Abstract:

Risk-informed decision making (RIDM) methods are increasingly used to assist in providing a means to support capital expenditure programs for hydropower schemes. Through the use of asset management tools and strategies, both regular maintenance, long-term rehabilitation of equipment and review of asset fitness for purpose can be considered across a portfolio of infrastructure. These tools provide decision-makers with desired metrics that enable more efficient use of capital through a risk informed process. These risk based tools allow an increased understanding of how concepts such as deferred maintenance or design & performance reviews may influence risk to all associated stakeholders.

Dam safety risk assessment processes primarily focus on life safety for decision-making. RIDM methods have been developed so that we can understand and compare various types of dam failure risks, many of which have an extremely low likelihood combined with very high consequences.

This paper will discuss the value of combining RIDM methodologies with risk based asset management programs. An example will be provided of how this was done for a portfolio of nine dams and nine power stations on the Waikato River in New Zealand. This hydropower chain is positioned on a single river which increases the complexity of understanding interdependent risks. The generalized process of determining annualized cost risk is described, and how the process provides insight into both the dam safety and asset management programs. A description of how potential dam safety related impacts (such as life safety, environmental, corporate and third party impacts) are integrated within the asset management program to increase the understanding of the relative risks of their portfolio of structures is given. An overview of lessons learned is provided to show the benefits of conducting this assessment.

Key words: hydropower portfolio, safety risk, risk-informed decision making

摘要： 风险知情决策制定方法正越来越多地被用于支持水电项目的资本支出计划。通过使用资产管理工具和策略，可以在整个基础设施组合中综合考虑设备的定期维护、长期修复和资产性能评估。这些工具为决策制定者提供了所需的度量标准，可以通过风险知情流程更有效地使用资本。这些基于风险的工具能让人更好地理解延迟维护或设计及性态评估等概念如何影响所有利益相关者的风险。
大坝安全风险评估过程主要关注决策制定的生命安全方面。风险知情决策制定方法的发展使决策者能够了解和比较各种类型的大坝失事风险，其中许多情况都只具有极低的失事可能性，但失事后果非常严重。
笔者将讨论风险知情决策制定方法与基于风险的资产管理计划相结合的价值。案例将说明其如何应用到新西兰怀卡托流域9座大坝和水电站的资产组合中。这些水电站位于一条独立的河流上，这加大了理解相互依存风险的复杂性。文章阐述了确定年化成本风险的一般过程，以及如何通过该过程加强对大坝安全和资产管理计划的理解；还阐述了如何将潜在的大坝安全相关影响（如生命安全、环境、企业和第三方的影响）整合到资产管理计划中，以增加对其结构物组合的相对风险的了解。文章概述了所获得的经验教训，以说明进行这种评估的益处。

关键词: 水电资产, 安全风险, 基于风险的决策