Lakes Nyos and Monoun in West Cameroons both occupy craters in a supposedly extinct volcanoe and the area , is like many volcanic regions dotted with gaseous springs. Mount Cameroon, the highest mountain in Sub-Saharan west Africa, is an active volcano
On the 21st August 1986 Lake Nyos erupted and a cloud of stifling CO2 of volcanic origin which had built up in the lake spread far and wide and fast. CO2 is very soluble in water and being heavier stays at the bottom of the lake, some event made the stratification of the lakes supersaturated layers unstable and like the release of a champgane cork , the CO2 escaped in a single event.
So massive and dense was the cloud that it killed more than 1700 people and livestock up to 25 km away. Two years previously a similar but unreported at the time,a lethal gas burst ocurrred in the nearby Lake Monoun killing 37 people.
At a UNESCO Conference on the lake Nyos disaster, in March 1987 at Yaounde J.C.Sabroux coined the event a "limnic eruption" .
A French team, led by Adelin Villevieille (then Director of the French Delegation aux Risques Majeurs) and J. C. Sabroux was inspired by the gas lift technique used at the time for extracting methane from the stratified lake Kivu at Gisenyi (Rwanda) to heat the local brewery and suggested a de-gassing of the lakes to prevent further such disasters.
This project proceeded over several years and with funding from the US Office of Foreign Disaster Assistance (OFDA). The French Embassy in Yaounde and, the Cameroonian Government the Lake Nyos project was initiated,
A degassing column set up at Lake Nyos in January-February 2001. On the 31st January a perfectly stable jet, 50 m high, soared upwards above the calm waters of Lake Nyos : the degassing of the lake had begun.
Since then extremely aggressive corrosion put all of the metal parts of the column (bolting, dolly axles, etc.) out of action. In July 2003 all these metallic components were replaced by stainless steel parts.
Since then the column has functioned perfectly (cf. images of the 50 m high jet, transmitted twice daily by satellite see above and link here ) and has brought the process of enrichment of the deep layers of the lake in dissolved gas to a halt.
A similiar project was undertaken using 3 degassing columns was inaugurated on the 18th April 2006 in the presence of Her Excellency Madame the Minister of Scientific Research and Innovation and of His Excellency the French Ambassador to Cameroon. Since that time the entire installation has functioned perfectly.
Lake Nyos is is bounded on it northern part by a narrow natural dam consisting of poorly consolidated volcanic pyroclastic rocks. If the dam happened to collapse it could lead to devastating floods which could affect a downstream area as far as Nigeria, 100 km away. A mitigation plan is under consideration involving using sensing monitors to identify strains and suggested civil engineering works to make the structure more resistant to erosion.
A website by Michel Halbwachs provides a fascinating history of the whole 20 year project. (A good history of the Lake Kivu methane project is here)
Just imagine the lunatics in Whitehall are trying to reduce CO2 emissions and here is a project designed uniquely to liberate it.
PS : Just happened to notice that Mr. Guillaume GISCARD d’ESTAING, son of former French President and General Manager of SOFEMA, met 74 year old President BIYA recently and reviewed the march past on National day May 20th. SOFEMA is Sofema is an international group providing global services organized around its core businesses : Aeronautics and Defence. SOFREM Shareholders include Dassault, Thales, EADS, Safran, nexter and DCN.
Another recent visitor was General William E. WARD, commander of AFRICOM, the unified command in charge of all American military activities in Africa, and he also got the chance to have a chat with President BIYA who has been President for 26 years. James SWAN, Assistant Under-Secretary of State for African Affairs at the United States Department of State also popped in to see him March.
Useful factoid the US Embassy in Yaounde is on Avenue Rosa Parks. the Abassador Jane garvey does not mince her words ...addressing the American Chamber of Commerce Parfait Garden Hotel, Douala, Cameroon, October 9, 2007 she said ..."I know that many people are discouraged by the slow pace of reform in Cameroon. I was disheartened to see that Cameroon fell even further—to 154—in the World Bank’s annual Doing Business report and failed to improve in Transparency International’s Corruption Perception Index. Unfortunately, as you know better than me, the private sector continues to be hamstrung by a cumbersome bureaucracy, pervasive corruption and a dilapidated infrastructure. Without improvements in this area, Cameroon will not be able to generate the growth and employment it so badly needs."
More recently on April 24, 2008 she said..."Cameroon has taken some positive steps in fighting corruption. The recent detentions of two former ministers and a half dozen other senior officials who are alleged to have stolen tens of billions of CFA from the people of Cameroon are indications of the government’s determination. "