Watch a Beaver Dam Collapse and Instantly Drain the Massive Pond It Had Built

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There have been some devasting dam collapses in human history. Most notable, perhaps, was the failure of the South Fork Dam near Johnstown, Pennsylvania in May 1889. Its collapse released 20 million tons of water, sand, and debris which flattened buildings in its path killing over 2,000 people.

However, humans did not invent dams! Beavers perfected the art of dam building a long time before we did and as this astonishing clip reveals, they also encounter structural failures. In the below footage, we get to see a beaver dam collapsing in Cook, Minnesota. It had taken the beavers seven years to create. Thankfully, no one was injured in the torrent of water that was released.

What Exactly Are Beavers?

Beavers are large rodents in the Castor genus who have webbed feet, thick fur, powerful jaws and teeth, and a flattened, scale-covered tail. There are two species of beaver. The first is Castor canadensis, the American beaver that typically weighs around 60 pounds and the second is Castor fiber, the Eurasian beaver, which can grow to around 77 pounds.

These guys have a reputation for being hard workers and always being busy. Hence the sayings ‘busy as a beaver’ and ‘eager beaver’. They also need to be near water to survive so you will find them in and around freshwater ecosystems. Look out for them in rivers, marshes, swamps, and freshwater ponds surrounded by trees and shrubs.

How Do Beavers Build Dams?

In some ways, beavers are similar to humans in that they change their environment to suit themselves. To do this, they use their sharp teeth and powerful jaws to chew through tree trunks and branches and use them to construct dams. They often place stones at the base and seal the dam on the upstream side with mud and plants. The amazing thing is that they even make the dams thicker at the bottom and with a shallow slope on the upstream side. Any engineer will tell you that this efficiently distributes the weight of the water allowing the dam to hold back huge volumes of water.

The resulting pond is not for fishing – beavers are herbivores! In fact, it provides protection from predators by creating deep water to hide in. Their homes (called lodges) can only be accessed by underwater entrances that can be used unseen by bears and wolves. They are also used for food storage!

How Large Can Beaver Dams Get?

Beaver dams can reach heights of 10 feet and extend up to 1,600 feet in length. The world’s largest beaver dam is visible from space in satellite images. It stretches almost 2,625 feet from end to end and serves as a barrier for run-off water from the Birch Mountains in the southernmost area of Wood Buffalo National Park. The dam’s actual front measures approximately 2,540 feet in length.

Is It Normal For Beaver Dams to Break?

Beavers are rather industrious animals and are thought of as nature’s ecosystem engineers for numerous reasons. Not only do they have an incredible ability to build a dam in 24 hours that is completely airtight but they are also able to create, modify, and change waterways for their own benefit. As a result of their propensity for maintaining their habitats, and the surrounding ecosystems, for long periods of time, they have a large impact on the biodiversity in their areas.

When a beaver dam break does occur, it has a huge impact on the areas surrounding it. The resulting flooding can cause extensive property damage, structural damage to roads, and significant environmental damage due to the rapid increase in the velocity of water.