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DAMSDams provide tremendous benefits including water supply for drinking, irrigation and industrial uses; flood control; hydroelectric power; recreation; and navigation. At the same time, dams also represent one of the greatest risks to public safety, local and regional economies, and the environment. Historically, some of the largest disasters in the U.S. have resulted from dam failures. In 1889, 2,209 lives were lost when the South Fork Dam failed above Johnstown, Pennsylvania. The 1928 St. Francis Dam failure killed more than 500. During the 1970's the Buffalo Creek, Teton and Toccoa Creek dam failures collectively cost 175 lives and over $1 billion in losses. In order to provide safe continuing service, dams require ongoing maintenance, monitoring, frequent safety inspections, and rehabilitation. Over 90% of the nation's approximately 100,000 dams are regulated by the states. In order to protect public safety, state dam safety programs must be adequately staffed and funded. Alabama and Delaware are the only two states still lacking the authority to establish dam safety programs. Many others lack the human resources to enforce regulations. Further, many dam owners, including most private dam owners who own over half of the dams, lack the resources necessary to perform dam maintenance or to make significant repairs. ConditionsLike all built structures, dams deteriorate. Lack of maintenance causes dams to be more susceptible to failure. In the past two years more than 520 dam incidents, including 21 dam failures, were reported to the National Performance of Dams Program, which collects and archives information on dam performance as reported by state and federal regulatory agencies and dam owners. Dam incidents are events such as large floods, earthquakes or inspections that alert dam safety engineers to deficiencies that threaten the safety of a dam. Due to limited state staff, many incidents are not reported, and therefore the actual number of incidents is likely to be much greater. The number of high-hazard potential dams whose failure would cause loss of human life is increasing. In 1998, states reported 9,281 high-hazard potential dams, with North Carolina having the highest number (874). In 2001, there were 9,921; the number in North Carolina has increased to 988. In 2003 there are 10,049 high-hazard dams. As downstream land development increases, so will the number of high-hazard potential dams. As these dams often require major repair to accommodate more stringent inspection, maintenance and design standards, financial support for state dam safety programs must keep pace. Even more alarming, states presently report approximately 2,600 "unsafe" dams, which have deficiencies that leave them highly susceptible to failure. This represents a 23% increase since 2001. The number of unsafe dams in North Carolina increased from 40 in 1998 to 139 in 2001. Many other states have large numbers of unsafe dams including Ohio (450), Texas (403), and Colorado (190). Eleven state agencies do not keep statistics on unsafe dams; therefore the actual number is potentially much higher. The combined effect of rapid downstream development and aging/non-compliant structures, coupled with a predicted increase in extreme events, demands fully funded and staffed state dam safety programs as well as substantial and pro-active funding for dam repairs. Funding for Dam RehabilitationSince the 1998 ASCE Report Card, Congress has passed the Small Watershed Rehabilitation Act of 2000, which authorizes $90 million over five years to assess and rehabilitate a portion of the 10,000 dams constructed by the USDA. While this law is a positive step, it is neither a comprehensive nor a permanent solution.According to preliminary results of a study by the Association of State Dam Safety Officials (ASDSO), the total investment to bring U.S. dams into safety compliance or remove those that are no longer needed tops $30 billion. Except for a handful of state programs offering low interest loans to dam owners, there are no funding sources for dam rehabilitation or repair. Private owners have the greatest need of funding. The Small Watershed Rehabilitation Act addresses less than 10% of our nation's dams; the remaining 90% demand similar attention. Implementation of the National Dam Safety ProgramSince the last ASCE Report Card, the Dam Safety and Security Act of 2002 has been implemented, reauthorizing the National Dam Safety Program. Under this program, state dam safety agencies have received grants to assist them with improving dam safety regulatory programs by procuring equipment, implementing new technology, and enabling more frequent inspections. The program also provided opportunities for continuing education to dam safety engineers and funding for research to advance the technology of investigations, construction and rehabilitation of dams.Problem AreasFew state dam safety programs are adequately funded or staffed. On average nationwide, there are 582 state-regulated dams per full-time equivalent (FTE) staff. In nine states this number exceeds 800, and six of these report over 1000 dams per FTE staff. In 1998, a Texas House Committee recommended adding 15 staff members to that state's six-member dam safety team. Today there are still only six staff members responsible for inspecting over 7200 dams. One Texas official commented that, because of inadequate staffing, some dams would not be examined for three centuries.Two states, Alabama and Delaware, still have not passed dam safety legislation. As a result, an estimated 2,000 dam structures, perhaps more, are unregulated. At last count, approximately 200 of these structures were classified as high-hazard. ASDSO estimates that over 10,000 dams avoid regulation because of special state exemptions, such as agricultural uses, regardless of size or hazard potential. These dams are not inspected and their condition and hazard potential are unknown. Policy OptionsThere is still an alarming lack of public support and education about the need for proper maintenance and repair of dams. Unless a dam fails, dam safety is not usually in the public view, although it is an issue that affects the safety of thousands of people who could be living and working in the path of a sudden, deadly flood. It is imperative that policy makers act before another human tragedy occurs. Specific recommendations supported by ASCE:
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