洪水風險交易制度之建構與分析

RISK TRADING IN FLOODMANAGEMENT

為降低複雜的地理和經濟條件所構成的訊息成本、善用地方資源及知識，並分攤中央治洪的財政負擔， 本文提倡以洪水風險交易制度（tradeable flood permits） 作為一個符合成本有效性分析（cost-effectiveness analysis）和分權式管理之工具。本文之貢獻在於改進洪水風險交易制度的理論模型， 並加強闡釋制度之設計。首先以排放權交易市場模型為基礎，融合各區自然與人文條件所影響的入滲能量和所希望承受的風險程度等限制，進而納入土地開發、自然防災法， 和傳統防災工法等決策變數。再者， 除援用並調整既有之發展權交易（transferable development rights） 外， 另研擬防災措施交易和風險中立化交易等兩種制度型態，以配合不同的制度條件和需求。

This paper improves the theoretical model that presents the importance of applying tradeable flood permits (TFPs) for efficiency improvement in flood management and the designs of the tradeable flood permits, based on Chang (2005). Land use patterns, and soft and hard engineering measures for flood management are the choice variables. Three types of TFPs are developed under three sets of institutional conditions accordingly. The TFP systemis virtually untried. It aims at compensating instead of substituting for the current planning system.