May 31 is National Dam Safety Awareness Day. On May 31, 1889, the South Fork Dam failed, sending a deadly rush of water and debris into the city of Johnstown, Pennsylvania. Commonly known as the Johnstown Flood, the disaster destroyed much of the city and took the lives of more than 2,200 people. Caused by human error and indifference, it is one of the worst human tragedies experienced in U.S. history.
The upcoming anniversary of another landmark, tragic dam failure echoes the need to learn lessons from history. On June 5, 1976, Teton Dam in Idaho broke, inundating over 300 square miles and killing 11 people. The flood resulted in hundreds of millions of dollars in property damage, as well as extensive environmental damages.
“It is important to understand that communities nationwide depend on dams for their life-sustaining benefits, but may be vulnerable to the risk of dam failure, particularly when dams are not properly maintained and upgraded. The fortieth anniversary of the Teton Dam Failure serves as a reminder of the real need for constant vigilance in dam safety,” said Lori Spragens, executive director of the Association of State Dam Safety Officials (ASDSO).
Faulty decision making played a leading role in these catastrophes, both of which could have been prevented with better planning, more communication, and more humility. The good news is lessons learned from Johnstown and Teton have been applied to the establishment and improvement of dam safety programs at federal and state agencies throughout the U.S. Yet lack of dam owner vigilance and awareness continues. Over 65 percent of known dams in the U.S. are owned privately. Many dams determined to be deficient (there are over 4,000 in the U.S.) are not getting the upgrades needed to improve public safety. Many times this is due to a lack of funding and understanding of the risk.
Lack of awareness also contributes enormously to a danger posed by dams: the hydraulic currents surrounding them. This year, National Dam Safety Awareness Day will focus on encouraging swimmers and boaters to remain safe around dams.
Last year, at least 25 people drowned at dam sites across the U.S., and the trend is continuing this year, with at least 13 deaths reported: in Alabama, Colorado, Iowa, Kansas, Kentucky, Tennessee, Texas, Virginia, and Wisconsin.
“Low head” dams—dams one to fifteen feet in height, usually spanning an entire river or stream—are notoriously dangerous to individuals who kayak, swim, boat, or fish near them. And they are ubiquitous. Thousands have been constructed for municipal and industrial water supply, hydropower production, irrigation, and other uses. Many date from the 1800s.
Aptly dubbed “drowning machines,” these structures produce powerful recirculating currents that trap individuals and boats. Neither swimming ability nor personal flotation devices (PFDs) are adequate protection: of 56 victims in one study, 28 were known to have worn PFDs (Tschantz, Bruce A. [2011]. “Hidden Dangers and Public Safety at Low-head Dams.” The Journal of Dam Safety, 9[1], pp. 8-17).
“Going over one of these structures would be like being caught and spun inside a giant front loading washing machine. The rotating currents keep returning whatever is caught in them to the face of the dam and then pushing them under,” said ASDSO President Jim Pawloski. “Part of what makes these dams so dangerous is that during low flow times, the water below them often appears tranquil and even inviting. And to young people especially, a low-head dam may look like a water slide. Most people just don’t know the dangers—this is why we are seeing so many deaths.”
Several federal agencies and 49 states have statutes creating dam safety programs. These programs all share a common goal of safety of dams; striving to reduce the risk of catastrophic dam failures such as the Johnstown and Teton failures. No such nationwide initiative exists, however, to address the topic of recreational safety at dams; only a few states have directly confronted the issue.
“As we mark National Dam Safety Awareness Day, let’s begin to work together to raise awareness and educate our youth about safety at dams. Spring is the beginning of the water recreation season, National Dam Safety Awareness Day can also be a vehicle for teaching our youth about the very real dangers posed by the many structures in our streams and rivers,” said Pawloski.
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