Abstract This paper introduces EcoFlex, a novel modelling script for assessing ecological flow time series in rivers through an integrated simulation–optimization framework. Designed to support sustainable water management at both individual hydrometric stations and the catchment scale, EcoFlex employs advanced fuzzy logic systems—ranging from fully manual rule-based models to data-driven systems optimized using particle swarm optimization—to simulate aquatic habitat suitability based on physical parameters. The model is applicable in contexts with abundant data, limited data, or even no quantified physical habitat data. An evolutionary optimization algorithm is then used to assess ecological flow regimes, balancing the needs of ecosystem preservation with water withdrawal demands. EcoFlex supports both observed flows data and simulated flows, providing flexibility across different hydrological contexts. The model allows users to define a minimum flow threshold as well as minimum acceptable physical habitat suitability, ensuring reliable ecological flow delivery across all time steps while accounting for both habitat suitability and additional ecological considerations. In a real-world case study, the model successfully identified ecological flow regimes allowing for an average 30% withdrawal while preserving 70% for ecological needs. The resulting reduction in habitat suitability was minimal, with the habitat suitability index declining only slightly from 0. 70 to 0. 66—demonstrating EcoFlex’s effectiveness in sustaining riverine ecosystems under optimized ecological flow regimes. This outcome highlights the tool’s practicality, reliability, and cost-effectiveness for ecological flow assessments. The architecture of EcoFlex is designed for scalability, with future enhancements planned to incorporate a broader range of optimization algorithms and additional environmental factors, advancing it toward a hybrid ecological flow framework. The first version, EcoFlex M2025a, developed in MATLAB, is publicly available and ready for application in watershed management projects at: https: //github. com/msedighkia/SEMFAP/blob/main/EcoFlexM2025aFreeMode. zip
Sedighkia et al. (Sun,) studied this question.