Deltas are dynamic landforms at the boundary of land and sea, involving intricate mazes of rivers and small waterways, wetlands, estuaries and coastal barrier islands. They are home to over half a billion people. Deltas are also home to rich ecosystems, such as mangroves and marshes. They are economic hotspots, supporting much of the world’s fisheries, forest products, and extensive agriculture. Yet, delta systems are under threat from sea-level rise, cyclones, river flooding, storm surges, rapid urbanization, agricultural over-use and pollution, salinization, sediment starvation, coastal erosion, and natural and man-made subsidence. One of the missions of the Delta Alliance is to support the development and proliferation of new approaches in delta management through research, exchange of best practices and outreach of concepts and ideas. This report provides an overview of new approaches emerging in several deltas that can be labelled under the heading of Adaptive Delta Management. Adaptive management can be defined as a structured, iterative process of robust decision making in the face of uncertainty, with an aim to reduce uncertainty over time via system monitoring. Applying adaptive management to deltas is relatively new and one of the first explicit uses is by the Dutch Delta Program. The Dutch Delta Program formulates Adaptive Delta Management (ADM) as phased decision-making that takes uncertain long-term developments into account explicitly and in with transparency towards society. Adaptive delta management encourages an integrated and flexible approach to land and water management with to aim to reduce vulnerability limit the risk of over- or underinvestment in future challenges such as flood risk management and freshwater supplies. This report shows that ADM is developing rapidly into a fascinating new type of decision making under an uncertain future. The reasons for using the new approach are convincing, the theoretical foundation is growing and the results on the ground are promising. Adaptive Delta Management can be captured as a cyclic process of which the overall design does not differ much from traditional planning steps. However, the approach and methods within each step contain new elements, such as long term scenario building, adaptation pathway developments, signposts and triggers. In this report we distinguish the following building blocks for ADM: Connecting short term investments with long term challenges As part of ADM a planner should create a strategic vision of the future, commit to short-term actions and establish a framework to guide future actions. Typical in ADM is that such a vision has a longer time horizon than usual in planning activities (e.g. a century), in order to capture the long term processes of climate change. So instead of focusing on short-term ‘trial and error’ actions and projects, the idea is to keep the long term vision in mind while prioritizing short-term ‘no regret’ actions. Scenario development is an important tool in this process, against which strategies can be tested to see how robust these strategies are. Path dependency and adaptation pathways The history of deltas shows developments which, once started, cannot easily be changed or adapted to new conditions. This is what we call path dependency: the extent to which a policy action is limited by actions implemented in the past or by actions planned anterior in the pathway. Learning from the past and knowing that we cannot predict the future this leads us to the ambition to avoid Towards a comprehensive framework for adaptive delta management June 2014 Delta Alliance 3 such lock-ins. One way to do this is to use adaptation pathways: i.e. a sequence of policy actions over time that is able to achieve a set of objectives. Avoidance of over- and under investments Insight in the adaptation pathways is not only relevant for the required flexibility of measures, but also in view of the risks of over- or under-investments. Underinvestment occurs if it turns out that the solutions are not adequate. Overinvestment on the other hand happens when measures are over dimensioned, which proved unnecessary and therefore too expensive. Connecting public and private (investment) agendas Another building block for ADM is to actively search for windows of opportunity to combine different investment agendas, either within the public domain or between public and private investments. This way measures may be easier (and cheaper) to implement and yield more added (societal) value. The way forward Three phases can be defined in applying ADM. The first phase focuses on identification of current and future problems and challenges based on relevant future scenarios. In the second phase options are explored which might enhance the sustainability and/or reduce the vulnerability for both current threats and longer term uncertain futures. The last phase focuses on integrating the adaptation options into viable management strategies and ensuring their proper implementation. Until now the first two steps are gaining momentum, although more knowledge is needed on how deltas as complex dynamic systems work. How to link the second and the third step, where financing arrangements, public (infrastructure) procurement strategies, implementation constraints and opportunities as well as durable maintenance arrangements play a decisive role, is yet to be explored. We can potentially learn much by analyses of best practices which take into account the diversity in social and cultural dimensions. These practical experiences can thus generate a larger body of knowledge on delta planning and management.