Sunday 17 September 2006, by PowerNell. Tanesco (Tanzania Electric Supply Company) said in a statement yesterday: "The water level at Mtera dam has completely run down, the level as of Friday September 15, 2006 was 687.77 metres above sea level. There are only 77 centimetres remaining before the cut off level of 687.00 metres is reached. At that time power generation at Mtera will stop and shortly thereafter, the country's biggest hydropower at Kidatu will stop." (Sources: Daily News, The African).
 

... but should we worry?

 
So there is 77 centimeters left. But how serious is 77 centimetres? It is serious, but is it hopeless? In July 2006 a similar situation occurred. On July 1 there were only 51 centimeters remaining at the Mtera Dam. After 87 mm of rain during that day, the water in the reservoir rose from 687.51 to 687.62 metres the day after. That marginal increase was enough to secure the production of energy for one and a half month in case there would not be more rainfall (source: The Guardian). When 11 centimetres can guarantee one and a half month of power, then 77 centimeters should guarantee at least two months of power. But... at that time the 40MW Songas turbine at Ubungo had not broken down yet... In order to stop the power rationing the level of water in the dam should be at least 695 meters above sea level (source: The Guardian).
Related articles
 
16 September 2006, Daily News: Power cuts critical against total blackout-Tanesco
3 July 2006, Guardian: Glimmer of hope as Mtera water level rises