AGWA: Risk Management Framework for Water Resources Climate Adaptation Rolf Olsen,1 PhD Eugene Stakhiv,1,2 PhD 1Institute for Water Resources U.S. Army Corps of Engineers Alexandria, Virginia, USA 2Johns Hopkins University Baltimore , Maryland, USA Outline • Background on Alliance for Global Water Adaptation (AGWA) • Risk Management Framework – Breakout sessions – Next steps – stress tests • Examples – Flood risk – Reservoir regulation • Application of framework to United States-Canada Great Lakes Study – Example: ecosystems AGWA: A Brief Overview • The Alliance for Global Water Adaptation is a group of regional and global development banks, aid agencies and governments, a diverse set of non-governmental organizations (NGOs), and the private sector focused on how to manage water resources in way that is sustainable even as climate change alters the global hydrological cycle. • Focused on how to help practitioners, investors, and water planners and managers make systematic, consistent, and resilient decisions AGWA network • alliance4water.org Development banks and capacity-building groups. The World Bank, the Asian Development Bank, European Investment Bank, KfW, the Inter-American Development Bank, GiZ, the Cooperative Programme on Water and Climate. Non-governmental Organizations Conservation International, the Delta Alliance, International Water Association, the Swedish Environmental Institute (IVL), the Global Water Partnership, Deltares, Environmental Law Institute (ELI), Stockholm Environmental Institute (SEI), Organization for European Cooperation and Development (OECD), Stockholm International Water Institute, Wetlands International, IUCN, The Nature Conservancy, ICIMOD, WWF. Governmental US Army Corps of Engineers, US State Department, NOAA, UN Water, UN Habitat, UNECE, Water Utilities Climate Alliance, WMO, CONAGUA, Seattle Public Utilities, The Private Sector Ceres, UNEP FI, World Business Council for Sustainable Development Key partners Water & Climate Coalition, the Adaptation Partnership, the Global Environment Facility, Nairobi Work Programme Uncertainty Source: Wilby & Dessai, 2010, Weather Traditional approaches amplify or hide uncertainty • Models not developed for adaptation purposes but for testing hypotheses about greenhouse gas mitigation. • Low confidence, especially for quantitative purposes • Little agreement across models, scenarios • Often result in a series of “no regret” options • Stakeholders often feel disempowered by process, which is often experienced as deterministic Source: AGWA, “Caveat Adaptor,” 2013 UZH R. watershed [Dneister R. Basin] (Zhelezhniak, et al. 2013) Return Period, yrs 100 TOPKAPI (1961-1990) DHSVM (1961-1990) TOPKAPI (2011-2050) DHSVM (2011-2050) observed 80 60 40 20 0 0 200 400 600 Discharge, cms 800 Top-down vs. bottom-up approaches top-down approaches to risk assessment 1. Downscale climate model projections decision-scaling risk assessment 3. Assess plausibility and test vulnerability 2. Estimate shifts in water supply 3. Determine system responses to changes in these variables 2. Assemble multiple climate data sources and link to breaking points 1. Define your system’s breaking points Weaver et al., 2012, WIREs Climate Change Purpose • Purpose of these sessions: Develop a risk assessment of the performance of water resources management under the threat of future climate changes and variability using a ‘bottom-up’ approach. • A bottom-up approach is a stakeholder driven process to assess vulnerability rather than a reliance on predictive models of the future. Risk-Informed Decision Making Analyze Risks Evaluate Risks Monitor, Evaluate, Modify Identify Risks Risk Assessment Consult, Communicate and Collaborate Establish Decision Context Risk Mitigation Adapted from ISO 31000- Risk Management—Principles and Guidelines Background • Risk management has two basic parts: assessing risks and developing solutions. • Risks can be assessed either qualitatively or quantitatively • Vulnerabilities such as flood inundation and flood damages can be quantified. • Other vulnerabilities (ecosystems) can be categorized qualitatively by stakeholders in terms of ‘coping zones’ and relative degrees of ‘risk tolerance.’ • Risk management options (solutions) need to take into account both types of information. Defining System Objectives • For each sector (flood risk, ecosystems, and agriculture), what specific objectives are you trying to achieve? – Flood risk examples: reduce long-term flood damages; reduce vulnerability of infrastructure to disruption; reduce human fatalities from flooding – Ecosystem examples: improve biodiversity; preserve wetlands; increase fish stocks – Agriculture examples: increase agricultural production; increase farm income Measuring System Performance • What metrics would you use to define success or failure? – Flood risk examples: reduction in flood damages – Ecosystem examples: biodiversity indicators; fish biodiversity and catch amounts; health of indicator species – Agriculture examples: area of land irrigated; crop yields • A metric is a measurable quantity that can be used to measure the performance of a system. Identify Problems • Identify climate concerns, hazards and thresholds. What river flow and climate conditions are associated with these hazards? – Flood risk: What are the current flooding problems in the Dniester river basin? At what flood water levels and flood flow values are populations affected? At what flood water levels and flood flow values does major infrastructure become unusable? – Ecosystems: What are the current major ecosystem problems? What is the major source/cause of ecosystem disruption (infrastructure, floods, droughts, or pollution)? What river flow values support these ecosystems? How has drought affected ecosystems? Have changes in flow patterns caused by reservoir regulation altered ecosystems? – Agriculture: What are the current problems for irrigated agriculture? Discuss problems during past droughts. Non-climate Causes of System Stress • Identify key drivers and stressors. – Drivers are forces that can have major influences on the system of interest. Potential drivers could be of physical, biological or economic origin (i.e., climate, invasive species, population growth, etc.). – Stressors are changes that occur that are brought about by the drivers. – Examples: • Flood: population living in floodplain; important infrastructure in flood plain • Ecosystems: water quality (toxic chemicals, dissolved oxygen, water temperature); overfishing; invasive species • Agriculture: irrigation infrastructure not performing as designed; soil fertility Risk Tolerance • Risk tolerance is the willingness to bear a known risk based on its severity and likelihood • What range of conditions would have unfavorable though not irreversible agricultural impacts? How often can you tolerate such conditions? – Flood examples: disruption of transportation; damaged homes; reduced economic output – Ecosystem examples: loss of wetlands; diminished fish stocks – Agricultural examples: reduced farm income; lower agricultural productivity • What range of conditions would have severe, long-lasting or permanent adverse impacts? – Flood example: population does not return and rebuild after a flood – Ecosystem example: extinct species – Agricultural examples: farmland is abandoned Coping Range: Coping range represents the magnitude or rate of disturbance various systems like communities, enterprises, or ecosystems can tolerate without significant adverse impacts or the crossing of critical thresholds. Resilience Range: Resilience range is the magnitude of damage a system can tolerate, and still autonomously return to its original state. Failure Range: Failure range starts from the point where magnitude of damage is such that a system can no longer tolerate it without significant adverse impacts. Risk Matrix Likelihood • Likelihood is the chance of something happening, whether defined, measured or determined objectively or subjectively, qualitatively or quantitatively. • Statistical models are generally based on assumption of stationarity, that is the past is representative of future. • Estimating probabilities for Global Climate Models is problematic; uncertainty is not quantifiable. Confidence • Confidence is the validity of a finding based on the type, amount, quality, and consistency of evidence (e.g., mechanistic understanding, theory, data, models, expert judgment) and on the degree of agreement (Intergovernmental Panel on climate Change Fifth Assessment Report, 2013). • Our confidence in the likelihood and potential consequences will influence our decision. Robustness Tests • How well does the system remain functioning under a range of circumstances? • System is tested with an array of approaches – – – – Observed hydrology Stochastic hydrologic sequences Global climate model projections ‘Weather generator’ if available • Test risk management solutions across a range of possible conditions. Stress test: drought characteristics Duration, Severity and Intensity Severity = Volume/Duration Stress test: climate events 4000 640 Historical Climate 1 Historical - lake level Climate 1 - lake level 3500 635 630 2500 2000 625 1500 620 1000 615 500 0 610 1 13 25 37 Month # 49 Lake level (ft.) Monthly average inflow (cfs) 3000 Dniester Basin Flooding LEB - Lower Error Bound Q S Frequency Flood Discharge (Q) P Q Flood Stage (S) UEB - Upper Error Bound Frequency Flood Stage (S) Uncertainty and Flood Damage Calculation UEB LEB S D Flood Damage (D) P D Flood Discharge (Q) Flood Damage (D) U.S. Army Corps of Engineers Procedures - HEC-FDA;1992 Quantifying Frequency Description Flood Zone Coping Range Remote Mid-point estimated frequency Approximate Rank numerical value events/ year 1 in 500 yr 0.002 1 1 in 100 yr 0.01 2 1 in 20 yr 0.05 3 Occasional Flood Zone 1 <1 : 200 years 1:50 yrs - 1: 200 Flood Zone 2 years 1:10 years to 1: 50 Flood Zone 3 years Flood Zone 4 1:5 yrs to 1:10 yrs 1 in 7 yr 0.15 4 Frequent Flood Zone 5 1:2 yrs to 1:5 yrs 1 in 4 yr 0.25 5 Regular Flood Zone 6 1:1 yr to 1:2 yrs 1 in 1.5 yr 0.50 6 Common Flood Zone 7 0.2 yr to 1:1 yr 1 in 0.3 yr 0.70 7 Rare Infrequent Frequency Range Quantifying Severity/Consequences Economic/Safety/Health Approximate Numerical value Description Ranking Equivalent fatalities per event Minor Damages < $ 103/ 0.005 More serious damages e.g. multiple minor injuries Major injuries/property damage 2 (significant) 3 (moderate) Multiple Major / single fatality 4 (Major) Multiple fatalities (1-10) Severe economic damages Multiple fatalities (10 to 100) Catastrophic damages Multiple fatalities (>100) 1 (minor) 5 6 (Severe) > $109/1000 fatalities 7 (catastrophic) Choosing Management Alternatives Dniester Dams and Reservoirs Reservoir Regulation • Potential adaptation measures – Provide more naturalized flow patterns for ecosystems while maintaining economic benefits – Change allocation of storage space to different uses – “Dynamic rule curves”: Shift reservoir storage allocation based on current hydrological conditions in basin. – More use of forecasts in reservoir operations Reservoir Rule Curves and Storage Allocation Allocation of Reservoir Storage Space New Bullards Bar Reservoir, California, USA Less Precipitation Shasta Reservoir, California, USA More Precipitation