As dam failures and incidents occur both nationally and internationally, there is a pressing need to understand the underlying causes of failure to help minimize such occurrences in the future. Current information on historical dam incidents is sometimes scattered, incomplete, missing, or misleading – making it difficult for owners and practitioners to easily access meaningful information that could assist them with critical design and operational decisions. If lessons learned and best practices are not effectively communicated, there is a possibility that poor practices will be repeated, and preventable incidents will not be averted.
Presented within DamFailures.org are links to individual case studies and 'lessons learned' pages that summarize historical dam incidents and failures and the valuable information gleaned from them. Each page contains background and description, photographs, videos, best practices, and other resources related to the case study or lessons learned being addressed. The content of this website encompasses a range of failure modes, dam types, and dam safety topics, including best practices regarding engineering and design practices, human factors, emergency planning and response, operation and maintenance, and regulatory issues.
The site now has over 100 studies, including nearly 70 case studies and 40 lessons learned!
Thank you to all the contributors, the ASDSO Dam Failures and Incidents Committee, and the FEMA National Dam Safety Program, which provides research funding.
Case Studies
Carsington Dam (United Kingdom, 1984)
Researcher: Michael Bennett, P.E.
Reviewer: Jerry Pascoe, P.E., G.E.
The Carsington Dam’s sliding failure in June 1984 as it neared completion resulted in neither flooding nor loss of life but represented the culmination of error-filled design and construction processes. The design team did not meet the geotechnical standard of care, failing to consider progressive shear failure, probable slip surfaces, preexisting shear planes within the core clay, and acid drainage problems (which led to four construction workers dying of CO2 poisoning). The designers also included a sliding-prone “boot” within the clay’s core. The contractor made mistakes during construction, most notably compacting the embankment material well wet of optimum, but had well-founded concerns about the design and even hired an outside consultant to investigate them. However, while the consultant validated these concerns, the designer ignored them. The resulting failure led to an extensive forensic investigation that led to improved design procedures for dams, most notably regarding the brittleness of clays, progressive failure within embankments, and finite element modeling (FEM) analyses. These collectively proved valuable in designing and constructing a replacement Carsington Dam, which stands to this day.
Abu Mansour & Al-Bilad Dams (Libya, 2023)
Researcher: Michael Bennett, P.E.
Reviewers: William Johnstone, Ph.D, P.Eng. & Paul Risher, P.E.
The Abu Mansour and Al-Bilad Dams near Derna, Libya failed on September 11th, 2023, following a rainstorm with an estimated annual probability of less than 0.1% that dumped 14 inches of rain onto the region. The resulting flash flood in the Wadi Derna riverbed overtopped both dams with several feet of water, resulting in a mammoth flood wave that killed roughly 12,000 people. Maintenance issues in both dams had been noted for decades prior to the disaster, and their spillways were undersized. However, political instability kept necessary repairs and retrofits from being made. Imprudent development practices compounded these problems. The wake of the failures has offered little hope of meaningful long-term solutions, especially given Libya’s ongoing political tumult.
Kingsley Dam (Nebraska. 1941)
Researchers: Tim Gokie, P.E. & Michael A. Drain, P.E.
Reviewer: A. Tom MacDougall, P.E.
Kingsley Dam is located on the North Platte River in western Nebraska. At 163 feet (50 m) tall and over three miles long, it is the largest dam in Nebraska. On May 1st and 2nd, 1972, a 30-hour windstorm battered and eroded the upstream face of the dam. After breaking through the upstream wave protection, waves removed large portions of the upstream shell, eventually leading to the collapse of more than 400 feet (120 m) of the parapet wall along the crest of the dam. Fearing the dam would fail, residents in the downstream town of Keystone evacuated their homes and headed for higher ground. Crews were immediately summoned to lower the reservoir and begin emergency repairs. Though the winds eventually subsided, and the dam ultimately did not fail, the incident highlights the significant damage a prolonged windstorm can inflict on an earthen dam.
