Visit the AfricaFocus
Country Pages

Algeria
Angola
Benin
Botswana
Burkina Faso
Burundi
Cameroon
Cape Verde
Central Afr. Rep.
Chad
Comoros
Congo (Brazzaville)
Congo (Kinshasa)
Côte d'Ivoire
Djibouti
Egypt
Equatorial Guinea
Eritrea
Ethiopia
Gabon
Gambia
Ghana
Guinea
Guinea-Bissau
Kenya
Lesotho
Liberia
Libya
Madagascar
Malawi
Mali
Mauritania
Mauritius
Morocco
Mozambique
Namibia
Niger
Nigeria
Rwanda
São Tomé
Senegal
Seychelles
Sierra Leone
Somalia
South Africa
South Sudan
Sudan
Swaziland
Tanzania
Togo
Tunisia
Uganda
Western Sahara
Zambia
Zimbabwe

Print this page

East Africa: Dams and Lake Victoria

AfricaFocus Bulletin
Feb 21, 2006 (060221)
(Reposted from sources cited below)

Editor's Note

Low water levels in Lake Victoria, at their lowest point in 50 years, are threatening the livelihood of people dependent on fishing, raising the prices of fish, and provoking shortages of water for electricity generation. And now a new report charges that the crisis is due not only to drought but also to overuse of the lake's water for power generation by existing powerplants. At the same time the Uganda government has signed a new $500 million contract for building a third power plant, on the Bujagali Falls. Environmentalists charge that the new plant is likely to have more negative effects and that the hope of providing more electricity will prove unsustainable.

This AfricaFocus Bulletin contains press releases from the International Rivers Network and the National Association of Professional Environmentalists in Uganda, as well as brief excerpts from the new report by Kenya-based hydrologist Daniel Kull.

Lake Victoria is Africa's largest freshwater lake, and one that is suffering from multiple environmental threats. See http://na.unep.net/AfricaLakes for a recently released publication on Africa's Lakes: An Atlas of Environmental Change. Among the other developments with unexpected consequences was the introduction of the Nile Perch and its devastating consequences for other fish species, as described in the recent documentary Darwin's Nightmare (http://www.darwinsnightmare.com).

++++++++++++++++++++++end editor's note+++++++++++++++++++++++

New Report Confirms Dams are Draining Lake Victoria

International Rivers Network

Press Release

9 February 2006

A new report by a Kenya-based hydrologic engineer confirms that over-releases from two dams on the Nile in Uganda are a primary cause of the severe drops in Lake Victoria in recent years. The report, Connections Between Recent Water Level Drops in Lake Victoria, Dam Operations and Drought (1), finds that about 55% of the lake's drop during 2004-05 is due to the Owen Falls dams (now known as Nalubaale and Kiira dams) releasing excessive amounts of water from the lake. The natural rock formation controlling Lake Victoria's outflow was replaced by the first Owen Falls dam in the 1950s. The second dam was built with World Bank funding in the 1990s.

The lake, which has dropped 1.2 meters since 2003, was, at the end of 2005, at its lowest level since 1951. The receding shoreline has caused serious harm to water supply systems, boat operators and farmers. It is estimated that the lake catchment supports about one-third of the total population of Kenya, Uganda and Tanzania. (2)

The new study, which analyzed recent reports produced for the Government of Uganda and other publicly available information, comes to the following conclusions: The Owen Falls dams have been releasing more water than allowed by the operating rule agreed by Uganda and Egypt. This "Agreed Curve" is intended to ensure that the releases through the dams correspond to the natural flow of the river before damming. The dam operators' permits dictate allowable flows based on this agreement. Based on the current Lake Victoria hydrology, as well as observations from the past 100+ years, the Owen Falls dams are likely over-sized. The lack of public information on dam releases, dam operations and river flows makes it difficult for independent experts to soundly judge the performance of existing and proposed hydroelectric projects on the Victoria Nile. With experts concluding that the future climate will likely involve drier conditions, lower lake levels, and lower downstream river flows, the lack of adequate stream flows will be exacerbated, making it increasingly more difficult for Victoria Nile dams to produce their projected power. This calls into question Uganda's reliance on hydropower on the Victoria Nile as its primary source of electricity.

Possible climate change must be a major consideration in the development of more dams on the Nile. As the report states, "It is unknown if Lake Victoria will recharge to the high levels and outflow experienced during 1961-2000, and if such a recharge could occur, whether it would be in the next years or only in 100 years. Viable non-hydro, or at least hydro not on the Victoria Nile, power generating alternatives must therefore be considered for Uganda." Until the recent addition of emergency fossil-fuel plants, Uganda has been almost entirely dependent upon hydropower for its electricity needs.

The World Bank insisted in the 1980s that a second dam at Owen Falls, called the Owen Falls Extension Project, was Uganda's "least-cost option," and provided funding for the second dam and repair of the original dam (3). The extension project was engineered by the Canadian firm Acres International, which based its design on hydrological analysis that was considered too optimistic by many other experts at the time. The project did not undergo an environmental impact assessment; indeed, World Bank documents stated: "Extension of the existing plant at Owen Falls will have minimal environmental impact because the project will not affect downstream hydrology or fisheries." (4)

Frank Muramuzi, of the Ugandan NGO National Association of Professional Environmentalists (NAPE), said: "This dam complex is now pulling the plug on Lake Victoria, with implications for millions. The blame is on three parties: The government for refusing to listen to any views about problems with these dams; Acres International, for suspect technical advice, and the World Bank for backing the project in the first place."

Lori Pottinger of the US group International Rivers Network said: "The amazing incompetence of the World Bank and Acres reveals the kind of hubris that fuels so many large dam projects. Africa cannot afford the Bank's brand of high-risk projects any longer." For more information:

To contact author Daniel Kull: kull_daniel@hotmail.com

In Uganda: Frank Muramuzi Executive Director, National Association of Professional Environmentalists (NAPE)
Tel: +256 41 534453 Fax: +256 41 530181
E-mail: nape@nape.or.ug Website: http://www.nape.or.ug

In California: Lori Pottinger Director, Africa Programs, International Rivers Network Tel. +510 848 1155 Fax +510 848 1008
E-mail: lori@irn.org Web: http://www.irn.org

Notes

(1) Connections Between Recent Water Level Drops in Lake Victoria, Dam Operations and Drought (released Feb. 1, 2006), by Daniel Kull. Available at http://www.irn.org.

(2) Living Lakes project, http://www.livinglakes.org/victoria/

(3) According to the World Bank Inspection Panel: "IDA has been involved in the power sector in Uganda for over 20 years and has financed several projects, beginning with emergency repairs to the Owen Falls Dam in the early 1980s. IDA financed the Power II Project in 1985 (around US$28.8 million) under which rehabilitation works were carried out for the Owen Falls Dam. In 1991, it financed the Power III Project with an original amount of US$125 million) for the construction of the Owen Falls Extension. In January 2000, it provided a Supplemental Credit to the Power III Project in the amount of about US$33 million. More recently, the Power IV Project was approved in July 2001 with a Credit of about US$62 million, which will assist in financing Power Generation Unit 14, and contingent upon economic viability, Unit 15 (40-80MW) at the Owen Falls Extension powerhouse." ( http://siteresources.worldbank.org/EXTINSPECTIONPANEL/Resources/UGREQUESTFORINSPECTION.pdf )

(4) The World Bank Staff Appraisal Report, Uganda, Third Power Project, May 29, 1991.

National Association of Professional Environmentalists, Uganda

Over the Signing of the Recent Bujagali Power Purchase

December 16, 2005

As you are already aware, the government of Uganda on 13th December this year again signed the Bujagali Dam project deal with a consortium led by Industrial Promotions Services (IPS) of Aga Khan. Just like in the case of the failed AES deal 6 years ago, the new project deal has been signed in total defiance of national standard procedures, which require that such a deal, which involves huge amounts of public financing should be presented to Parliament, thoroughly debated and either approved or disapproved. What government should have done before hurrying to sign the deal was to present it to Parliament for discussion in a transparent and accountable manner.

It is unfortunate that the parties to the said agreement say that the project will cost 500 million USD as opposed to the earlier estimates of 300m USD, and 400m USD without explaining these fluctuations in cost and where the money would come from. What is also not clear is whether the funding would be from private or public sources. Our view is that if it is the public institutions such as World Bank, European investment Bank, African Development Bank or the workers savings with the National Social Security Fund (NSSF), are used to fund the project, the Power Purchase Agreement should have been debated and approved by Parliament. However, since this did not happen, the project is illegitimate. Otherwise, the Bujagali project remains a bad project for Uganda for a number of serious problems, including the following:

1. There is no Environmental Impact Assessment (EIA) yet for the new project. What is relied on is the old AES's EIA which was done more than 10 years ago. That EIA had numerous problems that have never been resolved, and does not take into account changes to the environment (such as lower lake levels and increased erosion from deforestation) that have occurred since then.
2. The issues of affordability of electricity from the project, the cost of the dam and even its viability remain unresolved as pointed out by the Inspection Panel of the World Bank in 2002 when the project was investigated.
3. The issue of the hydrology of Lake Victoria and River Nile, which have far-reaching implications on further damming of the Nile, has not been addressed in this revived project.
4. The dam safety issues in relation to the cracking of the Owen Falls dam concrete and possible collapse of the bridge, which have big implications on the survival of Bujagali dam, are also being ignored.
5. The tourism, cultural and spiritual significance of the Bujagali falls also continue to be ignored in favour of a dam.
6. The consultation process continues to ignore key stakeholders such as the Basoga clans, the cultural and spiritual leaders, local leaders, NGOs, Tourism operators and, land owners (such as Sudhir Ruparella who intends to set up a Tourist Hotel at Bujagali falls).
7. There is no plan in place to deal with/resolve resettlement problems and issues for resettled communities, including security of land ownership, development and livelihoods, health and education needs, compensation, etc.
8. There is no Environmental Impact Assessment for the transmission line to distribute electricity from the source to the central grid. This issue has always raised a lot of concerns in the project process but it continues to be ignored.

Way Forward

1. The Bujagali project must be put on hold until the outstanding issues are resolved. Short of this, the project does not meet the standards needed to attract public funding. It cannot be the project Uganda needs to solve its energy crisis if it only serves the political interests of the times.
2. In the meantime, government should pursue expeditiously the implementation of Karuma project [an alternative hydro-power project in Northern Uganda] while at the same time allocating sufficient commitment to developing alternative energy sources such as solar, geothermal, biogas, cogeneration and small hydros.
3. We urge government and the project developer to meet the conditions of civil society organizations as stipulated in the attached document.

Signed,

Muramuzi Frank Executive Director

Connections Between Recent Water Level Drops in Lake Victoria, Dam Operations and Drought

Daniel Kull Hydrologic Engineer Nairobi, Kenya

[Excerpts only: full report, including figures and references, available at http://www.irn.org/programs/nile/pdf/060208vic.pdf]

Summary

The past 2-3 years have seen sharp decreases in Lake Victoria's water level, currently more than 1.1 m below the 10-year average. In the past year it has been claimed that the dams at Owen Falls (Nalubaale and Kiira) are responsible for a portion of the lake's drop, while others insist that the drop is due only to recent droughts. This study sought to determine what factors have contributed to what extent to recent drops in Lake Victoria. Data has for some time been kept out of the public eye, but recently released reports as well as on-line resources allowed for rough analyses of the situation. At the same time, the implications for the designs and benefits of the Owen Falls and Bujagali Dams of recent level and outflow changes of Lake Victoria, as well as past observed hydrology, was analysed.

The major conclusions of the study are:

1. Recent severe drops in Lake Victoria (2004-2005) are approximately 45% due to drought and 55% due to over-releases from the Owen Falls Dams (Nalubaale and Kiira).
2. The Owen Falls Dams have not been adhering to the Agreed Curve for operations, releasing more water than dictated.
3. Based on the current Lake Victoria hydrology, as well as observations from the past 100+ years, the Owen Falls Dams are likely over-dimensioned.
4. The current hydrology, long-term observations and non-adherence to the Agreed Curve for Owen Falls Dam operations must be considered in the cost-benefit analysis of the proposed Bujagali Dam.
5. The lack of public information on dam releases, dam operations and river flows is disturbing and makes it difficult for outsiders to soundly judge implemented and proposed hydroelectric projects on the Victoria Nile. Future climates, which will likely involve "drier conditions, lower lake levels. and lower downstream river flows" (WREM, 2005a), will exacerbate conclusions 3 and 4, making it increasingly more difficult for Victoria Nile dams to produce their projected power, and thus challenge hydropower on the Victoria Nile as a viable energy alternative for Uganda.

February, 2006

1. The Problem:

Recent Severe Drops in Lake Victoria Level Since late 2003, Lake Victoria's water level has dropped over 1.1 m from its 10-year average (figure 1) .As of December 27, 2005, it was approximately 10.69 m, reaching the lowest level since 1951 (USDA, 2005). ...

2. Nalubaale Dam: Turning Lake Victoria into a Reservoir

Since 1959, the outflow of Lake Victoria - the second largest freshwater lake in the world - has been under human control, through the Nalubaale Dam (originally called Owen Falls Dam), located at Jinja, Uganda. The construction of this hydropower dam effectively transformed Lake Victoria from a natural lake to a reservoir, controlling the lake's outflow to the Victoria Nile (which eventually becomes the White Nile. Originally, the outflow of Lake Victoria, while driven by inflow from tributaries, rainfall on the lake, and evaporation from the lake, was controlled "hydraulically" by Ripon Falls. Ripon Falls acted as a natural weir and constriction, allowing a certain flow of water to exit the lake depending on the level of water in the lake. The Nalubaale Dam submerged Ripon Falls, which were also excavated in preparation for the Dam, thus assuming hydraulic control over the lake.

3. Agreed Curve Mimics Natural Flows

An "Agreed Curve" (based on agreements in 1949, 1953 and again in 1991 between Uganda and Egypt) was developed for the operation of Nalubaale Dam to dictate how much water should be released from Lake Victoria, based on the water level in the lake, shown in Figure 2. This operating rule was developed in a way to retain the original (natural) pre-Nalubaale Dam relationship between lake level and outflow. Dam operators adjust the outflow based on a water balance of the lake computed every ten days (World Bank, 2002). ... In this way, lake inputs (direct rainfall and tributary flows) and outputs (evaporation and "natural" outflow) determine the lake level, as they would have in the natural state without the dams. ...

4. Kiira Dam: Extending the Owen Falls Hydropower Complex

Not all the water being released by Nalubaale was being utilised for hydropower production. ...The Owen Falls Extension, called Kiira, was built to utilise the "excess" water being spilled by the sluices of Nalubaale, thus generating more electricity. Work started on the Kiira project in 1993 and major construction was completed in 1999. ... the two dams now in combination control the Lake Victoria water level and outflow. ...

5. What is the Cause of Recent Severe Drops in Lake Victoria?

In order to estimate what the impacts of both drought and dam operations are on Lake Victoria's water levels, the annual water balance1 of the lake was analysed under different scenarios. ...

It can be seen that although the droughts of 2004 and 2005 contributed to the lowering of the lake level, if dam operations had adhered to the Agreed Curve, today's lake levels would be around 50 cm higher. There has obviously been an additional factor in the reduction of the lake level.

During November, 2005, combined Nalubaale and Kiira dam releases were thus about double the prescribed releases, and are again extremely close to the average estimated for 2005 (1114 m3/s) in Section 5 of this report. It is clear that at least for some of the time since Kiira has come on-line, the combined outflows from Nalubaale and Kiira have been far above that prescribed by the Agreed Curve. Dam operations have therefore no longer been mimicking natural Lake Victoria outflows. ...

7. Mixed Messages on Plans and Operations

The East African media (in Uganda and Kenya, primarily) have had conflicting messages in recent weeks about this controversy. Numerous articles have made reference to the lake level dropping because of drought. But a few articles have stated that the lake's level is being negatively affected because of the operation of the dams. For example, an article in The Sunday Vision on 4 Jan. 2006 states that "The (Study on Water Management of Lake Victoria) report heaped the blame for the continued falling water levels on the over leasing of water to generate electricity at the two existing dams, Kiira and Nalubaale" (Tenywa, 2006). In this same article, Dr. Frank Sebbowa of the Electricity Regulation Authority denied the dams were at fault, blaming instead global warming. He said: "The new dam (Kiira) is supposed to replace the old dam (Nalubaale), which has become obsolete" (Tenywa, 2006). ...

8. Disputed Hydrology

The hydrology of Lake Victoria, especially the outflow into the Victoria Nile, has long been a topic of disagreement among hydrologists and engineers. Between 1960-1964, Lake Victoria experienced a massive 2.5 m increase in lake level, which many experts have attributed to a period of excessive rainfall, but the precise cause of which is not agreed. Computed averages for lake outflow depend greatly on the period of record used. ...

9. Implications for the Owen Falls Complex

The original Kiira design and cost-benefit analysis were based on the higher average flows experienced after 1961. Acres International assumed a 99% probability for the continuation of the higher flows (thus implying a 1% probability for reversion to earlier low flows) for their investment risk analysis....

.. the original Nalubaale plant, with its expansion to 180 MW, was well designed to capture the hydroelectric potential of the Owen Falls site in a sustainable manner. Considering that the project target capacity of the Owen Falls complex is 380 MW, with so far 300 MW having been installed, it must be concluded that the complex, especially Kiira, has been over-designed. This scenario was noted in the project documents: "The only significant risk to economic feasibility would arise if low hydrologic regime flows of the magnitude of the pre-1961 streamflow data set were to occur. In this case, the extension would not be economic." (World Bank, 1991). Recent technical reports further support this conclusion: "The full installed capacity of the (existing and proposed) Kiira units (208 MW) cannot be utilized until 1137 meters lake level, which, of course, is undesirable from a lake level management standpoint." (WREM, 2005b).

10. Implications for Bujagali Dam

The prospect of the flow and thus hydropower output of Bujagali Dam meeting cost-benefit expectations is a bit more positive, as the project design appears to have been based on the full hydrologic record (World Bank and IFC, 2001). ...Bujagali was designed assuming the flow released from Lake Victoria through the Owen Falls complex would be in accordance with the Agreed Curve (World Bank and IFC, 2001). As it is clear now that the Agreed Curve is no longer being respected and the Victoria Nile flow regime has changed, the original long-term energy output assessment for Bujagali is no longer valid.

11. Conclusions

... The Agreed Curve is no longer being adhered to, and the resultant overrelease of water from Nalubaale and Kiira is contributing to the severe drop in water level in Lake Victoria. The drops in Lake Victoria threaten the future performance of the Owens Falls dams, as well as to a lesser degree the proposed Bujagali Dam. "It is clear that future climates imply drier conditions, lower lake levels. and lower downstream river flows" (WREM, 2005a). It is unknown if Lake Victoria will recharge to the high levels and outflow experienced during 1961-2000, and if such a recharge could occur, whether it would be in the next years or only in 100 years. Viable non-hydro, or at least hydro not on the Victoria Nile, power generating alternatives must therefore be considered for Uganda. ...

AfricaFocus Bulletin can be reached at africafocus@igc.org. Please write to this address to subscribe or unsubscribe to the bulletin, or to suggest material for inclusion. For more information about reposted material, please contact directly the original source mentioned. For a full archive and other resources, see http://www.africafocus.org