Critical infrastructure is defined as a network including telecommunications, informationservices, energy transport (electrical lines, natural gas and oil pipes), water supply, goods and personstransportation, financial, banking and emergency response services. All these are so significant that adisequilibrium or interruption of their operation would have a disturbing effect upon the daily life.Estimating the damage done by natural hazards to certain critical infrastructure sectors is considered animportant interest topic. The main purpose of this research is the estimation of the damages generatedby floods and flash-floods on the critical infrastructure in Maramure County during 2005-2010. Thedamages analysis is based mainly on observations and quantitative data, obtained after a thoroughanalysis of literature and reports from the Ministry of Environment and Forests and the Inspectorate forEmergency Situation of Maramure County. The results of the study were alarming. The damages causedby floods during the period subjected to study reach approximately 32 million dollars, highlighting theneed for an integrated management system for critical infrastructure protection.