Decision Tools to Evaluate Vulnerabilities and Adaptation Strategies to Climate Change Water Resources Sector Sebastián Vicuña University of California, Berkeley/SEI CGE Hands-on Training Workshop on V&A Assessments for the Latin America and the Caribbean Region Asunción, Paraguay, August 2006

Outline Vulnerability and adaptation with respect to water resources Hydrologic implications of climate change for water resources Tools/models WEAP model presentation Role for Multi-Criteria Analysis (MCA)

Effective V&A Assessments Defining V&A assessment Often V&A in the water sector focuses on analysis over assessment Why? Because the focus is on biophysical impacts, e.g., hydrologic response, crop yields, land use, etc. Assessment is an integrating process requiring the interface of physical and social science and public policy

Effective V&A Assessments (continued) General questions What is the assessment trying to influence? How can the science/policy interface be most effective? How can the participants be most effective in the process? General problems Participants bring differing objectives/ expertise These differences often lead to dissention/ differing opinions – this is where MCA can help in prioritization

Effective V&A Assessments (continued) To be valuable, the assessment process requires Relevancy Credibility Legitimacy Consistent participation An interdisciplinary process The assessment process often requires a tool The tool is usually a model or suite of models These models serve as the interface This interface is a bridge for dialogue between scientists and policy makers

The Water Resource Sector Water’s “Trade-Off” Landscape

Water Resources – A Critical V&A Sector Must consider both managed and natural systems Human activity influences both systems Natural Systems External Pressure State of System Little Control of processes Managed Systems External Pressure Product, good or service Process Control Example: Agriculture Example: Wetlands services

Outline Vulnerability and adaptation with respect to water resources Hydrologic implications of climate change for water resources Tools/models WEAP model presentation Role for Multi-Criteria Analysis (MCA)

Hydrologic ‘External Pressures’ related to Climate Change Precipitation amount Global average increase Marked regional differences Temperature increase Change in timing of streamflows Glacier retreat Precipitation frequency and intensity Less frequent, more intense (Trenberth et al., 2003) Evaporation and transpiration Increase total evaporation Regional complexities due to plant/atmosphere interactions

Specific Pressures: Annual Runoff Arnell., 2003 Change in annual runoff (A2 scenario)

Specific Pressures: Annual Runoff Arnell., 2003 Change in annual runoff (A2 scenario)

Specific Pressures: Annual Runoff

Specific Pressures: Runoff timing, analogy to North American West Stewart et al., 2004

Analogy with Western North America Temperature Topography Snow cover

Analogy with Western North America Temperature Topography Snow cover

Specific Pressures: Runoff timing, analogy to North American West Inflow spilled Refill lost

Specific Pressures: Retreating glaciers Comunicación Nacional del Perú a la UNFCCC Francou et al., 2000 Retroceso del glaciar Broggi Glaciar en 1979 y 1997 Fluctuación del frente de 4 glaciares en Perú Evolución del glaciar Chacaltaya (Bolivia)

Specific Pressures: Retreating glaciers Meltwaters are depended upon during dry season to sustain low flow periods Probable diminished volume and earlier timing of flows Has implications for hydropower production, agricultural demands, and river and riparian quality and ecosystem needs

Specific Pressures: Extreme weather Climate variability (El Nino/Nina Southern Oscillation) impact water availability and all economic sectors en several countries in the region (e.g. Peru, Ecuador, Central America) (IPCC 2001). Some climate models indicate more El Nino-like climate with increased greenhouse gases concentrations (Meehl and Washington 1996; Trenberth and Hoar, 1997)

Specific Pressures: Extreme weather Arnell., 2003 Change in extremes by the 2050s, under HadCM3

Specific Pressures: Extreme weather Arnell., 1999 Change in extremes by the 2050s, under HadCM3

Examples of Adaptation in Water Resources Construction/modification of physical infrastructure Canal linings Closed conduits instead of open channels Integrating separate reservoirs into a single system Reservoirs/hydro-plants/delivery systems Raising dam wall height Increasing canal size Removing sediment from reservoirs for more storage Inter-basin water transfers

Examples of Adaptation in Water Resources (continued) Adaptive management of existing water supply systems Change operating rules for reservoirs Use conjunctive surface/groundwater supply Physically integrate reservoir operation system Coordinate supply/demand Indigenous options

Examples of Adaptation in Water Resources (continued) Policy, conservation, efficiency, and technology Domestic Municipal and in-home re-use of water Leak repair Rainwater collection for non-potable uses Low-flow appliances Dual-supply systems (potable and nonpotable) Agriculture Irrigation timing and efficiency Drainage re-use, use of wastewater effluent High value/low water use crops Drip, micro-spray, low-energy, precision application irrigation systems Salt-tolerant crops that can use drain water

Examples of Adaptation – Water Supply (continued) Policy, conservation, efficiency, and technology (continued) Industry Water re-use and recycling Closed cycle and/or air cooling More efficient hydropower turbines Cooling ponds, wet towers and dry towers Energy (hydropower) Reservoir re-operation Cogeneration (beneficial use of waste heat) Additional reservoirs and hydropower stations Low head run of the river hydropower Market/price-driven transfers to other activities Using water price to shift water use between sectors

Outline Vulnerability and adaptation with respect to water resources Hydrologic implications of climate change for water resources Tools/models WEAP model presentation Role for Multi-Criteria Analysis (MCA)

Tools in Water Resource V&A Studies What tools are available to understand both water resource vulnerabilities and evaluate possible adaptation strategies? How can stakeholders be engaged in these processes?

Types of Water Resources Models Hydraulic: biophysical process models describing streamflow, flooding Hydrology: rainfall/runoff processes Planning: water resource systems models Which model?... What questions are you trying to answer?

Hydraulic Model Critical questions How fast, deep is river flowing (flooding effects) How do changes to flow and channel morphology impact sediment transport and services provided (fish habitats, recreation, etc).

Hydrology Model Critical questions How does rainfall on a catchment translate into flow in a river? What pathways does water follow as it moves through a catchment? How does movement along these pathways impact the magnitude, timing, duration, and frequency of river flows, as well as water quality?

Planning Model Critical questions How should water be allocated to various uses in time of shortage? How can these operations be constrained to protect the services provided by the river? How should infrastructure in the system (e.g., dams, diversion works) be operated to achieve maximum benefit (economic, social, ecological)? How will allocation, operations, and operating constraints change if new management strategies are introduced into the system?

Operational and hydraulic HEC HEC-HMS – event-based rainfall-runoff (provides input to HEC-RAS for doing 1-d flood inundation “mapping”) HEC-RAS – one-dimensional steady and unsteady flow HEC-ResSim – reservoir operation modeling WaterWare RiverWare MIKE11 Delft3d Tools to Use for the Assessment: Referenced Water Models

Hydraulic Water Management Model HEC-HMS watershed scale, event based hydrologic simulation, of rainfall-runoff processes Sub-daily rainfall- runoff processes of small catchments Free, download from web

Tools to Use for the Assessment: Referenced Water Models (continued) Planning/ hydrology WEAP21 Aquarius SWAT IRAS (Interactive River and Aquifer Simulation) RIBASIM MIKE 21 and BASIN

Current Focus – Planning and Hydrologic Implications of Climate Change Selected planning/hydrology models: can be deployed on PC, extensive documentation, ease of use, free (or free to developing nations)… Aquarius SWAT (Soil Water Assessment Tool) WEAP21 (Water Evaluation and Planning)

Physical Hydrology and Water Management Models AQUARIUS advantage: Has economic efficiency criterion requiring the reallocation of stream flows until the net marginal return in all water uses is equal Cannot be climatically driven – flows prescribed by user Economic focus

Physical Hydrology and Water Management Models (continued) SWAT advantage: Can predict effect of management decisions on water, sediment, nutrient and pesticide yields on ungauged river basins. Considers complex water quality constituents. Rainfall-runoff, river routing on a daily timestep Focuses on supply side of water balance

Physical Hydrology and Water Management Models (continued) WEAP21 advantage: Seamlessly integrates watershed hydrologic processes with water resources management Can be climatically driven Based on holistic approach of integrated water resources management (IWRM) – supply and demand

Outline Vulnerability and adaptation with respect to water resources Hydrologic implications of climate change for water resources Tools/models WEAP model presentation Role for Multi-Criteria Analysis (MCA)

Overview WEAP21 Hydrology and planning Planning (water distribution) examples and exercises Adding hydrology to the model User interface Scale Data requirements and resources Calibration and validation Results Scenarios Licensing and registration

WEAP and Planning Provides a common framework for transparently organizing water resource data at any scale desired – local watershed, regional or transboundary river basin Scenarios can be easily developed to explore possible water futures Implications of various policies can be evaluated

Uses of WEAP Policy Research Alternative Allocations Climate Change Land Use Change Infrastructure Planning Capacity Building Negotiation Stakeholder Engagement

WEAP Capabilities Can do High level planning at local and regional scales Demand management Water allocation Infrastructure evaluation Cannot do Sub-daily operations Optimization of supply and demand (e.g. cost minimizations or social welfare maximization)

A Simple System with WEAP

An Infrastructure Constraint Unmet

A Regulatory Constraint Unmet IFR Met

unmet Different Priorities For example, the demands of large farmers (70 units) might be Priority 1 in one scenario whereas the demands of smallholders (40 units) may be Priority 1 in another

Different Preferences For example, a center pivot operator may prefer to take water from a tributary because of lower pumping costs

WEAP is Scenario-driven The scenario editor readily accommodates analysis of: Climate change scenarios and assumptions Future demand assumptions Future watershed development assumptions

Futures and Scenarios: Why? Scenarios: a systematic way of thinking about the future To gain a better understanding of the possible implications of decisions (or non-decisions across scales and time To support decision-making

Driving Forces Demographic More people Urbanization Older Economic Growing integration of global economy Social Increasing inequality Persistent poverty Cultural Spread of values of consumerism and individualism Nationalist and religious reaction Technological Computer and information technology Biotechnology Miniaturization Environmental/Climatic Increasing global stress Local degradation Some remediation in richer countries Governance Global institutions Democratic government Role for civil society in decision-making

WEAP21 Program Structure

The WEAP21 Graphical User Interface Languages: Interface Only English French Chinese Spanish

Data Requirements WEAP allows the user to determine the level of complexity desired according to the questions that need to be addressed the availability of data

From the simple…

To the complex….

Data Requirements: Supply User-prescribed supply (riverflow given as fixed time series) Time series data of riverflows (headflows) cfs River network (connectivity) Alternative supply via physical hydrology (let the watershed generate riverflow) Watershed attributes Area, land cover... Climate Precipitation, temperature, windspeed, and relative humidity

User-defined Streamflows and Demands

Letting Climate Drive Hydrology

The WEAP 2-Bucket Hydrology Module Surface Runoff = f(P e,z 1,1/LAI) SwSw DwDw

One 2-Bucket Model per Land Class

Integrated Hydrology/Water Management Analytical Framework in WEAP21

Data Requirements: Demand Water demand data: multi-sectoral Municipal and industrial demand Aggregated by sector (manufacturing, tourism, etc.) Disaggregated by population (e.g., use/capita, use/socioeconomic group) Agricultural demands Aggregated by area (# hectares, annual water- use/hectare) Disaggregated by crop water requirements Ecosystem demands (in-stream flow requirements)

Data Requirements (continued) Agriculture Industry Municipal Cotton Rice Wheat... Electric Power Petroleum Paper... South City West City... Irrigation... Cooling Processing Others Single Family Multi-family... Furrow Sprinkler Drip Standard Efficient... Kitchen Bathing Washer Toilet... SECTOR SUBSECTOR END-USE DEVICE

Calibration and Validation Model evaluation criteria Flows along mainstem and tributaries Reservoir storage and release Water diversions from other basins Agricultural water demand and delivery Municipal and industrial water demands and deliveries Groundwater storage trends and levels

Modeling Streamflow

Looking at Results Select results to be viewed, including which scenario here. Change units and sub categories of results, and change the style of the graph here. Select values for the y here.

Outline Vulnerability and adaptation with respect to water resources Hydrologic implications of climate change for water resources Tools/models WEAP model presentation Role for Multi-Criteria Analysis (MCA)

What next? How can output from WEAP, or any water resource model for that matter, be organized and analyzed to prioritize and select appropriate adaptation strategies?... Stakeholder-driven multi-criteria analysis can help…

Multi-criteria Analysis (MCA) Any structured approach used to determine overall preferences among alternative options, where the alternatives can accomplish several objectives Is particularly useful to situations where a single criterion would fall short, and allows decision-makers to address a range of relevant factors

MCA: Scope All sectors, regions, livelihoods, ecosystems, etc. Has been used extensively in water resources planning, coastal zone management, agricultural development, and stakeholder processes

MCA: Key Outputs A single preferred option, or… A short list of preferred options, or… A characterization of acceptable and unacceptable possibilities

MCA: Key Inputs Evaluation criteria Relevant metrics for those criteria

MCA–WEAP: Motivation Develop an interactive computer tool to facilitate multi-criteria assessment of water resource options in a stakeholder context Designed specifically to be used in conjunction with outputs from the WEAP model and stakeholder processes to develop, weight and apply evaluation criteria to adaptation options

MCA–WEAP: History MCA-WEAP is a new Excel macros-based model, built off of NAPAssess, a tool developed by SEI for use by Sudan and Yemen in their NAPA processes Now reshaped to focus exclusively on adaptation options around water – used so far in Netherlands Climate Assistance Program (NCAP) studies ensure adequate stakeholder representation Identify CC adaptation strategies establish country-driven criteria to evaluate and prioritize Make consensus-based recommendations for adaptation initiatives Open source, and still a BETA version!

MCA–WEAP: Capabilities Streamlines the multi-criteria analysis process by: Housing all relevant project information on a single platform Supporting a transparent, user-friendly process for developing, weighting, and applying evaluation criteria Producing a ranked set of alternatives

MCA–WEAP: Steps Assess key vulnerability Identify key stakeholders Identify potential adaptation strategies Develop stakeholder-driven evaluation criteria to determine trade-offs Assign weights to criteria Prioritize adaptation options for best meeting the needs of those most vulnerable

Licensing WEAP Go to and register for a new license (free for government, university, and non-profit organizations in developing countries) Workshop assistants can have access to a temporary license with the following data: User Name: UNFCCC V&A Workshop Registration Code: License Expires : 10/31/2006