The potential value of flood emergency management decisions is limited to the quality of information available. For this reason, there has been increasing interest and realised need for decision support systems (DSS's) which can be developed to give predictions of real-time flood information. In this study, the relationships between flooding at gauged locations and ungauged, floodprone structures were investigated with the goal of developing algorithms to represent these relationships in real-time. A hydraulic model was developed for a portion of the Coomera River, Gold Coast, and an empirical function was used to represent the water level relationship between the John Muntz Causeway and a nearby stream gauge. This approach, of using water level input only, was found to be feasible for the real-time monitoring of the estimated water levels at the structure. It demonstrated that the processes of a one-dimensional hydrodynamic model can be substituted by an empirical relationship.