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Summary Of The Commonwealth Hazard Vulnerability Analysis
Pennsylvania is a large, complex state. With more than 12 million citizens living in a blend of urban and rural settings, a diverse industrial and agricultural based economy, a sophisticated network of intra and inter-state highways, modern rail and air transportation centers, and state-of-the-art medical, communications and educational facilities, it is essential that coordinated steps be taken to protect against the occurrence and impacts of natural and man-made disasters.
The first step in coordinating emergency management efforts is to develop a common understanding of all hazards and our vulnerabilities to each. This is necessary in order that appropriate action can be taken to reduce the chance of hazards becoming disasters, minimize the impact when they do occur and to expedite the recovery.
The purpose of a hazard vulnerability analysis is to:
Develop awareness among emergency service agencies, public officials and the public of the major hazards existing in the Commonwealth.

Encourage cooperative management of emergency situations based on a common understanding of hazards and their impact.
Enhance emergency and disaster response and recovery capabilities for all hazards.
Encourage plans and actions for preventive measures and effective response to preserve life and property in areas vulnerable to the effects of natural and man-made hazards.
The 11 hazards posing the greatest dangers that have occurred most frequently in the Commonwealth are: (1) transportation accidents, (2) floods, (3) fires, (4) winter storms, (5) tropical storms, tornadoes and windstorms, (6) hazardous material accidents, (7) geological incidents (earthquakes, landslides and subsidence), (8) nuclear facility accidents, (9) dam failures, (10) terrorism and (11) riots.
The most costly of all hazards, in terms of lives lost, injuries and economic loss, is transportation accidents, which have resulted in 18,855 deaths in the state in the past 20 years. During that time, there were numerous small aircraft accidents that resulted in many deaths, including the air crash over Lower Merion in 1991 that took the lives of Senator John Heinz and six other people. The worst air crash in Pennsylvania history occurred in Beaver County in 1994 when USAir Flight 427 crashed killing all 132 on-board. On September 11, 2001, United Flight 93 crashed in Somerset County when a band of terrorists commandeered the aircraft as part of a terrorist attack on this nation. Forty-five people died on that flight.
Flooding is the most frequent and damaging natural disaster that occurs throughout the Commonwealth. Many of Pennsylvania’s communities are located along waterways. This was due in part to our early reliance on water for transportation and then as an energy source for industry. Many low-lying areas were developed long before science identified these areas as flood plains. As such, homes and personal property, business and industry, and public infrastructure, such as roads, bridges, railways and public utilities may be at risk of flood related damage and loss. The immediate economic loss and community disruption from flooding is frequently compounded when flood-damaged businesses elect not to rebuild. Since 1970, there have been more than 20 presidentially declared major disasters triggered by flooding.
Fire hazards are rated the third most severe of man-caused hazards. Fires in residential, commercial or industrial areas cause the most extensive property loss. Residential fires result in the most lives lost. An average of 296 lives were lost annually between 1976 and 1995 throughout the state with the most occurring in the city of Philadelphia with an average of 86 lives lost. Wildfires also pose a significant danger in many areas of the state.
Numerous winter storms occur throughout the Commonwealth each year. While most do not cause major economic disruption or destruction, severe snowstorms and icing can endanger lives by stranding motorists, disrupting the power supply and isolating rural populations. Since 1970, severe winter storms triggered at least eight gubernatorial disaster declarations. Of that number three resulted in federal aid authorized by the president.
Tropical storms, spawned from hurricanes that have moved inland from the Atlantic and the Gulf of Mexico, have caused flood damage and human suffering in many areas of the state. Tropical Storms Hazel (1954), Diane (1955), Agnes (1972) and Eloise (1975), Juan (1985), Floyd (1999) and Allison (2001) caused widespread flooding that threatened or claimed lives and ravaged public and private property.
Tornadoes and windstorms, which occur more frequently, can also be very deadly. In the past 20 years, there have been 11 verified tornadoes and two high windstorms. Of the former, three resulted in the major disaster declarations issued by the governor and president.
The constant increase in the production, transportation, storage and use of hazardous materials within and across the state poses one of the greatest threats to the health and safety of Pennsylvanians. Although there has never been a major hazardous material accident in the state, there is the possibility that an incident as serious as the cyanide release at the Union Carbide plant in Bhopal, India in 1984, which took the lives of 3,800 people, could occur in the Commonwealth. The control of hazardous materials is one of the most serious problems facing Pennsylvania.
Geological incidents in the state, such as earthquakes, landslides and subsidence, have caused relatively minor damage and have not been a threat to human life in most areas of the in Commonwealth. However, in certain areas, landslides and subsidence have resulted in considerable damage to public and private property. Records indicate that there have been at least 12 earthquakes, most occurring in Southeastern Pennsylvania. Most were of minor intensity. The largest recorded Pennsylvania earthquake occurred about 15 miles from Sharon in Northwestern Pennsylvania on September 25, 1998. The earthquake measured 5.2 on the Richter scale and was felt over approximately 200,000 square kilometers in the northern United States and southern Canada.
The worst fixed nuclear facility accident in U.S. history occurred in Pennsylvania in March 1979 at the Three Mile Island Nuclear Generating Station. Previously, there were minimal requirements for offsite emergency planning. Following the accident, the federal licensing process was changed and now requires that comprehensive, coordinated, implementable and exercised plans be developed for the state, counties and municipalities to assure the safety of the population. Despite the knowledge gained since then, there is the potential for a similar accident to occur again at one of the five nuclear generating facilities in the Commonwealth. This threat of an incident at a nuclear generating station was compounded following the terrorist attack on this nation on September 11, 2001.
Dam failures pose a serious threat to many communities located downstream from major dams. The worst dam failure to occur in the state resulted in the Johnstown flood of 1889, which claimed 2,100 lives. Other dam failures included: Jeanette in Westmoreland County in 1903 resulting in the loss of 23 lives; Austin in Potter County in 1911 resulting in the loss of 77 lives, and the Johnstown area of Cambria County in 1977 when seven dams failed contributing to the 85 lives lost during a major flood.
The events and subsequent impact of the September 11, 2001 terrorist attack on this nation clearly established the potential that terrorism is a real threat to Pennsylvania communities. The threat of attack using convention explosives or a Weapon of Mass Destruction (WMD), which includes radiological, biological or chemical devices, represents a challenge for every elected official and emergency manager in the state. Through the creation of the Office of Homeland Security, the federal government is working with the states to prepare this county for what had been the unthinkable threat. September 11, 2001 will be recognized as an historic benchmark in the evolution of the emergency management/preparedness program is this nation.
Pennsylvania has limited experience with disasters related to riots. However, modern day riots in this nation have resulted in extensive property losses due to vandalism and loss of human life. Community disturbances are possible as witnessed by the riots in Philadelphia in 1964, the Watts section of Los Angles in 1965 and south central Los Angles in 1992. More recently, the prison riot in October 1989 at the Camp Hill Correctional facility is an example of what can happen when personal/community unrest comes in conflict with lawful authority.
Knowledge and understanding about the hazards that exist and the vulnerable areas of the Commonwealth is a fundamental requirement for emergency planning. In essence, hazards vulnerability analysis is an attempt, prior to the actual occurrence of a crisis, to provide a basis for determining the demands on emergency services and other resources that could occur. It is also an important tool in assessing the need to improve the Commonwealth's response. While all the demands of a disaster situation cannot be anticipated, by being aware of the areas, major facilities and numbers of persons that may be vulnerable to each type of hazard, effective preventive measures can be explored and a coordinated disaster response plan can be developed.
The key to preparedness lies in pre-emergency cooperation among the various levels of government. This teamwork, in turn, depends upon community leadership, governmental support, citizen participation and the development of effective plans and operational systems. The need for effective leadership in emergency preparedness is paramount. The law assigns primary responsibility for emergency preparedness and response to elected officials at every level. Their understanding, direct support and involvement are essential, before, as well as during, emergencies.
The emergency management/preparedness program in Pennsylvania is based on a partnership that includes government at all levels, business and industry, the private sector and our volunteers. This team is committed to the development of effective plans and procedures that call for the coordinated commitment of existing resources to address threats to public health and safety as they occur in our communities. Developing an awareness and an understanding of these potential hazards is the first step toward effective community disaster preparedness.