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Post by onlyMark on Dec 29, 2016 20:23:52 GMT
Before independence, Zambia, Zimbabwe and Malawi were called Northern and Southern Rhodesia and Nyasaland, and ruled by the British. To be able to produce enough power for the rising populations and industry it was decided to build a hydroelectric dam on one of the great rivers of the African continent, the Zambezi. Construction began in the late 1950's by an Italian consortium called Imprasit and completed in 1958 when the final sluice gates were closed and the dam began to fill. It took a further five years for the maximum level to be reached. Plus the death of 86 workers in the process – around 18 of whom are entombed within the dam's cement. The resultant body of water behind the dam became so large that it can have its own climate and has affected seismic readings. It is reputed to be four times as large as that of the Three Gorges in China, is the largest man made reservoir by volume, is 223km long and up to 40km wide. The dam wall itself, though sturdy, is not so impressive but due to its carefully chosen location it has managed to trap an extremely large amount of water. The dam wall is located as per the map and the lake/reservoir is self apparent –
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Post by onlyMark on Dec 29, 2016 20:24:39 GMT
It was built on the site of an existing gorge and the local name Kariba/Kariva referred to a specific rock which formed a trap within the walls. The rock, now about 30m or so below the surface, was the home of the river god Nyaminyami who caused anyone who ventured near to be sucked down for ever into the depths of the river. As usual whenever a dam is built it tends to displace large numbers of people who originally settled in the rich lands now to be covered. These here are called the Batonga people or tribe. It took many years of coaxing and probably threats to evict them from their ancestral lands and all sorts of promises made. It comes as no surprise that the colonial authorities and then after independence, the governments have fulfilled some of the short term and easy responsibilities, but after an initial flurry of activity, they have been left to make the most of what they can. All fifty odd thousand of them.
They were relocated and schools, clinics and infrastructure built, but these things have been left to rot and corrode away leaving only the fortunate few who ended up living on the banks of the new reservoir to eke out a living by fishing and recently, tourism. Before being filled the vegetation was strip cleared and burnt, making the lake rich in chemicals to assist in the promotion of fish growth, which seems to have worked to a certain extent. A sardine/sprat like fish called a karpenta was introduced from Lake Tanganyika which bred successfully and enough so that a commercial fishing industry has grown up around it. A local game fish, called a Tigerfish, originally in the river, also feeds quite happily on the karpenta, this resulting in a boost to tourism in and around the lake. Crocodiles, hippos, comorants and fish eagles have stayed and thrived with the occasional herd of elephants using the easy shoreline to have their sundowners.
Apart from the downside of displacing thousands of people there were two other major disadvantages with the building of the dam. One was immediately dealt with to the best of the abilities at the time, the other ongoing and leaving an enduring legacy. The second was a massive rise in water-borne infections from schistosomiasis. No more the clean fast flowing river. Now static water, and lots of it with a large 'coastline' to promote the growth of freshwater snails. Bilharzia is found in Lake Kariba, but only in certain areas. Unfortunately, it isn't possible to pinpoint its whereabouts exactly and you're unlikely to contract it whilst in deep water in the middle of the lake. I've swum there many times but always in the middle somewhere and away from the crocs and hippos. I hope anyway.
There is a growing tourist industry around the area but mainly better on the Zimbabwe side where it is a little more organised and a greater variation of lodges, boats and fishing. I've spent many a happy couple of nights on a houseboat cruising round, fully inclusive, with cooks etc to see to your every whim. This time though, because we had to pay for it ourselves, we just went for one night on shore at took a little boat so Mrs M and the kids could get a sense of how large the lake is and have a quick look at the wall.
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Post by onlyMark on Dec 29, 2016 20:25:08 GMT
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Post by onlyMark on Dec 29, 2016 20:25:50 GMT
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Post by onlyMark on Dec 29, 2016 20:27:27 GMT
I mentioned two further disadvantages of building a dam. One was the disease the other...... In Europe maybe this wouldn't be so much of a factor but in Africa, where in many places there is abundant wildlife, what do you do with all of it? When the Aswan Dam was built in Egypt all they had to contend with was a couple of broken and falling down old temples (joke) but here there were an uncountable number of animals. This is where Operation Noah tried to sort this out. Even to the small degree it was probably done, it had to be done. As the dam began to fill, it became evident that thousands of animals were being stranded on islands. Appeals were made and money raised to buy boats and equipment for their rescue and relocation. The operation would be better clarified by quoting from the following article rather than me trying to paraphrase it. "As the dam wall closed and the waters rose, milliards of large crickets, mice, rats, and the like emerged and scurried away from the encroaching waters. The skies above were blackened by swarms of birds sating themselves on the harvest. In the water the voracious tiger fish rampaged and, glutted with drowning insects, died. Many animals, notably the larger carnivores, retreated inland. Others, however, instinctively made for high ground to wait out another seasonal flood, and were trapped on temporary islands created by the unrelenting upsurge as Lake Kariba filled. Senior ranger Rupert Fothergill, Brian Hughes (an ex-fireman who could not swim) and their assistants arrived. Under-manned and under-equipped, Operation Noah had begun. They began by trying to manoeuvre the large animals into the water and shepherding them to safety. In so doing, it was revealed that many mammals could swim long distances – waterbuck a full mile and baboon 400 yards, for instance. They also discovered that hornless female buck could paddle further than the males. And they observed instances of intelligent, adaptive behaviour such as waterbuck ferrying offspring on their backs and large horned bull antelope supporting their heads on logs, or resting them on others’ backs, during their journey to safety. Others, declining the swim, were driven into the water for easier capture before being trussed and transported to shore. During this time tranquilliser darting techniques were pioneered. This was a heroic period, when a handful of men drove themselves to the verge of collapse whilst their gains were pathetically small as thousands of animals drowned or died from shock or injuries sustained during the rescue operations." www.mv-matusadona.com/the-remarkable-history-of-lake-kariba/Eventually over 6,000 animals (elephants, antelopes, rhinos, lions, leopards, zebras, warthogs, birds and snakes) were rescued but for some reason, probably just ease of logistics, most people we relocated to the Zambian side whilst most of the rescued animals to the Zimbabwean side. That's all for now.
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Post by Deleted on Dec 30, 2016 6:12:18 GMT
This clearly never got the sort of publicity that the Aswan dam did, since in my part of the world, I have never heard of it, so many thanks for all of the explanations. Of course, I imagine that one of the reasons that you have been so generous with your explanations is because you know that very few people know this story.
I imagine that there must have been at least sporadic water problems in the dry season for them to take the decision to build the dam in the first place, but did they realise how big the lake would actually become? I was curious about the resulting hydroelectric power, so I looked up the wiki and saw that quite a bit of electricity is generated and that it has caused a different set of problems... but that the Chinese are always ready to help.
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Post by onlyMark on Dec 30, 2016 7:16:55 GMT
I had heard of the operation, as you do when you get to know an area, but the internet is a wonderful thing to tease out the details you didn't know. Did they realise how big the lake would become? Good question and I will be generous and say I expect they had a good idea from surveys. It was known that when an alternative site was considered the capacity would be far less for both water and electrical generation, but it is said the environmental impact would be considerably less as well. The Chinese are playing the long game. They lend money out left right and centre and initially seem to get little back for it. I'm not sure at all what, for example, they hoped to achieve by mostly constructing the Tazara Railway and then leaving them to it (Zambia and Tanzania) to run it. It did improve China's access to copper for a while but the whole thing has ground nearly to a halt.
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Post by mossie on Dec 30, 2016 14:24:23 GMT
Thanks Mark, I vaguely remember hearing about the Kariba Dam, presumably when it was built, but had no idea of the full story or even just that it was somewhere in Africa.
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Post by onlyMark on Dec 30, 2016 14:41:19 GMT
The scene was crying out for couple of Lancaster bombers flying low at night with a couple of strangely shaped drums being dropped.
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Post by Deleted on Dec 30, 2016 14:46:01 GMT
Well, it's normal for both of you to have heard of it since it was built with British taxes.
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Post by mossie on Dec 30, 2016 15:31:33 GMT
Well, we are the dummies who dole out out taxes to all the rest of the world and neglect to look after ourselves.
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Post by Deleted on Dec 30, 2016 15:34:36 GMT
Well, France was building (?) most of West Africa at the same time.
And of course raping it for natural resources, but the British have no lessons to learn about that!
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