Lake Nyos

Lake Level

The surface level of Lake Nyos dropped 15 to 20 cm the evening of August 21, 1986. Approximately 22,350 cubic meters of water was displaced from the lake. This displacement was caused by waves sweeping over the spillway and the exsolving of carbon dioxide from the lower layers of the Lake Nyos.

August 22, 1986
The spillway was completely dry, which concurs with observations made by locals from Upper Nyos Palace. "The water done quench, dry for stone. The water was two inches below the spillway" (Ephriam Che).

Interview: Water Level (8/22/86)
Translation: Water Level (pdf)

August 24, 1986
The water level of Lake Nyos relative to the spillway was approximately 5.0 cm below the spillway. The spillway was completely dry. This was the first day I visited Lake Nyos after the release of the carbon dioxide.

The discrepancy of the lake level from the 22nd of August to the 24th was caused by the minimal amount of rainfall for that period. See Rainfall.

August 27, 1986
The water was just barely flowing over the spillway. I could walk across the spillway getting only the soles of my shoes wet. Haroun Tazieff and François Le Guern magically appeared in a helicopter today. To put it mildly, they were quite astonished to see me at Lake Nyos.

Note the trees and vegetation around the spillway, Lake Nyos Peace Corp Party, January 25, 1986. Top and bottom. Photos by David Cook.

September 2, 1986
The water was flowing quite well over the spillway. I got the top of my shoes wet (10-25 cm), when crossing the spillway. Quite scary; very slippery 45 meter slide over the edge.

January 25, 1986
Trees to the west of the spillway. Upper Nyos Palace in the background.

March 1, 1987 Compare this photo to the January 25, 1986 photos and notice the lack of trees and vegetation to the east and west of the spillway. No question about it! A sizeable wave(s) swept over the spillway the evening of August 21, 1986.

August 24, 1986
The one meter high grass was flattened (red dots) by the wave(s) that swept over the spillway on the evening of August 21, 1986. Note: This photo was taken October 1986.