Seven Forks Dam comprises of five #hydro power plants namely; Masinga ,Gitaru,Kamburu, Kindaruma & Kiambere.
Completed in 1968, Kindaruma is the first post-independence power plant.The scheme accounts for nearly 49% of hydroelectric power in Kenya. ^ZB #EnergyForTheNation
The ca. 1000 km long Tana River is the longest river in Kenya, and gives its name to the Tana River County. Its catchment covers ca. 100,000 km² and can be divided into the headwaters and the lower Tana consisting of the section downstream of Kora where the river flows for ca. 700 km through semi-arid plains. Its tributaries include the Thika, Ragati River from Mt.Kenya as well as several smaller rivers that flow only during the rainy season. The river rises in the Aberdare Mountains to the west of Nyeri. Initially it runs east before turning south around the massif of Mount Kenya. A series of hydroelectric dams (the Seven Forks Hydro Stations or the Seven Forks Scheme) has been constructed along the river. These include (in order of cascading) the Masinga Dam (commissioned in 1981 with an installed capacity of 40MW), the Kamburu Dam (1974, 94.20MW), the Gitaru Dam (1978, 225.25MW), the Kindaruma Dam (1968, 72MW) and the Kiambere Dam (1988, 168MW). en The Masinga Reservoir and the Kiambere Reservoir, created by the Masinga and Kiambere dams respectively, serve a dual purpose: hydro-electric power (HEP) generation and agricultural irrigation. The other three are used exclusively for HEP generation. A 2003 study reported that two-thirds of Kenya’s electrical needs were supplied by the series of dams along the Tana River. Many people believe this river has groundwater underneath it, but it doesn’t. The electricity is then supplied to the national grid system and distributed countrywide through a series of substations, transformers and cables.
Below the dams, the river turns north and flows along the north-south boundary between the Meru and North Kitui and Bisanadi, Kora and Rabole National Reserves. In the reserves the river turns east, and then south east. It passes through the towns of Garissa, Hola and Garsen before entering the Indian Ocean at the Ungwana Bay–Kipini area, at the end of a river delta that reaches roughly 30 km upstream from the river mouth itself It runs through a semi-arid area and irrigates the surrounding land.
Annual flow is above 5,000 million cubic meters (MCM) on average, but varies substantially both within and across years, and includes two flood seasons each year Between 1944 and 1978, average total flow (at Garissa) was 6,105 MCM, varying from only 1,789 MCM in 1949 to 13,342 MCM in 1968. During the 1982-1996 period, annual flow remained above 5,000 MCM as well. Water is drawn from the river by the following major irrigation projects: Bura Irrigation and Settlement Project, Tana Irrigation Scheme and the Tana Delta Irrigation Project.
There is growing evidence that climate change will disrupt the Tana River and its surrounding habitats
As of 2007, Kenya’s hydropower stations have had a total installed capacity of 677.3 MW.
The power stations comprise:
- the Seven Forks Hydro Stations
- the Mini Hydro Stations
- Turkwel Power Station
Seven Fork Hydro Stations
The five stations have an installed capacity of 543.2 MW. Water has been cascaded from one station to the next, taking advantage of the head created by each dam to produce power. To provide adequate flow during the dry periods, water is stored at Masinga Reservoir and released during the dry season. Two other sites along the river, Mutonga and Grand Falls were yet to be developed in 2007.
Masinga Power Station
Masinga Power Station has an installed capacity of 40 MW, and was commissioned in 1981. Two vertical Kaplan turbines drive two generators capable of generating 40 MW of power. The power generated is transmitted to Kamburu power station for transmission to Nairobi. In addition to the 40MW produced by this station, Masinga serves as a crucial reservoir, which has a capacity of 1.56 billion cubic meters of water. This reservoir is used for water regulation throughout the year. The dam occupies a surface area of 120 km².
Kamburu Power Station
Kamburu Power Station has an installed a capacity of 94.2 MW and was commissioned in 1974. Kamburu is the first underground power station in the complex. Electric power from Kamburu is conveyed to Nairobi via two 220 kV transmission lines from a primary 132 kV substation. Water is conveyed to Gitaru Power Station via a 2.9 km tailrace tunnel.
Gitaru Power Station
Gitaru Power Station has an installed capacity of 225 MW, and was commissioned in 1978 (145 MW) and 1999 (80 MW) Gitaru is the biggest power station in Kenya in terms of installed capacity. The power produced is transmitted to Kamburu 132 kV substation via two 132 kV circuits. The discharge from Gitaru Station is conveyed through a 5 km tailrace tunnel which empties into Kindaruma reservoir.
Kindaruma Power Station
Kindaruma Power Station has an installed capacity of 44 MW, and was commissioned in 1968. Kindaruma is the first station to be constructed in the Seven Forks complex. Power from Kindaruma is transmitted directly to Nairobi via a 132 kV line or to Kamburu 132 kV substation. The water is then passed down to Kiambere – the latest development in the complex.
Kiambere Power Station
Kiambere Power Station has an installed a capacity of 144 MW, and was commissioned in 1988. The reservoir’s capacity is 585 million m³. As it is currently the last dam on the Tana, the machines run mostly as base load hence the large power output. The underground powerhouse is situated 4 km away from the saddle dam where the intake structure is located. The water conveyance is by a 6m-diameter headrace tunnel.