近年政府為解決台灣水患問題，透過「易淹水地區水患治理計畫(2006年至2013年)」及「流域綜合治理計畫(2014年至2019年)」之執行，陸續完成數十座區域排水滯洪池工程，其成效是否與計畫所預期之結果相符，確有追蹤與探討之必要。本研究採用雨量資料及水位觀測資料，用以瞭解滯洪池於不同降雨等級事件所發揮之效益，評估滯洪池是否達到「欲消減之峰值」及滿足「足夠之滯洪體積」兩大目標。
本研究研擬一套系統化資料蒐集為基礎，將滯洪池規劃、設計至完工監測等資料進行分析與評估之滯洪池成效評估流程，包括資料蒐集、目標達成度評估、借鏡學習度評估。目標達成度為滯洪池工程之預期目標之達成程度，其評估結果可反映滯洪池設置後之成效。借鏡學習度為相關記錄資料及觀測資料完整性之評估，其評估結果可反映滯洪池資料不足處，以利增補資料之參考，亦可作為其他滯洪池案例規劃設計之參考
本研究以仁德滯洪池為案例，先蒐集滯洪池相關資料，並針對成功標準(Success Criteria)、基本資料蒐集(Baseline Survey)、設計理念文件(Design Rationale Documents)、設計書圖(Design Drawings)、完工初期調查(As-built Surveys)、監測計畫(Monitoring Program)等六個項目加以分類及釐清。
透過案例研究，北池計畫目標達成度評估結果為61.54%，南池計畫目標達成度評估結果為53.85%，顯示仁德滯洪池於計畫目標達成狀況良好。另經由系統性資料蒐集及歸類，仁德滯洪池整體評估之總分為53分，其借鏡學習度為59%，屬於良級。代表相關資料較齊全且對於未來其他滯洪池設計具有參考價值。

SUMMARY

There are more and more detention ponds set in recent years. What is their effectiveness and how to evaluate? This study developed an assessment method to evaluate the effectiveness of detention ponds,which structured by documents collection, degree of objective achievement, and degree of learing. In order to develop the method, this study collected the case of Rende detention pond to study their functions of the dention effectiveness. It showed that the funtion of detention basin was realized while the water stage changed obviously. Furthermore, this study combined water stage data and storge volume relationship to obtain the storage volume during storm events, and calculated the net flow through the storage volume differential to estimate whether the objective achieved or not.In the most of the events, the storage volume percentage of the Southern pond is higher than the one of the Northern pond. The results show that the Rende pond is in a good state of the effectiveness.Otherwise,the degreed of learing opportunity is 59% by evalution of the document collection.It means that the Rende pond can be learned by other detention basin for planning and designing. Ultimately,it also shows that the method in this study is suitable for evaluation of detention effectiveness.
Key words: detention ponds, effectiveness, objective achievement, learning opportunity

INTRODUCTION

One of the major tasks in stormwter manage is to reduce peak flows after the development. Astormwater drainage system consists of conveyance and storage facilities. Detention and retention ponds are the major storage facilities designed for stormwater quantity and quality controls. Storage facilities in a dranage networks should be placed at the strategic locations in order to effectively attenuate peak flood flows. Urbanization results in more impervious areas. Reduction in soil intiltration leads to the increases in runoff volumes and peakflows. Pavements allow stormwater to move faster and to become more concentrated. There are more and more detention ponds set in recent years. What is their effectiveness and how to evaluate? This study developed an assessment method to evaluate the effectiveness of detention ponds, which structured by documents collection, degree of objective achievement, and degree of learing. In order to develop the method, this study collected the case of Rende detention pond to study their functions of the dention effectiveness.

MATERIALS AND METHODS

This study developed the evalution method which was involved document collection, degreed of objective achievement and degreed of learning. In this study, we modified the document collection structure into six components, which are objectives and achievement criteria, baseline survey, design rational, design drawings, as-buil survey, post-project monitoring surveys. Degreed of objective achievement analysis process included rainfall analysis, water stage analysis, storage volume analysis and net-flow of detention analysis. This study collected hourly rainfall data obtained Rende, Mamiao, and Yongkang precipitation gages from 2014 to 2016, and sort storm event by grade which was provide by Central Weather Bureau.It was needed to judge the rationality of water stage data. It could not be adopted if the water stage of the inflow channel was higher the one inside the detention pond. It showed that the funtion of detention basin was realized while the water stage changed obviously. Furthermore, this study combined water stage data and storge volume relationship to obtain the storage volume during storm events, and calculated the net flow through the storage volume differential to estimate whether the objective achieved or not.
This study applied the method to evaluate the project-Rende detention pond, which comprised the northern pond and the southern pond. The northearn pond was designed to collect the runoff volumes of the watershed of the Tukuzai drainage, and the southern one was designed to collect the runoff volumes of the upstream watershed of the San-Yei-Chi drainage converged by Rende drainage.

RESULTS AND DISCUSSION

Since that it was not rational that the water stage in the Tukuzai drainage inflow channel was higher the one inside the detention pond, the water stage data in 2014 could not be adopted.(shown in Figure. 1) The storage volume percentage results of the Northern pond and the Southern pond shows in Figure. 2.In the most of the events, the storage volume percentage of the Southern pond is higher than the one of the Northern pond. The degree of objective achievement result shows in Figure. 3.The degreed of objective achievement of the Northern pond is 64.54% and the one of the Southern pond is 53.85% in average during the 2 year(2015 & 2016).Otherwise,the degreed of learing opportunity is 59% by evalution of the document collection.

CONCLUSION

The degreed of objective achievement of the Northern pond is 64.54% and the one of the Southern pond is 53.85% in average during the 2 year(2015 & 2016).It shows that the Rende pond is in a good state of the effectiveness.Otherwise,the degreed of learing opportunity is 59% by evalution of the document collection.It means that the Rende pond can be learned by other detention basin for planning and designing. Ultimately,it also shows that the method in this study is suitable for evaluation of detention effectiveness.

1. Ab Ghani, A., Zakaria, N., & Ainan, A. (2008). Sustainable Urban Drainage System (SUDS)–Malaysian Experiences.
2. Australia(IPWEA), I. o. P. W. E. (2013). Queensland Urban Drainage Manual.
3. Bloomberg, M. R., & Strickland, C. (2012). Guidelines for the Design and Construction of Stormwater Management Systems. New York City Department of Environmental Protection, in consultation with the New York City Department of Buildings, New York, NY, USA.
4. Brown, S., Stein, S., & Warner, J. (1996). Urban drainage design manual.
5. Coombes, P. J., Frost, A., Kuczera, G., O'Loughlin, G., & Lees, S. (2002). Rainwater tank options for stormwater management in the upper Parramatta River Catchment. Paper presented at the Water Challenge: Balancing the Risks: Hydrology and Water Resources Symposium 2002.
6. County, K. (1998). King County, Washington surface water design manual: The Department.
7. David, L., Carvalho, R., Isidro, R., & Sobral, M. (2011). Stormwater control of new urban developments–Planning and modelling the Penalva system.
8. Dhalla, S., & Zimmer, C. (2010). Low Impact Development Stormwater Management Planning and Design Guide. Stormwater Guide. Toronto: Toronto and Region Conservation Authority.
9. Downs, P. W., & Kondolf, G. M. (2002). Post-project appraisals in adaptive management of river channel restoration. Environmental Management, 29(4), 477-496.
10. Guo, J. C. (1999). Detention basin sizing for small urban catchments. ASCE J. of Water Resources Planning and Management, 125(6), 380-382.
11. Scraggs, C., & Lemckert, C. J. (2004). Preliminary Estimation Methods for Sizing Detention Basins in Queensland. 0.
12. Tompkins, M. R., & Kondolf, G. (2007). Systematic postproject appraisals to maximize lessons learned from river restoration projects: case study of compound channel restoration projects in northern California. Restoration Ecology, 15(3), 524-537.
13. 巨廷工程顧問股份有限公司（2009），沿海地陷區蓄洪設施水資源之應用研究，經濟部水利署水利規劃試驗所。
14. 巨廷工程顧問股份有限公司（2014），都會區排水系統與滯蓄洪設施連結之研究，經濟部水利署水利規劃試譣所。
15. 白櫻芳（2016），建築技術規則雨水貯集滯洪設施減洪效益評估與法令探討研究，內政部建築研究所。
16. 吳雅雯（2013），河相觀點之河川復育成效評估，成功大學水利及海洋工程學系學位論文。
17. 吳瑞賢（2002），滯留設施之規劃與設計(III)最佳化佈置與總量管制設計。
18. 沈世琨、林文松、張仁德、林茂佟、胡湘帆（2004），區域性排水防洪預警系統應用探討，中華技術電子書， 62，頁 108-122。
19. 禹安工程顧問股份有限公司（2010），美濃地區設置滯洪池可行性評估，經濟部水利署第七河川局。
20. 財團法人中興土木科技發展文教基金會（2013），農業區滯洪效果評估及對區域排水設計流量影響之研究，經濟部水利署水利規劃試譣所。
21. 財團法人台灣水利環境科技研究發展教育基金會（2006），滯洪設施模式分析評估與規劃設計標準作業程序之研究(2/2)，經濟部水利署水利規劃試驗所。
22. 財團法人台灣水利環境科技研究發展教育基金會（2012），滯洪池之功能檢討與管理評估，經濟部水利署水利規劃試驗所。
23. 財團法人成大研究發展基金會（2004），綜合治水與滯洪設施整合利用研究，經濟部水利署水利規劃試驗所。
24. 財團法人國家實驗研究院台灣颱風洪水研究中心（2014），國家級防災監測及模式測試基地建置，經濟部水利署水利規劃試驗所。
25. 財團法人國家實驗研究院台灣颱風洪水研究中心（2015），典寶溪及宜蘭河防災測試基地監測及加值應用研究，經濟部水利署水利規劃試驗所。
26. 財團法人國家實驗研究院台灣颱風洪水研究中心（2016），105年典寶溪及宜蘭河防災監測及模式測試基地觀測，經濟部水利署水利規劃試驗所。
27. 財團法人農業工程研究中心（2013），區域排水滯蓄洪區劃設與補償措施研擬之研究，經濟部水利署水利規劃試譣所。
28. 國立成功大學（2016），運用閒置公有(營)土地做為滯洪設施之研究，經濟部水利署水利規劃試譣所。
29. 國立臺灣大學（2013），滯洪池之濕地生態功能評價及改善研究，經濟部水利署水利規劃試譣所。
30. 國立臺灣大學水工試驗所（2011），國家級防災監測及模式測試基地建置規劃，經濟部水利署。
31. 陳正炎（2004），滯洪設施之設計研究 (四)。
32. 黃中信（2007），三爺溪流域綜合治水建置合適滯洪池設施之效益評析，成功大學水利及海洋工程學系碩士在職專班學位論文。
33. 經濟部水利署（2010），三爺溪排水及西機場排水治理計畫。
34. 經濟部水利署水利規劃試驗所（2006a），河川治理及環境營造規劃參考手冊，經濟部水利署水利規劃試驗所。
35. 經濟部水利署水利規劃試驗所（2006b），區域排水整治及環境營造規劃參考手冊。
36. 經濟部水利署水利規劃試驗所（2006c），滯洪設施規劃設計參考手冊，。
37. 經濟部水利署第六河川局（2008），三爺溪排水系統整治及環境營造規劃報告。
38. 葉正傑（2015），典寶滯洪池對岡山地區之整體效益分析，。
39. 劉永得、陳意文（2012），台南科學工業園區 (二期基地) 滯洪池設計及操作管理探討，中興工程（117），頁 65-72。
40. 蔡亦睿（2016），連續降雨歷程對滯洪池效益影響之研究，成功大學水利及海洋工程學系學位論文。
41. 蘇郁文（2016），河溪復育整治計畫目標達成度與借鏡學習度之評估研究-以台灣溪流為例，成功大學水利及海洋工程學系學位論文。