結合HSPF模式與負荷延時曲線法推估北勢溪集水區變動的總量管制值

Combining HSPF model and Load Duration Curve (LDC) method for developing variable Total Maximum Daily Load (TMDL) in PeiShi creek watershed

陳憲琦(Hsien-Chi Chen)

指導教授 ： 林鎮洋

國立臺北科技大學/工程學院/土木與防災研究所/碩士(2011年)

https://doi.org/10.6841/NTUT.2011.00689

摘要

十多年來許多研究使用HSPF（Hydrological Simulation Program Fortran）模擬北勢溪集水區之非點源污染，但每年水文條件不同，使得每年推估的總量管制值不盡相同，造成實務上施行總量管制之困擾。另一方面，傳統總量管制方法中，常採用低流量（如Q75）為設計條件，此方法對於點源污染為主之區域尚稱合適，然而對於非點源為主之區域，如本研究之北勢溪集水區，則可能過於嚴苛。因此，若能根據不同流量狀態有不同總量管制值，這樣可以最經濟的方式進行水質管理。
本研究考慮非點源污染受時間及河川流量的變化影響，故利用時間序列模式HSPF結合負荷延時曲線法（Load Duration Curve Method，LDC）推估北勢溪可變動的總量管制值。本研究結果顯示，結合HSPF與LDC法（簡稱HLDC法）評估各流況總磷削減負荷分別為高流量區間40.36 kg/day（30.46 %）、濕流量區間33.36 kg/day（56.70 %），總共需削減年總磷負荷5123 kg/yr；若以傳統設計流量Q75法，年總磷削減負荷達10566 kg/yr，超出HLDC法削減量5443kg/yr（+100.62%）。因此在同樣能達成水質目標的條件下，本研究所採用變動總量管制方法確實較為經濟實用。所以，受非點源污染為主之區域，如本研究之北勢溪集水區，較適合採用本研究之HLDC法發展總量管制。最後，因HLDC法及Q75法都以濕流量區間需進行總磷負荷削減最大，其總磷年削減負荷所佔比例分別為72 %、54 %，因此，受非點源污染嚴重之集水區，建議使用濕流量區間中點Q25作為非點源污染管理之設計流量。

關鍵字

負荷延時曲線 ； 總量管制 ； HSPF ； LDC ； HLDC ； TMDL ； Q75 ； Q25

並列摘要

Over the past decade, the HSPF model had been used to estimate non-point source pollution of the PeiShi Creek Watershed. However, those pollution estimates and the respective load reduction scenarios were different due to different hydrological conditions. Moreover, the traditional TMDL strategy, based on low flow condition (Q75), is thought to be conservative for area abounded with non-pont source pollution like the studied watershed. Thus, the present research combined HSPF (Hydrological Simulation Program Fortran) model and Load Duration Curve (LDC) method to estimate pollution loads and develop control strategy for different flow conditions for the PeiShi creek watershed. The purpose of this methodology is to control the pollution loads based on different flow regimes developed by the flow frequency analysis.
　　The results showed that total phosphorus load reduction for high flow range and middle flow range were 40.36 kg/day (30.46 %) and 33.36 kg / day (56.70 %) respectively and total phosphorus loads need to be reduced was 5123 kg/yr. On the other hand, the load reduction estimated by the traditional Q75 control strategy was 10566 kg / yr which is 5443 kg / yr (+100.62%) more than that estimated by the present research. Therefore, the present methodology, combining the HSPF model and LDC method, is thought to be much economical in designing TMDL control scenarios than the traditional Q75 method for area abounded with non-point source pollution like the PeiShi creek watershed. However, the Q75 method is still suitable for area with mainly point source load. Finally, this study suggests that using the middle flow range of Q25 as a non-point source pollution management of the design flow.

並列關鍵字

Load duration curve ； HSPF ； LDC ； HLDC ； TMDL ； Total Maximum Daily Load ； Q75 ； Q25

參考文獻

美國環境保護署網站（2011），http://www.epa.gov。

林慧儒（2008），魚逮魚堀溪非點源污染量之推估，碩士論文，臺北科技大學土木與防災研究所，臺北。

施禹州（2007），河川污染負荷量之推估─以北勢溪為例，碩士論文，國立臺灣大學土木工程學研究所，臺北。

Yu, S. L., Hamilton, P. A. and Kent, C. E. (1984). ‘‘Temporal distribution of rainfall in Virginia.’’ Final Rep. VTRC 85-R29, Virginia Transportation Research Council, Charlottesville, Va.

Bonta, J. V. and Cleland, B. (2003).〝Incorporating natural variability, uncertainty, and risk into water quality evaluations using duration curves,〞Journal of the American Water Resources Association, 39 (6), pp. 1481-1496.