Ep 13. Sinkholes - Buried Alive

In season 42 of NOVA, the episode 13 named Sinkholes - Buried Alive showcases the dangers posed by sinkholes along with the potential means of mitigating it. Sinkholes are nothing new to human civilization. They have been a constant reminder of Mother Nature's wrath that lays hidden beneath the earth's crust. These gaping holes in the ground can open without any notice and swallow everything from buildings, cars, and even people.

The episode starts by displaying the catastrophic aftermath of a sinkhole that took place in Guatemala. It shows how a sinkhole, in the blink of an eye, can wipe out entire communities and crush infrastructure. From hereon, the episode explores the science and geology behind these sinkholes.

The show features Geologist David Wilshaw, who is an expert on the topic of sinkholes. He explains the various ways a sinkhole can manifest, be it natural or human-made. It is astounding to know that man-made sinkholes can be just as destructive as the natural ones. They are often the result of excessive drilling and mining. David draws attention to the role that water plays in the formation of sinkholes. Underground water sources erode soluble bedrocks, creating voids in the soil that eventually collapse. Sinkholes are also triggered by earthquakes, as they cause soil liquefaction, leading to an increase in the number of sinkholes.

David Wilshaw's analysis of sinkholes is often backed up with stunning visualizations that help the viewer understand the phenomenon better. The show features a 3D map that showcases the prevalence of sinkholes in the United States. Florida is particularly prone to sinkholes due to its geography. The land itself is formed of limestone, a rock that is highly susceptible to erosion caused by underground water.

NOVA's Sinkholes - Buried Alive combines both scientific education with thrilling visuals to show the havoc that a sinkhole can wreak. It also dives deep into the scientific instruments and technologies used for the detection and prevention of sinkholes. These include LIDAR, an advanced laser technology that maps the terrain and detects any subsurface changes. Ground Penetrating Radars (GPR), sensors, and satellite imagery are also utilized to reduce the risk of calamities such as sinkholes.

As the episode progresses, viewers learn that sinkholes pose a significant threat to humanity and will continue to increase as the earth's population continues to grow. It highlights the importance of detecting sinkholes, as mitigation measures can be taken to reduce the risk to human life and property. The show also emphasizes the need for more scientific and technological innovations to combat sinkholes, which remain a major natural hazard. Examples of such measures are the use of polymer injections to strengthen the soil, and ground densification techniques to fill voids.

The episode concludes on a hopeful note, showcasing the success story of a small town in Kentucky that was severely affected by sinkholes. In collaboration with geologists and scientists, the town was able to conduct comprehensive testing of the soil and install various mitigation measures. These efforts have effectively reduced the threats posed by sinkholes in their locality.

NOVA's Sinkholes - Buried Alive is an informative episode that manages to strike the right balance between science and entertainment. It presents the science of sinkholes in a captivating manner and showcases the devastation they can cause. The underlying message of the episode is clear: sinkholes are a natural threat that can be mitigated with the right mix of scientific knowledge and effective measures.