了可以求解水污染整治的最佳策略及對應的河川水質外，亦可指出目前水污染整治的關鍵地區。本研究以淡水河流域為研究的區域，在101年的操作策略下，大漢溪中游為水質改善效益最顯著的流域；而新店溪以及基隆河於本研究模擬結果顯示水質改善效益不大。 將決策模型用於以106年為目標的情境分析，顯示大漢溪的污水處理設施對於淡水河水質改善的成效依舊是最大，但基隆河、淡水河本流以及新店溪的污水處理設施開啟的數量亦大幅減少，隨著用戶接管率的提升，有越來越多的截流站的策略是不開啟。比較101年以及106年模擬結果，顯示若干截流站的操作策略皆為關閉，以基隆河、淡水河本流及新店溪的狀況較明顯，因此若是在系統量能沒有提升的狀況下，隨著用戶接管普及率的提升，未來會有更多的截流站採取關閉的策略。

River water pollution can be classified into four types according to the sources, which are domestic sewage, livestock wastewater, industrial wastewater, and non-point source pollution. To remedy the domestic sewage pollution, the most effective strategy is the construction of sewerage systems. Domestic sewage continues to be discharged without treatment before the entire system completely constructed. Therefore, besides building the sewerage system, the remediation strategy should also concern the water pollution treatment problem during the construction period.

This research develop a water pollution remediation decision support modelling through building a waste relationship, which is from house to river, and combining optimization method and water quality model, then integrating Taguchi method to solve the model. This model not only apply water quality under the optimal strategy, but also point out the key part of the system. This research applies the model to Tamsui River basin, under the condition of 2012, take Dahan River as example, the severely polluted length was 18 Km, the rest was moderately polluted or better. Under the optimal strategy, Dahan River water quality is the greatest improvement in the Tamsui River Basin, water quality in Xindian Creek and Keelung River is not as well as Dahan River.

Applying the model in 2018, the result shows that Dahan River water quality is stilll the greatest improvement in the Tamsui River Basin, but more and more interception stations are closed in Xindian Creek and Keelung River as the household connection rate raise. Compare the result in 2012 and 2018, it shows that some interception stations are closed, which happened frequently in Keelung River, Xindian Creek and Dansui River, so as the household connection rate raise, more and more interceptions will be closed.