The question "What is the scary biggest dam in the world?" highlights two distinct characteristics: danger and sheer size, which are embodied by different dams around the globe. While no single dam holds the title for both the most "scary" (dangerous) and the absolute "biggest" across all metrics, we can identify leading examples in each category.
The World's Most Dangerous Dam: Mosul Dam
Often dubbed the "most dangerous dam in the world," the Mosul Dam in Iraq presents a significant and ongoing risk.
- Why it's "Scary": Located on the Tigris River, its foundation is built on soluble gypsum, a mineral that dissolves when exposed to water. This geological vulnerability means the dam's foundation is continuously eroding.
- The Critical Flaw: To maintain structural integrity and prevent collapse, the dam requires constant grouting – injecting cement and other materials into the foundation to fill the voids created by the dissolving gypsum. Experts have warned there are "almost certainly an unprecedented level of untreated voids in the dam's foundation," making its long-term stability highly precarious.
- Potential Catastrophe: A catastrophic failure of the Mosul Dam could unleash a devastating floodwave downriver, threatening the lives of millions of people in populous downstream cities like Mosul and Baghdad. This ongoing threat makes it a critical concern for global engineering and humanitarian organizations.
The World's Biggest Dams: A Matter of Definition
The term "biggest" for dams can refer to various measurements, including electrical generating capacity, structural volume, or height.
By Electrical Generating Capacity: Three Gorges Dam
- Overview: The Three Gorges Dam on the Yangtze River in China is the world's largest power-generating facility.
- Massive Output: It boasts an installed generating capacity of 22,500 megawatts (MW) from 32 main generators, making it an unparalleled source of hydroelectric power.
- Multipurpose Role: Beyond electricity generation, the dam plays a crucial role in flood control and improving navigation along the Yangtze River.
By Structural Volume: Syncrude Tailings Dam
- Overview: Located in Alberta, Canada, the Syncrude Tailings Dam is not a hydroelectric dam but an earth-fill embankment dam used to contain industrial waste (tailings) from oil sands extraction.
- Unmatched Volume: With an estimated structural volume of 540 million cubic meters, it is by far the largest dam by volume in the world, dwarfing even the Three Gorges Dam in terms of the sheer amount of material used in its construction.
By Height: Rogun Dam (Projected) and Nurek Dam (Current)
- Tallest (Projected): The Rogun Dam in Tajikistan, currently under construction on the Vakhsh River, is designed to be the world's tallest dam. Upon completion, it is expected to reach a staggering height of 335 meters (1,099 feet).
- Tallest (Current): Also in Tajikistan, the Nurek Dam is currently one of the tallest dams in operation, standing at 300 meters (984 feet). It serves as a vital source of hydropower for the region.
Other Notable "Biggest" Dams
- Grand Coulee Dam (USA): Located on the Columbia River, the Grand Coulee Dam was once the largest concrete structure in the world. It remains a significant producer of hydropower and provides extensive irrigation to agricultural lands in the United States.
Comparison of Major Dams
To illustrate the different facets of "biggest" and "scary," here's a comparison of these remarkable structures:
| Dam Name | Primary Characteristic | Location | Key Metric (approx.) | Description |
|---|---|---|---|---|
| Mosul Dam | Most Dangerous | Iraq | Untreated voids in foundation | Built on soluble gypsum requiring constant maintenance; poses a severe flood risk. |
| Three Gorges Dam | Largest Power Capacity | China | 22,500 MW | World's largest power station; also crucial for flood control and navigation. |
| Syncrude Tailings Dam | Largest Structural Volume | Canada | 540 million m³ | Massive earth-fill dam for industrial waste containment. |
| Rogun Dam | Tallest (Projected) | Tajikistan | 335 meters (1,099 ft) | Under construction, designed to be the world's tallest; for hydropower and irrigation. |
| Nurek Dam | Tallest (Current) | Tajikistan | 300 meters (984 ft) | Currently one of the tallest operating dams, a major source of hydropower. |
| Grand Coulee Dam | Historic Largest Concrete | USA | 16 million cubic yards of concrete | Once the world's largest concrete structure; a major hydropower and irrigation source. |
