摘要： 水资源法律地位的确立是罗马法制定水法制度的出发点，以公水和私水的划分为据，以民事权利为中心和以行政授权为中心的两套不同的水资源调整模式在罗马法时期已现雏形。19世纪末期以后，围绕公水、私水的基本分类而建立的传统水权法律制度也向现代水权转变。传统水权的调整规范主要是私法规范，其调整模式主要表现为水资源利用为中心的民事权利义务模式。行政水权、法定水役权以及可交易水权是以制定法形式存在的现代水权的典型形式。作为实现水资源可持续综合管理的一种法律手段而提出的可交易水权不同于完全自由水市场背景下的可交易水权，构建可交易水权所面临的最大挑战性问题在于：可交易水权如何能够在随着水文、气候变化而灵活调整的同时仍然满足稳定性、安全性等交易特性，这同时也是构造可交易水权制度的重中之重。

关键词: 公水 , 私水 , 传统水权 , 现代水权 , 可交易水权

Abstract: The nature of water resources was the first step for Roman’s water rights system．Two different ways of defining public water and private water has marked the distinction of two different water resources distribution model since the time of Roman law；one concentrating on civil rights while the other focusing on discretionary powers．Traditional water rights，which are structured according to basic classifications between public waters and private waters，has been evolving towards contemporary water rights since late nineteenth century．The rules of the traditional water rights took the form of a set of Rights，duties and liabilities，concentrating on water resources use．Discretionary water rights，statutory usufructuary rights and tradable water rights are three typical models of contemporary water rights in statutory regimes．Tradable water rights，as a legal instrunent of sustainable water resource management，are different from those under entirely free water markets．The biggest challenge facing the proposed tradable water is：how can it be flexible to changes in climate，and still satisfy stability，safety and other features of trading．This is also the main focus point in constructing tradable water rights legal structure．

Key words: Public water, Private water, Traditional water fights, Contemporary water rights, Tradable water rights