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LAC article on Epupa
>
> This is from The Namibian.
>
> Epupa Versus Baynes
> That Dam Question - The Epupa Debate Part 2
>
> THIS is the second column in a series by the Legal Assistance
> Centre about the Epupa debate. The previous column gave an
> overview of the players and the feasibility process. This week's
> column looks at the first volume of the Feasibility Study, which
> is a "Strategic Summary" comparing the two potential dam sites.
> Following columns will look at some of these comparative issues in
> more detail.
>
> Comparative size
>
> The total volume of the dam at Epupa would be about 4 1/2 times
> larger than the dam at Baynes - 11,5 billion cubic meters, as
> compared to 2,6 billion cubic meters. As a point of comparison
> Namibia's largest existing dam is Hardap Dam, which contains just
> under 300 million cubic meters of water when full. So the Epupa
> dam could hold more than 38 times as much water as Hardap, while
> the Baynes dam could hold about 8 1/2 times as much.
>
> The Epupa site would flood a much larger area - 380 square
> kilometres at the high water level, compared to 57 square
> kilometres at Baynes. This means that the Epupa site would take 6
> 1/2 times as much land out of use as the Baynes site. In practical
> terms, the difference is even larger because the land at the Epupa
> site has a greater use value than the land at the Baynes site,
> being currently utilised for homes, gardens, seasonal grazing and
> access to water as well as being the location of
> culturally-important gravesites.
>
> Expanses of barren land will be exposed at both sites when the
> water level is low, with this area being about 5 times greater at
> Epupa - 22000 hectares, compared to 3900 hectares at Baynes. This
> land, which is called the "draw-down zone", will not be attractive
> or useful, but it is not considered to be environmentally critical
> in either case.
>
> Dam construction
>
> The dam walls at both sites would be made of roller-compacted
> concrete, which is why they are both referred to as "RCC" dams.
> This type of construction is cheaper than conventional concrete
> dams and has been used in a number of dams in South Africa.
>
> The appropriate structure for the dam walls is determined
> primarily by the shape of the river valley. The dam at Epupa would
> be a gravity dam. In this type of construction, the weight of the
> dam wall as it presses downward resists the pressure of the water
> behind it. The main dam wall at Baynes would be an arch-gravity
> dam, where the action of gravity is assisted by the strength of
> the wall's arched shape. The Baynes dam wall would be built in a
> deep gorge which widens out about 150 meters above the river,
> necessitating a smaller flanking wall on the right side.
>
> The main dam walls at both sites would be massive. The Epupa dam
> wall would be 163 meters high, and the one at Baynes would be 200
> meters high. To imagine this size, the Sanlam Centre, one of the
> tallest buildings on Independence Avenue in Windhoek, is just
> under 50 meters high. The dam wall at Epupa would be 590 meters
> long, and the one at Baynes 700 meters long - in other words, they
> would be both be between one half and three fourths of a kilometre
> in length.
>
> Both sites are technically feasible. The Baynes site would involve
> more challenging design issues, but these are all within the realm
> of current technology.
>
> Water and evaporation
>
> It would probably take 29 months to fill a dam at the Epupa site
> to a level that is 70% of the dam's capacity. There is a
> possibility that it would take four rainy seasons to reach this
> level, which would mean delaying the present project schedule by
> one year. On the other hand, it would probably take only nine
> months to fill a dam at the Baynes site to 70% of its capacity.
> The risk of postponement at this site is very small.
>
> Water loss through evaporation will be 8 times greater at Epupa
> than at Baynes. In fact, the amount of water lost annually through
> evaporation at Epupa would be equivalent to the amount of water
> which could supply the needs of the entire city of Windhoek for 42
> years. No cost is assigned to this immense water loss, however.
> Since no irrigation schemes or major water diversions are likely
> to be planned in the remote reaches of the Cunene River, the
> Feasibility Study counts the water loss as being of no economic
> value.
>
> The role of Gove Dam
>
> The Gove Dam is located inside Angola, upstream of Ruacana. It was
> built by the Portuguese government with South African finances. It
> was virtually finished in 1975 when the outbreak of hostilities
> prevented it from being completed in accordance with its original
> design. The dam complex suffered some war damage in 1988. A
> sabotage attempt in 1990 resulted in some cracking, while other
> flaws can be traced to faulty construction. As a result of these
> problems, the water level had to be lowered and the dam can now
> operate safely at only 40% of its full storage capacity.
>
> The primary purpose of the Gove dam is to regulate the flow of the
> Cunene for more effective hydropower generation at sites
> downstream, including Ruacana. A hydropower plant at the Epupa
> site would not be reliant on water regulation at Gove Dam because
> of the large size of its reservoir. But the energy output at the
> smaller Baynes site would be significantly reduced in times of
> drought if Gove was not functioning. It is technically possible to
> rehabilitate the Gove Dam, which would have benefits in terms of
> irrigation potential and water supply for Angola as well as
> hydropower production for both nations. Political stability in
> Angola would be crucial to this approach.
>
> Epupa Falls
>
> One significant difference between the two sites is easy to
> understand. Epupa Falls will be lost forever if a dam is built at
> the Epupa site, but preserved if the Baynes site is chosen. The
> loss of such an imposing natural feature is immeasurable, and so
> is valued at zero in the cost comparison between the two sites.
>
> Flora
>
> Flooding the Epupa site will result in a much higher loss of
> living plant material ("biomass") than the Baynes site. Decaying
> plant material releases carbon into the atmosphere, contributing
> to the worldwide "greenhouse effect" that leads to global warming.
> The amount of carbon gases which would be emitted at Epupa would
> exceed international standards for such emissions, but would still
> be relatively low in comparison to other sources of carbon. No
> cost is assigned to this negative environmental impact.
>
> If the Epupa site is chosen, the destruction of Epupa Falls will
> also lead to the loss of plants associated with the "spray zone" -
> the area around the waterfall which is affected by the spray from
> the falling water. Since the Ruacana Falls now remains dry for
> long periods, the loss of Epupa Falls will destroy the last
> significant remaining habitat of this type in Namibia. Such
> habitats are fairly rare worldwide, and limited knowledge of their
> ecology makes it difficult to assess this potential loss.
>
> Another important aspect of the potential plant loss at the Epupa
> site would be the destruction of about 6000 palm trees which are a
> source of "omarunga nuts". These nuts are a key food resource for
> the local Himba in times of drought. If the Baynes site is chosen,
> only a few of these palm trees will be lost.
>
> Fauna
>
> The most profound impact on the animal kingdom will be in respect
> of fish. Two endangered species of fish have been found at both
> sites. In addition, at the Epupa site, a new species of fish has
> been found which is endemic to the area - meaning that it is not
> known to occur anywhere else in the world. The cost comparison of
> the two sites includes the cost of a breeding programme for all
> three kinds of fish - although this begs the question in the case
> of the newly-discovered species, as there may be no other natural
> habitat in the world where the fish can survive even if they are
> successfully reproduced in an artificial environment.
>
> The human impact
>
> This factor is the most complex one, and will be the subject of
> future columns. A few of the more quantifiable impacts are
> highlighted in the study's comparison between the two sites.
>
> A dam at Epupa will result in the loss of ten times more ancestral
> graves than a dam at Baynes - 160 graves at Epupa compared to only
> 15 graves at Baynes. This loss "is highly significant and can not
> be valued in monetary terms". The Feasibility Study assigns costs
> to this item, but these represent only the costs of physically
> relocating the graves or taking other practical steps to appease
> the affected Himbas. No cost is assigned to the cultural impact on
> the affected communities.
>
> The Epupa site will flood 110 permanent dwellings, as opposed to
> 15 such dwellings at Baynes. Although the Himba are nomadic, there
> are families who are very well-established in certain areas as
> well as others who visit these areas on a regular basis. The Epupa
> site will have an impact on about 1000 "permanent users" and 5000
> "occasional users", as compared to 100 "permanent users" and 2000
> "occasional users" at Baynes. The land which will be flooded at
> Epupa is also more significant in terms of seasonal gardening and
> reserve grazing during periods of drought. A dam at Epupa will
> result in the loss of two traditional river crossings which will
> constitute a major social impact., while the Baynes dam would not
> interfere with river crossings.
>
> The Epupa site is expected to produce higher incidences of malaria
> and bilharzia (schistosomiasis), a disease caused by a parasite
> associated with still or slow-flowing water. The influx of a
> labour force from other areas will probably lead to the spread of
> sexually-transmitted diseases, including HIV which has been up to
> now absent from the local Himba communities. However this problem
> is likely to arise regardless of which site is chosen.
>
> The more general social impact is particularly hard to quantify.
> Like most cultures, Himba society is already undergoing a
> continuous process of change, but a sudden and dramatic influx of
> outsiders into the region could endanger the social equilibrium -
> a problem which will be explored further in forthcoming columns.
>
> Cost
>
> According to the Feasibility Study, the Baynes site is more
> expensive. The total cost for Baynes is US$551,52 million, as
> compared to US$539,40 for Epupa. The costs of dam construction,
> power transmission facilities and slightly longer access roads are
> the components which make Baynes more expensive. However, the
> costs of the necessary waterways and environmental mitigation are
> higher for Epupa.
>
> When the costs of the two projects are compared, it must be noted
> that some of the human costs are impossible to quantify fully. The
> financial implications of the various social and cultural factors
> are quantified in the report, but this does not capture the entire
> "cost" to the affected community or the nation. For example, how
> can one place a monetary value on the loss of human life? It may
> be possible to measure the amount the person would have earned
> during his or her lifetime, or the cost of the health care
> involved. The Feasibility Study measures the possible loss of life
> in terms of the costs of the steps which will be taken to minimise
> the negative health impacts.
>
> There are other impacts which are even harder to measure. The
> report points to a number of key factors which cannot be
> adequately valued in monetary terms: (1) the loss of Epupa Falls;
> (2) the loss of biodiversity in the form of two critically
> endangered fish species at both sites, with the additional
> endangerment of a new species of fish at the Baynes site; (3) the
> loss of ancestral graves, which will be ten times greater at the
> Epupa site; and (4) the impact on the social environment. This is
> more minor and can be mitigated at Baynes while "for the Epupa
> Project these impacts in the shape of changed identities,
> lifestyles and production systems can not be fully mitigated".
> Thus, the values which are considered to be immeasurable are all
> weighted against the Epupa option.
>
> This means that there is no objective way to decide on the
> relative merits of the two sites. In the words of the Feasibility
> Study, "the final decision will have to rest on a subjective
> valuation by decision makers and is thus in the realm of
> politics".
>
> November 21 1997
>
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Lori Pottinger, Director, Southern Africa Program,
International Rivers Network
1847 Berkeley Way, Berkeley, California 94703, USA
Tel. (510) 848 1155 Fax (510) 848 1008
http://www.irn.org
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