Pontificia Universidad Catolica de Chile/Centro de Cambio Global1, Pontificia Universidad Catolica de Chile/Departamento de Ingenieria Hidraulica y Ambiental2
Observed climate change effects are challenging government and societies to start thinking how to adapt to the even more extreme range of potential future changes that will impact every aspect of our lives. As this need for adaptation arises so does the practical details about how to successfully implement this adaptation process given the socio-ecological complexity of systems that need to adapt. The Maipo river basin in the semi-arid Central Chile is an example of such complex socio-ecological systems that probably will need to adapt in the future due to climate change. This river provides water for over six million people and to more than 200.000 hectares of agricultural land and many other productive (e.g. mining, hydropower) and not productive activities in the Santiago Metropolitan Region (SMR). Previous studies have shown that future temperature and precipitation changes will result in more stress to the already water scarce basin but also could result in extreme flood events due to rising cero degree isotherm. If the populated and increasingly growing city of Santiago de Chile, wants to respond to the food, development and energy demands in an uncertain future with climate change, the public, private sector and civil society will require information and tools to make better decisions about water and land management. To respond to this need, a three-year project (2012-2015) entitled MAPA (Maipo Adaptation Plan for its initials in Spanish) is being implemented in collaboration with a multi-stakeholder platform of around 30 public, private and civil society organizations, both at the local and regional level. The objective of the project is to both identify vulnerabilities and adaptation options to potential future scenarios in the basin. This project builds-up from the experience of the Robust Decision Making framework that incorporates both stakeholders expertise and computational capabilities in a mutual feedback process to identify future scenarios, appropriate tools and models, adaptation measures and very importantly Performance Indicators. The latter allows both the identification of base line vulnerability levels but also understanding the benefits of implementing adaptation measures given uncertain scenarios. In a basin scale project such as MAPA, considering water as the common link between the diversity of threats and demands at different scales, it makes sense to use factors related to this resource as components of these Performance Indicators. Water Security is a commonly used but still contested concept with varied definitions and operationalization approaches. The Water Security definition by the U.N. Water Agenda was used in this project as a novel approach to frame a participatory process to identify Performance Indicators that are local-based, multi-scale and measure climate change impacts in a way that could trigger the implementation of adaptation measures. In order to operationalize the concept into the adaptation process we have disaggregated the water security into five sub-components that range from the different potential considerations of water as a resource to the considerations of it as threat also. Form this sub-components we have obtained a potential list of suggested indicators denoting water security for those sub-components and three sub-sectors under study: mountain, rural and urban sub-sectors. This guided but still highly participatory process based on continuous stakeholder feedback identifies causal links and scales of these indicators until finally define metrics and optimum levels to use as early signs in an adaptation plan. In defining these causal links, it is not our objective then only to measure water security, but to see beyond water physical manifestation into the potential uses or crucial objectives that are satisfied by access or avoidance of water and that could be finally impacted by climate change. This approach to identify Performance Indicators has the potential to capture the general aspirations of the different users in a basin related with economic development, ecosystem conservation, basic human needs, pollution and hazard allowing in this way not only the design of adaptation measures that have a physical water representation but also measures that are closely related to the final objectives that water security tries to achieve.