LARGE development projects like dams and reservoirs around Africa’s mountain areas could trigger earthquakes, volcanoes and landslides, a leading South African geologist said on Tuesday.
The effects of such natural disasters in future could be aggravated by rising populations in vulnerable areas, according Chris Hartnady, a former lecturer in Goelogical Sciences at the University of Cape Town.
”Large areas of the African continent are in unstable, tectonically active states and especially in the mountain regions” posing a ”substantial danger” to the public, said Hartnady, who was attending a UN-sponsored Mountains High Summit Conference for Africa which opened in Nairobi on Monday.
Hartnady said that although mountain areas seeemed the best places to build reservoirs or hydro-electric power projects, it had been observed that in eastern and southern Africa, the high-lying areas were usually associated with ”tectonically active belts near faults and rifts in the Earth’s crust”.
Massive pressure created by holding back millions of tons of water behind a dam or in a reservoir could lead to earth tremors as was observed at the 185-metre Katse dam on the Maluti-Drakensberg mountains of Lesotho in October 1995.
After the dam was opened, residents of the neighbouring village Mapaleng Ha started to feel earth tremors the following month.
Hartnady, now based at the Seismotectonic Consultancy in Kalk Bay, South Africa, said that while African experts were aware of the dangers posed by seismic activity, there was a need to disseminate the information to the general public.
He warned that unless urgent action was taken by governments and planning authorities, the ”economic cost of seismic and volcanic disasters” would escalate this century and hamper Africa’s efforts
at sustainable development.
Hartnady said Africa could benefit from relatively inexpensive Global Positioning and Radar Satellite technologies to expand its seismic mapping as a disaster-preparedness measure.- Sapa-AFP