Multi-criteria decision-making (MCDM) methods have been used to prioritise structural flood control options for the effective management of flood risks. A recent study carried out by researchers from Iran and Poland has provided valuable insights to help assist policymakers and stakeholders in effectively allocating resources and implementing appropriate structural flood control measures.
Multi-criteria decision-making approaches are described as offering “a systematic framework for evaluating and ranking various flood control measures based on multiple criteria”. This approach considers the complex and multidimensional nature of flood management, including both technical and non-technical aspects, such as cost-effectiveness, environmental impacts, social acceptability, and resilience.
According to the authors Hamidifar et al in their work published in The Journal of Flood Risk Management, the increasing complexity and uncertainty associated with decision-making in the field of hydrology has given the application of MCDM methods more prominence.
The main aim of their study was to offer decision-makers, flood control engineers, and researchers a thorough understanding of the strengths, limitations, and practical implications related to prioritising different structural flood control solutions. This was achieved by utilising a range of predefined criteria and employing four MCDM techniques.
Study area
The study area encompassed approximately 15,563km2 of the Kohgiluyeh and Boyer-Ahmad Province in southwestern Iran. With an average annual rainfall of 550mm and a moderate temperature range of 15 to 26oC, the province is known for its diverse topography. The main rivers of Maroun, Khersan, Zohre, Beshar, Nazmakan, and Marbor, also pose significant flood risks during heavy rainfall and snowmelt events. In the past, decision makers have put forth various development proposals for flood control, and several small and large dams have been built on the rivers in the province – the most notable being the Kowsar, ShahQasem, and Chamshir dams.
According to the authors, analysis undertaken during the study highlights the varying importance of criteria for different options, emphasising the need to consider multiple criteria in decision-making. The study found that the analytic hierarchy process (AHP) and technique for order of preference by similarity to ideal solution (TOPSIS) methods, confirmed the prominence of reservoir dams. However, according to both the multicriteria optimisation and compromise solution (VIKOR) and Fuzzy-VIKOR (FVIKOR) models, the retention basin is ranked as the top priority for flood control. Levees also emerge as an important option and were higher up in the rankings. Conversely, flood control gates and the no-project conditions received the lowest ranks, suggesting their limited effectiveness in addressing flood hazards. Overall, the authors explain that the various multi-criteria decision-making methods provide diverse rankings due to differences in methodologies, criteria weighting, treatment of uncertainty, aggregation techniques, sensitivity to input data, and assumptions.
Hamidifar et al collude that the results “emphasise the importance of considering multiple methods and their underlying factors when evaluating and prioritising flood control options”. This study offers practical applications for enhanced flood risk management and decision-making so that “policymakers can utilise the prioritised flood control solutions, focusing on dams, retention basins, and levees, to make informed policy decisions”.
Furthermore, the authors add that local authorities can communicate the significance of these measures, leveraging insights on lower priorities for flood control gates and no-project options to educate communities and foster cooperation. Emergency management agencies can also integrate these prioritised solutions into their plans.
Additionally, the authors conclude that the prioritisation of flood control options can act as a benchmark for comparative studies in different regions, aiding researchers and decision-makers in adapting successful strategies to diverse conditions.
Ethiopian plans
The study titled “Utilizing multi-criteria decision-making analysis and 3D visualization techniques for dam site selection and irrigation area identification in Gedeb River, Ethiopia” explores an integrated approach to identifying an optimal dam site and suitable irrigation areas in the Gedeb River basin. Water resource management is crucial for sustainable agricultural development, particularly in regions prone to drought and seasonal water scarcity. The research combines remote sensing, GIS-based multi-criteria decision-making (MCDM) methods, and expert judgment to assess potential locations for water storage and irrigation expansion.
To achieve its objectives, the study incorporates a diverse range of environmental, geological, and hydrological factors. These include precipitation levels, river discharge rates, geological structures, soil characteristics, topographical features such as elevation and slope, and land use patterns. Additionally, the researchers consider proximity to fault lines and landslide-prone areas to ensure the long-term stability and feasibility of dam construction. The integration of these factors allows for a comprehensive analysis that balances environmental sustainability, technical feasibility, and economic viability.
The study’s findings indicate that a 1,886-hectare area is optimal for an irrigation water storage dam, with a total storage capacity of approximately 2.96 billion cubic meters. In terms of irrigation suitability, the analysis categorises the land into highly suitable (18,362.05 hectares), moderately suitable (19,204.05 hectares), marginally suitable (2,095.25 hectares), and unsuitable (2.89 hectares). These classifications are based on factors such as soil fertility, water availability, and terrain conditions. The identification of these irrigation zones is essential for policymakers and agricultural planners, as it provides a scientific basis for expanding irrigation infrastructure while minimising environmental risks.
A key strength of the study is its use of 3D visualisation techniques, which offer a more intuitive and detailed representation of the terrain and hydrological features. These visual models enhance the decision-making process by allowing stakeholders to better understand the spatial distribution of water resources and potential irrigation zones. This approach is particularly valuable for government agencies, non-governmental organisations, and investors looking to support sustainable agricultural development in Ethiopia.
Beyond its technical contributions, the research also highlights the socio-economic implications of water resource management. Improved irrigation infrastructure has the potential to increase agricultural productivity, enhance food security, and provide economic benefits to local communities. However, the study emphasises that successful implementation requires collaboration among government authorities, local farmers, environmental experts, and engineers. Engaging stakeholders in the planning process ensures that the selected dam site aligns with community needs and minimises potential conflicts over land and water use.
The authors stress the need for further research to refine their findings. Future studies could incorporate climate change projections to assess how shifting rainfall patterns and temperature variations might impact water availability in the region. Additionally, socio-economic factors such as land tenure systems, farmer preferences, and local governance structures should be considered to create a more holistic approach to water management. A detailed cost-benefit analysis of the proposed dam project would also be essential to determine its financial feasibility and long-term sustainability.
In conclusion, this study provides a comprehensive and scientifically rigorous framework for dam site selection and irrigation planning in the Gedeb River basin. By integrating MCDM methods, GIS technology, and 3D visualisation tools, the research offers valuable insights for optimising water resource management in Ethiopia. Its findings have significant implications for policymakers, development agencies, and agricultural planners seeking to enhance irrigation infrastructure, improve food security, and promote sustainable land use in the region. The study ultimately underscores the importance of a multidisciplinary approach in addressing complex environmental and socio-economic challenges associated with water resource management.
