Optimization of preventive drought management measures to alleviate the severity of agricultural and hydrological droughts

Preventive Drought Management Measures (PDMM) aim to reduce the chance of droughts and minimise their negative consequences in the short and long term. A wide range of interventions can be considered PDMM, including Nature-Based Solutions, grey infrastructure, land use management, and soil conservation practices, among others. This study intends to apply an optimisation procedure to find optimal combinations and allocations of PDMM that contribute to minimising the agricultural and hydrological drought's severity at a basin scale. To achieve this goal, we coupled the multi-objective genetic algorithm (NSGA-II) with the semi-distributed hydrologic model, Soil and Water Assessment Tool (SWAT). The PDMM evaluated in this study are rainwater harvesting ponds, parallel terraces, forest conservation, grade stabilisation structures and floodplains restoration. Preliminary results indicate that optimal combinations and allocations of PDMM reduce the drought's severity in downstream subbasins. The analysis was developed in the La Vieja basin (West-central Colombia).