Have you heard of lake Nyos located in the Northwest Cameroon about 196 miles away from the capital Yaounde and it is just 31 miles away from Nigeria!!
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Lake Nyos is locally known as “the Bad Lake,” carries a folklore of danger, and people do say that an evil spirit emerged from the lake to kill all those who lived near it.
“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 aady dead.”
Actual words of Joseph Nkwain, who survived one of the strangest disaster of all time.
Lake Nyos was formed in what is called volcanic crater in about 400 -500 years ago. Crater lakes are usually contains very large amount of CO2 as they are formed by the volcanic activity happening miles beneath them. This gas is usually released when ever the lake water turns over.
But in the case of lake, it didn't behave like a normal crater lake, an unusual still lake was meant to release gas from time to time instead decide to store up gas. The deep waters became highly saturated with gas at the ratio of 5gallons of CO2 to 1gallon of water invariably making the lake an actual time bomb.
This time bomb took its cause exactly on the 21st of August 1986. No one can actually say what triggered it (landslide or small volcanic eruption or a small cold rain at the edge of the lake). But the aftermath was very catastrophic as the lake exploded with water rising as high as 300ft into the air. Now the problem wasn't the water rising but actually the gas which was released into the atmosphere. About 1.2 cubic kilometers of CO2 was released in roughly 20 seconds.
This massive wave of deadly gas covered the Villages near the lake with almost no chance of survival as only 6 out of 800 could survive and in nearby Nyos only six out of 800.
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Those who did survive mostly did so by quickly escaping to higher ground on motorcycles. People were killed as far as 25km away from the lake as people in there nearby villages came out at the sound of but only to find a cloud of gas and they died right at there doorsteps. Those sleeping were killed wiith there relatives not even noticing.
The dead toll was 1,746 people killed and a livestock more than 3,500 as the villages of Nyos, Kam, Cha and Subum were wiped out.
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The lake itself at the end turned from sea blue to a deep red, which was caused by iron churned up from the bottom.
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After the disaster a lot of research and works have been tried in the lake to help in degassing it. Researchers independently proposed the use of degassimg columns to be installed
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The principle with which column works will be; a pump lifting water from the bottom of the lake which is heavily saturated with CO2, until the loss of pressure begins releasing the gas from the diphasic fluid, thus making the process self-powered.
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A French team led by Michel Halbwachs where the once to feasibily demonstrate this approach on two occasions in 1992 and 1995. Then in 2001 the USA office on foreign disaster assistance funded the team on the permanent installation of these columns in the lake.
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But in 2011 Michel Halbwachs and his French team alongside the cameroonian counterparts installed two additional pipes.
After this incidents, geologists and scientists decided to check other Africa lakes to avoid re-occurance of the disaster. After the research it was found that lake kivu also in Cameroon which is 2000 times larger than lake Nyos is also supersaturated and also has the capacity to outbourst some day in the near future
In 2005 it was pointed out that by a geologist Isaac Njilah from the University of Yaounde, that the natural dam of volcanic rocks that keeps the lake waters will collapse in the near future.
This is a a result of the high erosion activities causing wearing out of the dam creating holes and pockets in the dam upper layer and water already passing through the lower layer.
It is calculated that of the dam collapses, about 1.8billion ft of water will flow down into the states of taraba and venue of Nigeria.