Tuesday, December 12, 2006

Lake Victoria Unplugged

As reported here on Sunday Lake Victoria, the source of the Nile, is at all time lows. While the news story reported it was Global Warming that was the cause I found this article from February 2006 edition of New Scientist that reports something more sinister.

Lake Victoria is drying up because it is one giant hydro-electric dam.

However unlike the reporters who did the Sunday story I at least followed up when I found this story. They published theirs without refering to past stories.

And this story does not say Global Warming is not to blame for at least some of Lake Victoria's decline, but that it is not the only reason. And research says the Dams themselves may be contributing to the increae in Green House Gases.

EAST Africa's Lake Victoria, the world's second largest freshwater lake, is being secretly drained to keep the lights on in Uganda. A report published this week says Uganda is flouting a 50-year-old international agreement designed to protect the lake's waters.

Covering nearly 70,000 square kilometres, Lake Victoria takes a big bite out of surrounding Uganda, Kenya and Tanzania. An estimated 30 million people depend on it for their livelihoods. Since 2003, however, the lake has lost 75 cubic kilometres of water, about 3 per cent of its volume, leaving international ferries stranded far from their jetties, fishing boats mired in mud, and towns running low on water.

The only outlet for Lake Victoria, which is ringed by mountains, is at Jinja in Uganda, where it forms the Victoria Nile. Until 1954, the lake emptied into the Nile over a natural rock weir, but that year British colonial engineers blasted out the weir and replaced it with the Owens Falls dam, now renamed the Nalubaale dam, which effectively transformed the lake into a giant hydroelectric reservoir.

In 2002, Uganda finished building a second hydropower complex close to the first one. Soon after its completion people began to notice the water level falling, and today the lake is at an 80-year low. In recent weeks, the operator of the two dams, the Uganda Electricity Generating Company, has blamed disruption of electricity supplies on low lake levels, ostensibly caused by the 10 to 15 per cent decline in rainfall across the lake's catchment area during the past two years.

However, it now seems that the dams themselves are as much to blame as the recent drought. Daniel Kull, a hydrologist with the UN's International Strategy for Disaster Reduction in Nairobi, Kenya, calculates that if the dams had been operated according to the agreed curve during the past two years, the drought would have caused only half the water loss actually seen. "Today's lake levels would be around 45 centimetres higher," he writes in a report released this week by the California-based environmental lobby group, International Rivers Network.




Find blog posts, photos, events and more off-site about:
, ,, ,
, , , , , , , ,

No comments: