在2006年1月，立法院通過了總金額合計高達1,410億《水患治理特別條例》、《石門及其集水區整治特別條例》。本文以許多民間環保團體為監督治水預算成立的1410大禹治水聯盟為研究個案。藉由政治機會結構理論來說明支持與推動治水預算的「利益聯盟」（行政院、水利機關、立法委員與地方政府）是如何形成？為何結盟？如何相互合作讓本案順利通過？並分析在立法院審查中治水聯盟（環保團體、社大、立法委員）是如何透過政治機會結構連結？如何運作？治水聯盟又是如何利用各種政治機會以累積實力與監督政策？研究發現在地方壓力下，主張審慎監督的治水聯盟其實不易著力。一方面因議題範圍實在太大，無法動員特定地區的利益相關者；另一方面也是利益鐵三角聯盟內的同盟關係非常穩固。故治水聯盟只能藉製造社會壓力與少數友好立委的協助，在立法過程中爭取加入更多資訊公開、績效評估與公民參與機制。以透過這些新增的政治機會，在後續政策執行階段中找出更多公共參與和監督的著力點。

In January 2006, the Legislative Yuan passed the “Special Act for Flood Control” and the “Special Act Governing the Management of the Shimen Reservoir and its Catchment Area,” all amounting to NT1 billion. This essay examines the case of the 1410 Ta-Yu Flood Management Alliance, formed by many environmental organizations for the purpose of supervising the budget legislation. By using political opportunity structure theory, this essay gives an account of how the alliance of interests (formed by the Executive Yuan, the Water Resources Agency, legislators and local governments) is organized and how they cooperate. Furthermore, this essay asks how the environmental alliance uses different kinds of political opportunities in order to supervise the policy. This research discovers that in the face of the alliance’s proposition of prudent supervision, it is not easy to uphold this under local pressure. On one hand is the alliance’s inability to mobilize related stakeholders in specific areas due to overreaching issues and on the other hand is the solid relationship within the interest alliance. It is only through a few friendly legislators and social pressure that a few regular mechanisms have been added for the increased disclosure of information, performance evaluation and citizen participation during the legislation process. Through these new political opportunities, it is hoped that a stronger foothold for public involvement and supervision can be found in the policy implementation stage.