Hydro-economic models can serve as valuable tools to improve the understanding of system details, as well as to support decision-making and water resources management. However, hydro-economic models are not practically implemented as intended and are mainly used in academic settings due to their complexity and data requirements. This study presents a holistic hydro-economic framework for sustainable water resources management, in a simple and understandable way for policy-makers. It is examined under various management, climate and pricing scenarios. The proposed framework is based on: (a) the modeling of water balance and (b) the use of various hydro-economic outputs (e.g., irrigation water value, farmers' utility, efficiency indexes, direct costs, etc.). The proposed methodology can be applied to data-scarce areas, such as the Lake Karla watershed, Greece. Lake Karla watershed is a typical rural Mediterranean area. The results are encouraging on hydro-economic modeling with limited data, indicating that the establishment of a new management approach could be very beneficial in terms of water use efficiency. Hence, this research can provide an appropriate and suitable approach for facilitating water management in agricultural areas and for implementing the European Framework Directive 2000/60/EC.

Water is involved, directly or indirectly, with many activities and needs that have to be met. The large scale and importance of water projects, the investments needed, the difficulty in predicting the results, and the irreversible character of the decisions have made decision making a complex scientific process. This paper presents a multicriteria analysis (MCA) tool for evaluating water resource management (WRM) strategies and selecting the most appropriate among them, using as an example a Greek area based on agricultural economy, which faces water scarcity problems. Seven alternative strategies were evaluated under hydrological and economic criteria. Four techniques were used—multi attribute utility theory (MAUT), analytic hierarchy process (AHP), elimination and choice expressing reality (ELECTRE), and technique for order of preference by similarity to ideal solution (TOPSIS)—based on the main MCA techniques (utility theory, analytical hierarchy, outranking theory, and classification theory, respectively), to compare their performance, and to reach the most appropriate and ‘fitting’ method for the examined problem. The weightings extracted from two samples, (i) a sample of decision makers/stakeholders and (ii) a group of WRM experts, were used to compare the results. The process was carried out for each questionnaire, and thus the model shows the uncertainty of each sample group and of each method, as well as the overall uncertainty. The results illustrate the reality of the WRM problems of the watershed, enlighten their roots, and have further strengthened our conviction that the cooperation between the scientific community and the authorities is vital for more sustainable and efficient WRM.

The requirements of the Water Framework Directive (WFD) 2000/60 for the full water cost recovery have brought reactions and difficulties to their implementation, especially for irrigation water. We propose a systematic and objective methodology for the estimation of the cost of irrigation water. The application is made in a degraded Greek watershed, considering surface and groundwater resources. The main novelties of this study are: (i) the attempt to combine different approaches for the estimation of the 'resource cost' of irrigation water, and (ii) the investigation of the potential interaction between resource and environmental cost in order to avoid the overestimation of the full cost of water. The analysis shows that both resource and environmental costs can be high in degraded areas, and water policy is likely to affect these costs. Therefore, further analysis is needed on possible water pricing policies for recovering the full cost of irrigation water.

Undertaking integrated and sustainable water resources management (ISWRM) and providing socially acceptable solutions with scientifically solid bases is a dynamic and challenging process. Two basic pillars–umbrellas can be identified in the literature: stakeholder engagement and analysis; and integrated monitoring–modelling in the form of a decision support system (DSS) that can assess, evaluate and rank the management options. This study presents a framework that can be used as a good-practice example of successful stakeholder engagement (public engagement and collaboration with local communities towards shared visions) and an integrated DSS for ISWRM (including characterisation at catchment and local scales, programmes of measures and their evaluation): the Framework for Integrated Land and Landscape Management (FILLM), developed by an Irish multi-disciplinary and multi-stakeholder platform, the Water Forum. The fundamental theoretical principles and practical aspects of the FILLM are analysed. A step-by-step guide is proposed for its application, bridging the above pillars, using examples, reviewing methods and software, and analysing challenges and trends. It can help both socio-economic and environmental scientists (modellers) understand each other’s roles and find reviews of useful tools and methods for their work. This work can be a reference point for future ISWRM and environment management and can contribute to holistic education on such topics.

Fluvial floods are one of the primary natural hazards to our society, and the associated flood risk should always be evaluated for present and future conditions. The European Union’s (EU) Floods Directive highlights the importance of flood mapping as a key stage for detecting vulnerable areas, assessing floods’ impacts, and identifying damages and compensation plans. The implementation of the EU Flood Directive in Greece is challenging because of its geophysical and climatic variability and diverse hydrologic and hydraulic conditions. This study addressed this challenge by modeling of design rainfall at the sub-watershed level and subsequent estimation of flood design hydrographs using the Natural Resources Conservation Service (NRCS) Unit Hydrograph Procedure. The HEC-RAS 2D model was used for flood routing, estimation of flood attributes (i.e., water depths and flow velocities), and mapping of inundated areas. The modeling approach was applied at two complex and ungauged representative basins: The Lake Pamvotida basin located in the Epirus Region of the wet Western Greece, and the Pinios River basin located in the Thessaly Region of the drier Central Greece, a basin with a complex dendritic hydrographic system, expanding to more than 1188 river-km. The proposed modeling approach aimed at better estimation and mapping of flood inundation areas including relative uncertainties and providing guidance to professionals and academics.