Dam Failure

The American Society of Civil Engineers gave Kentucky a D+ on dam infrastructure, which is only slightly better than the national average. The average US dam is 60 years old, and most dams in Kentucky are over 50. As of 2019, 80 dams in the state are classified as two-fold risks, meaning that they are both high hazards and in poor or unsatisfactory condition. 47% of these 80 dams received that rating partially because they cannot hold enough rain during catastrophic storms. 89% of high hazard dams in Kentucky do not have complete emergency action plans on file with the state. 74% have simplified draft plans, but these are not widely shared and have not been adopted by local officials.

There are three types of Dam Failure:

1. Structural: This common cause is responsible for nearly 30% of all dam failure in the United States. Structural failure of a dam occurs when there is a rupture in the dam or its foundation.
2. Mechanical: Refers to the failure or malfunctioning of gates, conduits, or valves.
3. Hydraulic: Occurs when the uncontrolled flow of water over the top, around, and adjacent to the dam erodes its foundation. Hydraulic failure is the cause of approximately 34% of all dam failures.

The National Performance of Dams Program (NPDP), which maintains a database of failures for all dams listed in the National Inventory of Dams, lists ten dam failures in Kentucky since 1850, none of which occurred in the Barren River Region. The Barren River Region has been fortunate not to experience a dam failure; however, the potential is still there. The Corps of Engineers and Stantec (contractor) are conducting a study on the Rochester Dam’s potential failure. The final report with proposed alternatives and cost estimates were set to be released winter 2011.

Also of concern is Wolf Creek Dam. While it is not located within the BRADD region, failure of the dam would impact eastern Monroe County. In late 2007, the Army Corps of Engineers placed the dam under a ‘high risk’ for failure designation. A new long-term solution was proposed to solve, or control, the current seepage problem which began to be implemented in 2007 and is still underway.

The probability of a dam failure in the BRADD region is low but non-zero, with likelihood influenced by dam design and age, inspection/maintenance practices, spillway capacity, operational conditions, and compounding stressors such as extreme rainfall or prolonged saturation. While most dams operate safely under routine monitoring and Emergency Action Plans, the chance of structural or operational failure rises during severe storms and when downstream development expands into potential inundation zones. Given the high-consequence nature of even rare failures, consequence-focused planning, inspections, and public alerting remain essential.

Dam failures cause flooding much different from natural flooding. A flood from a dam failure may arrive before any warning or evacuation can take place and the resulting wall-of-water makes evacuation based on limited environmental cues very problematic. The failure of large dams results in flooding with enough energy to damage or destroy residences and other structures. Dam failure can occur at any time, but is often the result of other hazards, such as flooding or earthquake.

Vulnerability to dam failure in the BRADD region encompasses the built, natural, and social environments, reflecting the widespread consequences that could follow a sudden or uncontrolled release of water. Downstream communities, transportation routes, and public infrastructure located within inundation zones are most at risk of structural damage or complete loss. The natural environment, including river corridors, wetlands, and agricultural lands, may experience severe erosion, sedimentation, and contamination from debris or hazardous materials mobilized by floodwaters. Socially, populations living or working in low-lying areas near dams—particularly those with limited access to timely warnings or evacuation routes—are especially vulnerable to injury, displacement, and economic disruption. Evaluating these vulnerabilities helps local jurisdictions strengthen emergency action plans, maintain dam inspection programs, and prioritize mitigation measures that protect lives, property, and environmental resources.

The following county summaries translate dam‐failure risk into local context by considering downstream development, mapped or likely inundation areas, lifeline infrastructure (roads, bridges, water/wastewater, power), environmental sensitivities (karst, river corridors, wetlands), and social factors such as warning access and evacuation routes. Differences in dam location, hazard classification, age/condition, and proximity to populated areas drive variation in potential consequences across the BRADD region.