In the early 80s, I watched a TV documentary - produced I think by BBC - entitled “Water Wars”. It detailed the world’s water resources and the lengths man was going to in order to secure water reserves for the future. Towns and cities in the USA were pumping water hundreds of miles, across deserts and over mountains to feed growing demand. Some came from dams and rivers, while other sources included natural aquifers of underground water. The producers claimed that future wars would not be fought over ethnicity, religion, minerals or even dwindling oil reserves, but rather over water.

 

At about the same time, I attended a talk organised by the Zambezi Society (ZAMSOC) and presented by a hydro engineer. At that time, ZAMSOC were actively lobbying government against  further dam construction on the Zambezi River - which aside from Batoka Gorge included sites at Mupata Gorge and Devil’s Gorge, and would later be very active in monitoring exploratory drilling and surveys in the valley for natural gas and oil. Proposed projects such as the Batoka Dam just below Victoria Falls, and the Mupata Gorge Dam not far up-stream from Kanyemba (which would flood Mana Pools) and Devil’s Gorge west of Lake Kariba at the confluence of the Gwayi River confluence, were high on government’s agenda, and needless to say, met with much opposition. The water engineer discussed these, as well as various damming initiatives taking place in other parts of Africa, and concluded by saying, that no matter how loud we scream and shout, or how long we kicked and fought, all these projects will one day come to pass. Simply, man needs water and while short term projects may be focused on hydroelectric generation, long term demand for drinking water would win over any opposition or argument ever put forward. Understandably so.

 

As I write, Batoka Gorge dam is set to go ahead and will be a reality within the next decade. It is the lesser of evils, but an evil nonetheless. Mupata Gorge will also likely happen once the Mana Pools area loses significance should proposed mining operations there go ahead as suggested in a recent report in Zimbabwe’s Sunday Mail. Apparently a sedimentologist and geological consultant Dr Dennis Shoko said about surveys done by Mobil in the Zambezi Valley “They worked on the structure of our basin in areas such as the Mana Pools, the Cabora Basin and Zambezi Basin. Remember we also share this basin with Mozambique, which has also discovered oil.” The government apparently plans to start drilling.

 

Indeed, natural gas to feed thermal power stations would alleviate pressure on dams needed for hydroelectricity and solve our electricity woes... but at what cost, and is it really too high considering the alternatives? Do we destroy a massive and unique wilderness like Mana with mining operations (oil can be really messy) or the Mupata Gorge dam, or do we flood a narrow gorge at a section of the Zambezi where its impacts will be less dire? This is not to say that the Batoka Dam will not have an impact. 

 

The proposed dam site is located near the Kabompo Falls, a constriction in the river canyon and when complete will rise 181 meters (one of Africa’s tallest) creating a 50 kilometer long reservoir that would flood the gorge upstream to Rapid 5, just below Victoria Falls. The  1 680 million cubic meter reservoir will cover an area of approximately 26 square kilometers. The project would drown the Zambezi’s iconic big-water rapids and devastate river-based tourism activities like kayaking and white water rafting which is reputed to employ about 700 people (on both the Zimbabwean and Zambian sides) and generates some $4 million annually. The project has been estimated to cost in the region of $6 billion, but according to a recent analysis of large-scale dam projects across the globe, the actual costs of dams are “on average 96% higher than estimated costs.” The project will take 10-13 years to complete and once in full operation will generate 1,600-megawatts split between Zambia and Zimbabwe. Zimbabwe is reported to have a power deficit of 800MW currently, so the project is unlikely to solve any problems ten years hence.

 

A significant pro for the dam is that it will not inundate a large land mass and is in a low settlement density area, minimizing the number of people that need to be resettled. However, the gorge is a habitat for a number of rare bird species, and the project is expected to have major impacts on local endangered species. Birdlife International lists the Batoka Gorge as an ‘Important Bird Area’ on the basis of its conservation importance. Four species of note breed in the gorge, including the Taita falcon (a small, agile endangered raptor). Another 34 raptor species are also found in the gorge, including rare birds of prey such as Verraux’s eagle (previously known as the black eagle).  This loss is significant but is it acceptable when compared to the loss of Mana Pools?

 

Many argue that the flooding of that section of the river will destroy significant tourism appeal, without offering much future opportunity in return, and that it is unclear how surrounding communities would benefit, if at all, as few are linked into the national power grid. I would argue that a 50km dam, of a unique formation as the gorge will provide, would more than compensate with other water-borne tourism activities in the future. Some argue it will not offer any significant fishing opportunities due to its depth though it is expected that certain species will indeed find a niche in the dam, and while they may not be prime as far as us hardened Zambezi anglers go, species like Niloticus, vundu and the like may well provide a prime attraction for visiting anglers. Access to the water in the gorge for both tourism and utilisation would be significantly easier, and offer many opportunities along the river. At present, it is 1000 feet below ground level and unless you have a bent for rafting, of little use to the mainstream populace. I have no desire to raft - aside from being dangerous (relative to my usual activities) one risks heart failure getting in and out of the gorge, but man would I - and likely many more thousands of others - love to get on that section with a boat and fishing rod. 

 

Indeed, there are many other factors to consider, not least of all the effects on the river downstream. Other impoundments have already impacted negatively, adding to degradation of coastal mangroves; reduction in freshwater and prawn fisheries, floodplain agriculture, floodplain water supply and wildlife carrying capacity; and biophysical impacts such as the down-cutting channels in the delta and reduction of the water table level. An additional dam would worsen these impacts. Added to which an extensive 2012 report on the hydrological risks to Zambezi River dams reported climate change is predicted to cause a 25 to 40 percent reduction in the river’s flow, which could significantly compromise the hydroelectric productivity of the Batoka Gorge project.

 

According to a report by International River “Harrison & Whittington (2002) carried out some climate modeling on the proposed Zambezi dams and found that the Batoka Gorge Dam is likely to lose 6-22% production due to declining rainfall as a result of a warming climate in the basin. In his 2012 report on the hydrological risks of planned Zambezi dams (Batoka included), Beilfuss reported that these dams are unlikely to deliver the expected services over their lifetime.”