源保護區治理因其關乎著多目標使用、公共利益、以及民眾權益問題，故常面臨沒有人願意為公共利益而犧牲之窘境，然水源保護區不同的利害關係人對於水資源有著不同的偏好，如何建立整合個人偏好成為社會偏好的社會選擇機制，使得水源保護區治理可以兼顧多元價值並符合民主程序，將成為本文主要探討的重點。本研究試圖以水源保護區範圍劃定為例，探討水源保護區治理所面臨之困境，水源保護區治理應具備之理念，以及水源保護區應治理的方式，並以臺北水源特定區為個案研究，探討運用社會選擇機制治理水源保護區之可行性，分別以訪談或問卷進行實證研究。 本研究發現，目前台北水源特定區之範圍劃定，造成管理體系及制度之成本提高、囚犯困境、經濟外部性、治理正當性等問題，但各方利害關係人均認同社會選擇理念，來決策水源保護區之範圍劃定，但也均認為立法委員投票這樣的社會選擇機制，將無法解決水源保護區所面臨之困境。

Owing to multiple purposes and public interestsin protecting watershed areas, no individual would be willing to sacrifice himself/herself for public benefit. Different stakeholders in watershed protection areas have different preferences. How to establish mechanisms for integrating personal preferences to social preferences is the main issue of incorporating multiple values in a democratic procedure for protecting watershed areas. The current paper depicts the difficulties in governing Taipei Water Source Domain. Based on the results of questionnaires, the paper makes recommendations as to how watershed protection areas should be governed. The results show that high transaction costs, prisoner’s dilemma, externality, governance legitimization are common issues in the delineation of the Taipei Water Source Domain. Different stakeholders have agreed to use social choice mechanisms for delineating watershed protection areas, but have opposed to entrust legislators to vote on their behalf.