by Devin Jarboe

Early on the morning of August 22nd, 1986 Emmanuel Ngu Mbi began to bike from the village of Wum to his home near Lake Nyos, known as the Good Lake to the locals. Soon into his journey he began to smell something unpleasant, and then fell tired. After a pleasant nap, he continued on his way, stopping to collect a dead antelope he found along the road for food. As he pedaled deeper into the lands around his home, the world grew quiet and still. No insects buzzed, no birds sang. As he traveled, the dead animals along the road began to grow in number alarmingly. Birds, rats, insects, and eventually livestock and wildlife lie dead along and besides the roads. Reaching the outskirts of town, he hailed the first hut he saw, walking inside to ask what had happened along the road. His only answer was a still more oppressive silence – everyone in the hut lie dead. Further into town, men and women lay scattered in common areas, clothes torn from their bodies. They sat slumped in chairs, or silent in their beds. No one he saw was alive. The man leaped onto his bike and fled the scene, reporting the disaster at Lake Nyos later that day. Yet he knew only the tiniest piece of the story, for the swath of death he had made his brief journey into stretched for 14 miles around lake Nysos, and at least 1,800 deceased men, women and children filled the towns and roads within.

An accurate death total was never established, and many believe the number much higher. Villagers and visitors began burying the dead in mass graves before any official tally, and others fled into the forests and surrounding towns in fear, never to return. Twice as many livestock were slain, along with most wildlife within the fertile region. You could be forgiven for thinking some cold war weapon had been unleashed on the unfortunate locals (a popular early theory, but an incorrect one). Among the locals, many suspected the recently dead chieftain of the region had vented his displeasure at his burial rights, and punished his followers. In truth the cause was both more banal and closer to home. The good lake itself had unleashed this horror upon the locals, and the killer was among the simplest and most commonplace of the many potentially lethal things surrounding us every day – carbon dioxide.


Deep in the waters of the lake, carbon dioxide had been building up, kept neatly contained by the high pressure in the deep water. What exactly caused the upending of this fragile balance is unknown – volcanism, landslides, earthquakes and even uneven rainfall have been suggested as possibilities. Regardless the end is the same – the cold, saturated waters of the deep were displaced up and to the top of the lake, and the lower pressure allowed the gas to bubble out like so much fizz in a bottle of cola, a froth of over 300 feet high roiling the surface of the lake and escaping to silently flow into the valleys and villages surrounding it. The rich iron filled mud at the bottom turned the normally blue lake deep murky red, a sign of things to come.


On 9 pm, August 21st of 1986, it happened. Following a day of heavy rains, the evening around the lake had become calmer and the people were preparing for bed or a late dinner when they heard the rumble of the escaping gas. Many came out to investigate, while others simply remained in bed. Soon they were hit with a foul smell, and breathing became difficult. Most were dead within minutes. Some simply fell into a deeper slumber, passing out rapidly. Others, up and about, reacted to the gas aggressively, tearing at their clothes and fleeing into the night as other chemicals mixed in the cloud caused burning and itching; but they too fell rapidly. Some simply died mid conversation. Within the 14 mile killing radius, almost none survived. Some on hilltops never experienced the heavy gas, waking to a morning surrounded on all sides by the dead. Others were strong enough to survive on the edges, or upwind of the gas cloud. These fortunate few woke up to 16 hours later to find their household or entire village dead, their bodies and respiratory system damaged.


To let a survivor speak for themselves-


“I could not speak. I became unconscious. I could not open my mouth because then I smelled something terrible . . . I heard my daughter snoring in a terrible way, very abnormal . . . When crossing to my daughter’s bed . . . I collapsed and fell. I was there till nine o’clock in the morning . . . until a friend of mine came and knocked at my door . . . I was surprised to see that my trousers were red, had some stains like honey. I saw some . . . starchy mess on my body. My arms had some wounds . . . I didn’t really know how I got these wounds . . .I opened the door . . . I wanted to speak, my breath would not come out . . . My daughter was already dead . . . I went into my daughter’s bed, thinking that she was still sleeping. I slept till it was 4:30 pm. in the afternoon . . . on Friday. (Then) I managed to go over to my neighbors’ houses. They were all dead . . . I decided to leave . . . . (because) most of my family was in Wum . . . I got my motorcycle . . . A friend whose father had died left with me (for) Wum . . . As I rode . . . through Nyos I didn’t see any sign of any living thing . . . (When I got to Wum), I was unable to walk, even to talk . . . my body was completely weak.” — From A. Scarth


The disaster had wide reaching effects. Huge areas of land and crops were simply abandoned overnight, and the loss of crops and land was so significant that it led to food shortages throughout the region. The sever losses of livestock led cattle prices to jump 60% over the following months, benefiting some but only adding to the regional difficulties in providing food. Perhaps just as tragic was the handling of the refugees from the region. The country set up relocation homes for them, but these were often set up in a haphazard way, at great distances from one another and poorly supplied. Families were separated because they belonged to different ethnic groups, while other relatives were scattered across multiple relocation sites. The relocation areas were smaller, with far less suitable land for farming. 21 years after the event, the relocated populations were still poor, isolated, and lacking basic facilities like schools, hospitals and roads.


The “good lake” itself lies mostly abandoned. The government forcibly relocated those who did not relocate themselves, citing the danger the lake posed. Unlike the lakes in more temperate areas where changing temperatures constantly move CO2 up and out of the system, tropical lakes often allow the CO2 to build up in the depths, saturating at high levels until it overloads and bubbles free. In an effort to stave off further possible eruptions lakes in the region have had pipes sunk into their depths, drawing up CO2 rich water and letting it degas at the surface in hopes of lowering the deep lakes carbon load, hopefully stabilizing the waters to a safe level. Yet further lakes in Africa and elsewhere remain deeply supersaturated with gases, some thousands of times larger than lake Nysos. It may be in the end, Nysos is remembered simply as a warning of greater catastrophes to come.



Forka Leypey Mathew Fomine. “The Strange Lake Nyos CO2 Gas Disaster: Impacts and The Displacement and Return of Affected Communities.” The Australasian Journal of Disaster and Trauma Studies, 4707th ser., 2011-1, no. 1174 (2011).

Brown, David. “Scientists Hope to Quiet Cameroon’s Killer Lakes.” Seattle Times, February 01, 2000.