40 years after the Lake Nyos disaster in Cameroon

Forty years after the tragic Lake Nyos disaster in Cameroon, the area is still grappling with the aftermath. Isaac Konfor Njilah, a geologist and laboratory head, explains that the disaster caught everyone off guard with no prior warning signals. At night on August 21, 1986, the lake released a lethal cloud of carbon dioxide, suffocating people and animals as they slept.

The event occurred in Cameroon's Northwest Region, near the ancient volcanic crater of Lake Nyos, located 196 miles northwest of Yaounde. Prior to the disaster, the region's population was over 3,000, with many relying on farming and cattle ranching.

The disaster claimed around 1,700 lives and affected 3,500 livestock, making it one of the deadliest natural disasters in Cameroon's history. Following the incident, scientists from Cameroon and abroad conducted extensive investigations. They discovered that carbon dioxide from deep underground had accumulated at the lake's bottom for years, trapped beneath 656 feet of water.

Njilah describes the lake as a massive bottle of carbonated water, with carbon dioxide continuously dissolving in the lake's depths. When the balance was disturbed, the gas escaped in a rapid chain reaction, releasing a deadly cloud. Scientists believe a landslide may have triggered the release by disturbing the gas-rich waters.

Carbon dioxide is harmless at normal levels, but in high concentrations, it asphyxiates by displacing oxygen. Because it's heavier than air, it flowed downhill into nearby villages, claiming many lives in their sleep. The Nyos disaster was preceded by a similar event at Lake Monoun two years earlier, killing 37 people. Eventually, scientists concluded that the deaths were caused by a rare phenomenon called a limnic eruption, involving gas-rich deep waters suddenly rising to the surface.

Engineers installed degassing pipes in Lake Nyos to gradually release trapped carbon dioxide, making the lake safe for return. However, survivors like Tsang Emelda Njah, Emelda Njah, and Kum Samuel continue to live in fear. Njah, who was 5 years old at the time, and Samuel, 17, witnessed the horror firsthand. For Ndong Frederick Bah, the loss was deeply personal, as he was the sole survivor of his family.

Although scientists have reduced the risk of another gas release, long-term reconstruction efforts face challenges due to Cameroon's Anglophone crisis. The conflict, which erupted in 2016, has disrupted plans to rehabilitate affected communities and hindered scientific work and development projects.