徵收水污染防治費對河川水質之影響

Abstract

國內對於水污染防治係採用「行政管制」與「污染排放費」並行之政策，「水污染防治費」正是在社會總成本達最低之情況下，達成河川水質目標所採用之經濟誘因政策。本研究以南崁溪流域為研究範圍，針對事業水污染防治成本分析，評估徵收水污染防治費對河川水質之影響，利用QUAL2K河川水質模式，模擬定常態(Steady State)下樹枝狀混合均勻之河川水質，以評估在不同水污染防治費徵收費率下，對於河川水質之改善效益及預估徵收水污染防治費的實施成效。 研究結果顯示隨水污染防治費費率的調高，污染減量呈現增加之趨勢，且水質可獲得改善。在低流量(Q75)設計下，當水污費費率訂為70元/公斤COD時，BOD濃度可降低至4.00mg/L，使水質符合南崁溪之水體分類水質標準。在枯流量(Q90)設計下，當水污費費率調高至40元/公斤COD時，則可使BOD濃度降低至符合南崁溪之水體分類水質標準。

In Taiwan, the policy to prevent water pollution is adopting “administrational control” and “effluent charge”. The effluent charge is an economic incentive policy for achieving the required stream water quality goals under the minimum total social cost. This study analyzed the water pollution prevention cost of undertaking in the Nan-Kan River basin. By using the QUAL2K stream water quality model to simulate well mixed water quality on steady state, we can evaluate the improvement of stream water quality and effects of effluent charge levying under different effluent charge. The result shows the pollution-reduction increases and stream water quality improves when the effluent charge is going up. As the effluent charge is 70 NT/Kg-COD, the BOD can reduce to 4.00 mg/L and conform to the stream water quality of Nan-Kan River basin, under the designed stream flow is Q75. Under Q90, as the effluent charge is 40 NT/Kg-COD, the BOD can reduce to 3.99 mg/L and conform to the stream water quality of Nan-Kan River basin.