Effects of Uncertain Control in Transport of Water in a River-Wetland System of the Low Magdalena River, Colombia

During the 2010 and 2011, extreme flooding events affected the low Magdalena River catchment, Colombia, with devastating consequences. This triggered the urgency of adjusting the new river basing planning framework for the country, in which the generation and use of flood risk maps, was lacking. Recent efforts include the generation of probabilistic flood maps, based on the generation of a hydraulic model and an uncertainty analysis related to the wetland-river connections. Although this effort is a step forward to the definition of design criteria for flood risk prevention measures and for the land-use planning process in general, an integrated vision is still missing. In particular, depending on the hydraulic and hydrological condition of the river-wetland system, the operation of the existing hydraulic structures is sometimes decided illegally by the water users with the strongest economical power and not by the local authority, with the consequent biased water use. The research objective of this study is to analyze the control strategy for the operation of hydraulic structures in the region of the Low Magdalena River, considering uncertain control due to self-operation of the structures by non-official actors. The study includes a literature review on existing methodologies and cases where control structures are significant and where conflicting interests are present. A number of different scenarios are analyzed different control scenarios are tested. The study uses the recently developed 1D–2D model of the region that simulates the Magdalena River Channel with side structures that replicate the river-wetland connections. Conclusions and recommendations of the study are drawn, as well as indications of activities for future research.