In this paper the role and importance basic problems of the crisis answer system of the flood economic damage decrease are considered. The phases of that system and estimate procedure of flood risk are defined, by using scientific methods analysis, synthesis and description. The basic aspects of the economic damage posible decrease are analysed, by using the case study example. The main importace of the flood prevention is emphasized, as a proposal for the crisis management practice. The investment importance of the flood prevention, as the economic justifiable, is emphasized, instead of answer crisis and economic demage restoration investment. The main specifications of the new approaches in the filed of of the floods defence are showed.