Tanzania is known for its huge power generation potential. Our Correspondent Michael Haonga spoke to the Director General of the Rufiji Basin Development Authority (RUBADA), Aloyce Masanja, who cited the case of Stiegler's Gorge as one of the potential sources of hydro-power which once fully put into use, could improve the country’s socio-economic wellbeing...Excerpts:
QUESTION: Kindly give an overview of the much orchestrated Stiegler's Gorge multi purpose project in Rufiji River Basin.
Answer: First, it should be noted that the Rufiji River Basin (RRB) in which the Stiegler's Gorge Multi-Purpose Dam is located, is the largest river basin in the country covering an area of about 177,000 square kilometres. It extends some 700 km from Mbeya in the west to the Indian Ocean with land elevation ranging from 0 to 3000m above sea level.
Q: Could you enlighten our readers as to why the name Stiegler's Gorge is given to the project?
A: This is to remember Dr. Stiegler Gorge who was killed by an elephant in 1907 while exploring the Rufiji River.
Q: And what is RUBADA?
A: Historically, RUBADA was established in 1975 by an Act of Parliament to promote and regulate development in the Rufiji Basin including the generation and supply of electricity. As it might be remembered, right from its establishment RUBADA has been predominantly engaged in planning of the Stiegler's Gorge Multi Purpose dam project.
During the planning, in 1982 and after failure of the Stiegler's Gorge to be implemented, RUBADA commissioned a study of hydropower potentials in the Rufiji Basin - Hydropower Master Plan and was completed in 1984. The Rufiji Basin Power Master Plan identified eight hydropower potentials and ranked them according to priorities.
Q: What are the potentials?
A: The following are the hydropower potentials with installed capacities in brackets -Ruhidji (685MW), Mnyera (485MW) Kihansi (240MW), Mpanga (165mw), Iringa (80MW), Lukose (130MW), Kilombero (Kingenenas and Shughuli- Falls (464MW), and Stiegler's Gorge (2,200MW). Only Stiegler's Gorge was studied up to feasibility study.
Q: What makes up the Rufiji River ?
A: Rufiji River is made up of the following tributaries; Great Ruaha -15 percent (84,000sg.km Catchment), Liweu 18 percent (26,000sq.km catchment) and Lower Rufiji 5 percent (27,000 Sq.km catchment) these are proportion of total run of off at Stiegler's Gorge.
Q: What is the hydropower potential of the project?
A: At the Stiegler's Gorge, a 130m gravity arch dam can be constructed in phases according to power needs. The total capacity is 2,1000MW and four phases were proposed. Phase 1 -300MW, Phase 11 -600MW, Phase 111- 300MW and Phase 1V -900MW. The cost of the energy to be produced is estimated to be as low as 2US c/k Wh per kwh and in the context of East African Power Pool, Tanzania has a comparative advantage over its neighbours when this project is finally developed.
Q: What are some of the advantages of the Stiegler's Gorge?
A: The project will provide flood control down stream where at present a major flood exceeding 2500M3/S can occur once in a period of three years and usually occurs in March and April. The dam once constructed will eliminate these damaging floods and simultaneously allow passage of water that is beneficial to agriculture flora and fauna and other downstream needs.
Q: What about agriculture?
A: The dam once constructed will have impact on agricultural development downstream where the Rufiji has formed a flood plain some 170 kilometers long and varying width between 7 and 30 kilometers. The soils of the flood plain are generally fertile and an area of some 80,000 hectares has been identified as suitable for irrigation. When at full development, some 450,000 hectares of paddy, 7,000 tons of maize and 3,000 tons of cotton can be grown in addition to facilitating vegetables to be grown commercially at large scale.
Q: Any other advantages?
A: Yes ranging from water supply facilitation, boosting up tourism and fisheries. With regard to water supply, a dam once constructed will create a permanent reservoir with total storage capacity of 34,000million cubic meters covering surface area of 1,2000 Sg.Km. The reservoir at the Stiegler's Gorge is a potential permanent reliable source of water to Dar es Salaam city.
Q: What about tourism?
A: The gorge is in Selous Game Reserve, which is the widest game reserve in the world containing some 750,000 animals of numerous types. Tourism in the Selous has hitherto been hindered by poor access. The 120 KM long access road from Chalinze to Stiegler's Gorge will open up this area as part of Southern Tourism Circuit development area with the Gorge itself attracting various tourist activities in the area.
Q: And fisheries?
A: The 1,200 Km2 reservoir to be created after construction of the dam will be a habitat for fish and fishery development ranging from long average yield of fish to an estimate of 3,700 tons extending to 20,000 tons at peak period in the early years with the predominant fish species being Tilapia.
Q: What is its viability?
A: Well, the economic assessment indicates that construction of the Stiegler"s Gorge was the cheapest option. In 1980 the study indicated positive economic returns taking into account power export option to neighbouring countries too.
Q: What is the cost involved?
A: In 1982 it was determined that the capital requirement for the power project was about USD1,400million with the current being at USD2bn. A high proportion of equity will be needed, let alone the fact that at 6.5/kw the project will realize profit some 12 years after commissioning of the first phase. It is also held that Rufiji River Basin has immense potentials in hydropower development in the country if exploited, and can be a source of cheap and reliable energy as well as being among existing hydropower potential in Rufiji Basin, the Stiegler"s Gorge is of the highest priority development in the country.
Q: Any latest thinking on the Stiegler"s Gorge?
A: In 2003, the fourth government decided to include Stiegler"s Gorge in its development manifesto with the Infrastructure Development Finance (IDF) of South Africa showing interest in implementing the project. They focused on Hydropower only with limited capacity of producing 900MW. In 2007, the project development was put on hold by the Government.
In July 2010, the President of Brazil visited Tanzania and made a promise to implement the Stiegler"s Gorge project. In Sept 2010, a delegation led by the Minister for Foreign Affairs, Benard Membe visited Brazil as a follow up and in October 2011, a delegation led by Prime Minister Mizengo Pinda visited Brazil as further follow up culminating into what one may call current thinking.
The current thinking is characterized by the possibility that the design of the dam may change calling for new studies to be needed and that financing options could include EPC, PPP or IPP as well as possible integration with other sectors such as water supply, irrigation, tourism, fisheries due to their importance.
Q: Any foreseeable challenges?
A: Yes. They include possibilities and implications of integration with key related sectors such as - water, agriculture, energy, tourism, and fisheries. There is also the aspect of definition of the role of the government like infrastructure development as well as institutional capacity building for RUBADA in terms of human, financial and materials resources. There are also matters pertaining to the roles of other related stakeholder institutions such as TANESCO, Rufiji River Basin Water Oddice, ministries, local government authorities as well as consideration of Tanzania commitments to International Conventions like Ramsar, World Heritage, Biodiversity as well as implications on legal framework - RUBADA Act, No, 5 of 1975.
Q: What can you say is your way forward?
A: I could say that the way forward entails capacity building for RUBADA and the role of other stakeholders. This would also entail government role and commitment among others.