"Despite no consensus on definitions for these terms, experts report that emergencies, disasters and catastrophes differ on more than just scale. Each requires unique response strategies as a consequence of their impact on communities and how emergency responders and resources must be mobilized. The most challenging of events are catastrophes. Catastrophes stand apart. During catastrophes, most or all infrastructure is damaged and may be inoperable. Residents in impacted communities - including emergency responders - are unable to undertake normal roles. Large numbers of residents and responders are victims. Most or all traditional functions - including government operations - are completely or partially shut down. Local mutual aid strategies are ineffective, because of the distribution of impacts on neighboring jurisdictions and communities. The loss of water and sewer services and local law enforcement and interruptions in the supply of shelter, food and medical care create additional victims even beyond those impacted by the original event. Catastrophes require different operating procedures. The loss of functional infrastructure halts the use of traditional communication, transportation and power networks. Local responders familiar with community needs and resources often are unavailable, necessitating reliance on external responders with little knowledge of local geography, cultures and possibly languages. Resource demands far outstrip supplies, creating competition and political pressure for scarce response capacity. Reliance on an expanding circle of mutual aid networks results in far more complex management challenges to integrate disparate areas of expertise, equipment, policies and procedures, and response strategies. The scale of impacts and the number of responders involved increases errors in assessments and conflicting information regarding needs and resources. Catastrophes require regional, statewide or federal authority. The scale of impacts during catastrophes, the number of responders required, the political jurisdictions affected and the range of organizations called upon to respond, require a regional, statewide or national authority to manage. Local officials generally cannot manage catastrophic response because the authority needed to do so exceeds their jurisdiction". (Little Hoover Com., Safeguarding, 2007, 14)