There is growing evidence that hydro-meteorological events, and particularly floods, are the most frequent cause of disasters for many places around the world. Nature-Based Solutions (NBS) have been introduced to address these growing risks and they have a potential to be more effective than traditional grey infrastructure. NBS offer a way forward, enabling us to adapt to anticipated changes in climate and society while achieving multiple benefits for ecosystem services and functions. However, scientists and decision-makers require holistic perspectives and frameworks to help understand, evaluate and design NBS in such a way that can reduce social, economic and environmental impacts, increase resilience to hydro-meteorological events and enhance the co-benefits. This book presents a methodological framework for the evaluation of Nature-Based Solutions for hydro-meteorological risk reduction and co-benefits enhancement. The evaluation framework consists of two main evaluation processes, which are ex-ante evaluation and ex-post evaluation. The ex-ante evaluation was applied to the Tamnava river basin, Serbia, while the ex-post evaluation was conducted in the Rangsit area, Thailand. The results of this research contribute to the improvement of decision-making and NBS evaluation processes, both before and after NBS implementation. They offer valuable insights for practitioners and researchers to enhance the effectiveness and credibility of NBS, considering their risk reduction benefits and co-benefits. @en

Nowadays, economic development, urbanisation and heavy rainfall events are present in urban areas. A major change in approaches to the management of flooding is also ongoing in many countries worldwide. There are some decision support system tools available to evaluate green and grey infrastructures across a wide range of conditions as well as to compare alternative options. However, the performance of urban drainage systems that combines different green-grey solutions is still unclear. The present book introduces a framework for evaluation of the performance of green and grey infrastructures for runoff and pollutant reduction. To this end, it presents an evaluation of how different combinations of green infrastructure (GI) measures perform within a drainage system to reduce runoff and pollution and how the interactions between different grey infrastructures can influence the drainage system capacity. The modelling approach introduced here also combines the infiltration process, overland flow and sewer system interactions to assess the optimal combination of green-grey infrastructures for urban flood reduction. The results of this research demonstrate that including rainfall-runoff and infiltration processes, along with the representation of GI within a 2D model domain, enhances the analysis of the optimal combination of infrastructures, which in turn allows the drainage system to be assessed holistically. @en

The negative impacts of floods are attributed to the extent and magnitude of a flood hazard, and the vulnerability and exposure of natural and human elements. In flood risk management (FRM) studies, it is crucial to model the interaction between human and flood subsystems across multiple spatial, temporal and organizational scales. Models should address the heterogeneity that exists within the human subsystem, and incorporate institutions that shape the behaviour of individuals. Hence, the main objectives of the dissertation are to develop a modelling framework and a methodology to build holistic models for FRM, and to assess how coupled human-flood interaction models support FRM policy analysis and decision-making. To achieve the objectives, the study introduces the Coupled fLood-Agent-Institution Modelling framework (CLAIM). CLAIM integrates actors, institutions, the urban environment, hydrologic and hydrodynamic processes and external factors, which affect FRM activities. The framework draws on the complex system perspective and conceptualizes the interaction of floods, humans and their environment as drivers of flood hazard, vulnerability and exposure. The human and flood subsystems are modelled using agent-based models and hydrodynamic models, respectively. The two models are dynamically coupled to understand human-flood interactions and to investigate the effect of institutions on FRM policy analysis.@en