Bottom-Up Performance Based Approaches and Tools to Enhance Water Security from the Deep Uncertainties of Climate Change


There is a new community of practice that is moving away from top-down vulnerability assessments that begin by identifying and selecting futures that are used to examine system vulnerability and, if vulnerable, plan for, and focus on planning to avoid chronic failure of a system. In bottom-up vulnerability procedures, the use of projections about the future are used to examine the plausibility and analytical uncertainty of chronic failure. Bottom-up approaches are a performance driven process, while top-down approaches are a future projection driven process. In other words, in bottom-up approaches, climate science is used to evaluate the plausibility of failure, and help drive a decision scaling process. This session will seek to share experiences using this paradigm shift that originated with the publication of the Decision Tree Framework by the World Bank (, and later complemented by CRIDA published by UNESCO (
 The session will begin describing general principles and experiences . Then it will focus on presenting and discussing case studies that start the planning problem formulation from understanding of what external stressors causes a system to chronically fail, which could be combinations of external stressors are usually combinations of O&M, demographics, demand, urbanization, markets, societal preferences, and of course, Climate Change. The presentation of tools and data necessary to accomplish this approach are also welcome. The process is essentially geared to risk informed decision making, which could include, risk management, risk assessment and risk communication. The session will end with a plenary discussion with the goal is to narrow the gap between scientists and planners that need to develop plans that ensure water security into the unknown future.

Hosted by

Ad Jeuken

Expert advisor Climate Change Adaptation and Water

Guillermo F. Mendoza

IWR International Program Manager
U.S. Army Corps of Engineers Institute for Water Resources