A Framework for Risk Analysis for Ecological Restoration Projects in the U.S. Army Corps of Engineers

Abstract

This report provides a framework for incorporating risk analysis into the six-step planning process for ecosystem restoration projects. This report is part of a larger research and development effort to develop procedures and guidelines for risk analysis in USACE ecosystem restoration planning. The focus is on risk analysis: identifying the range of possible outcomes from alternative ecosystem restoration actions, assessing the potential for achieving the desired outcome, characterizing the likelihood of adverse consequences, and communicating these findings to stakeholders and decision makers. This framework document makes simplifying assumptions to allow a focus on incorporating risk information in the planning and decision-making process. A conceptual model of the site and landscape is advocated as a central organizing structure within the six-step process for ecosystem restoration project planning. This is responsive to USACE directives that restoration projects be conceived in a systems context using an ecosystem and/or watershed approach. The conceptual model delineates the empirical quantities to be addressed in risk analysis and modeling. Although the planning process is described in six distinct steps, in practice these steps are iterative and often carried out simultaneously. Risk analysis within this context has the same character. The approach for incorporating risk analysis into themore » planning process provides direction intended to help the planner: • Identify the levels of uncertainty that are acceptable, at the start of the planning process. • Use conceptual and numerical models to communicate the planning team’s understanding of the ecosystem to others, and reduce the risk of mis-specifying the system. • Consider the uncertainty associated with the variables chosen to measure project effects. • Use alternative designs to manage identified uncertainty. • Use risk information to eliminate alternatives with unacceptable risk from consideration. • Incorporate risk analysis into the USACE four criteria of effectiveness, efficiency, completeness, and acceptability. • Use an alternative’s irreducible uncertainty as an attribute to be considered along with other attributes in the comparison of alternative plans. • Use risk information in the final plan selection process. There are three other efforts associated with this framework document, which offer information and guidance for incorporating risk analysis into cost-estimation, and biological and hydrologic modeling.« less