This study proposes an inexact sequential response planning (ISRP) approach for floodplain management on the basis of two-stage stochastic programming techniques. It can facilitate rapid response decision making for upcoming severe flood disasters by efficiently operating available multiple control measures in a quantified manner. The case study considers a floodplain management problem where decision makers want to obtain a cost-effective combination of multiple floodplain management policies (i.e. constructing hydraulic engineering, flood diversion) for coping with the upcoming flooding disasters with various severity levels. Optimal management strategies obtained from ISRP are analyzed, following by the demonstration of extending potentials.