A pseudo-reservoir concept in SWAT model for the simulation of an alluvial floodplain in a complex tropical river system

Abstract Study region The new formulation was applied in a complex tropical river system of Luanginga sub-basin, western Zambia. Study focus We propose a novel pseudo-reservoir concept (hereinafter PSRC) in the framework of the Soil and Water Assessment Tool (SWAT), to mimick and model the behavior of an alluvial floodplain. Outflows from PSRC are predicated on a conceptual storage-outflow-stage relationship, and decomposed into overflow and baseflow by considering floodplain hydrogeomorphic attributes and their dynamics in relation to critical bankful height. The model was tested for its skill to improve simulation of discharge. It`s performance was evaluated against SWAT targeted release reservoir and a configuration without a reservoir. New hydrological insights We demonstrated that PSRC via its parameters was dynamically and significantly (p-value