Monday, May 31, is National Dam Safety Awareness Day in the U.S. This day seeks to encourage and promote individual and community responsibility and best practices for dam safety, as well as what steps can be taken to prevent catastrophic dam failures, according to the Federal Emergency Management Agency.
Dam Safety Awareness Day was established to commemorate the failure of the South Fork Dam in Johnstown, Pennsylvania. The Johnstown disaster – on May 31, 1889 — was the worst dam failure in the history of the U.S., with over 2,200 lives lost.
There are more than 90,000 dams in the U.S. They are an extremely important part of this nation’s infrastructure and can serve several functions, including water supply for domestic, agricultural, industrial, and community use; flood control; recreation; and clean, renewable energy through hydropower.
The average age of the dams in the U.S. is 56 years. As population growth and development continues, the overall number of high-hazard-potential dams (those whose failure could cause loss of life) increases as well, with the number climbing to more than 15,000 high-hazard potential dams in 2018. More than 11,000 dams are labeled as significant hazard potential, meaning a failure would not necessarily cause a loss of life but could result in significant economic losses.
The number of high-hazard potential and significant-hazard-potential dams is increasing in part due to “hazard creep.” Hazard creep describes the growth of development (buildings, businesses, and people) moving closer to dams that were originally located in agricultural areas.
The Association of State Dam Safety Officials says investment is needed to rehabilitate deficient dams and to improve the efficacy of policies and regulatory programs that oversee dam safety programs. Upgrade or rehabilitation is necessary due to deterioration, changing technical standards, and improved techniques, as well as better understanding of the area’s precipitation conditions, increases in downstream populations, and changing land use. When a dam’s hazard classification is changed to reflect an increased hazard potential, the dam may need to be upgraded to meet an increased need for safety.