Our Lakes, Our Future. Item Type Other Authors Chege, David Mathea Download date 28/09/2021 19:41:41 Link to Item http://hdl.handle.net/1834/6894 13th World Lake Conference International Lake Environment Committee Foundation Websites: http//www.ilec.org http//www.chinalakes.org November 1 – 5, 2009 Wahun, China Session Paper Topic OUR LAKES, OUR FUTURE. By CHEGE DAVID MATHEA REG. NO.: WLC08111423317 P. O. Box 312-00902 Kikuyu, Kenya Tel: +254202397454 Cell +254722699673 E-mail: [email protected] Submitted on 25th March 2009 via e-mail. 13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009 CONTENTS PAGE OUR LAKES, OUR FUTURE ABSTRACT.................................................................................. 3 LAKE VICTORIA.......................................................................... 7 LAKE NAKURU ........................................................................... 8 LAKE TURKANA ......................................................................... 10 LAKE MAGADI ............................................................................ 11 LAKE NAIVASHA........................................................................ 12 LAKE BARINGO.......................................................................... 13 LAKE BOGORIA.......................................................................... 15 LAKE ELMENTEITA.................................................................... 16 LAKE KAMNAROK ..................................................................... 17 LAKE LOGIPI............................................................................... 17 IMPACT OF HUMAN ACTIVITY ON OUR LAKES..................... 19 CONCLUSION THE WAY FORWARD TOWARDS THE FUTURE ..................... 23 REFERENCE ............................................................................... 25 Chege David Mathea Reg No: WLC0811142317 Page 2 13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009 OUR LAKES, OUR FUTURE. ABSTRACT The Africa continent is endowed with many lakes. There are two categories of lakes; those that form inland drainage, most of which are salty e.g. Okavango in Botswana and Shots in the Atlas mountains, and those drained by rivers which are mainly fresh water e.g. L. Victoria drained by R. Nile and L. Ngami by R. Zaire. African lakes are categorised according to their formation. Rift Valley lakes were formed when the floor of the valley was filled with water. Most of these lakes are long, narrow and deep with steep cliff-like edges. They are mostly salty due to their inland drainage. They do not have an outlet to the sea except L. Tanganyika drained by R. Lukuya during the wet season, L. Malawi by R. Shire and L. Naivasha which has an Underground outlet. Warping lakes were formed by the down warping of the ancient plateau. The depression so formed was later filled with water to form lakes. Examples include L. Victoria in East Africa, L. Kyoga in Uganda and L. Chad in Chad. Volcanic crater lakes were formed through volcanic activities. When the volcanoes erupted, the lava cooled inside a vent and a depression formed due to the subsidence of lava. This later filled with water to form a crater lake e.g. Ngorongoro crater in Tanzania. Deposition lakes are mainly ox-bow lakes formed at the old stage of the river before the mouth. Once a pronounced meander is separated from the main steam by deposition and erosion, an ox-bow lake is formed. Examples include L. Narugi on R. Tana in Kenya and L. Kilombero in Tanzania. Glacial lakes were formed in depressions or basins resulting from glacial erosion as huge blocks of ice glide down the mountain side. They are known as corries or tarns e.g. the Teleki Tarn on Mt. Kenya. Chege David Mathea Reg No: WLC0811142317 Page 3 13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009 Wind eroded lakes are found in huge depressions created by wind erosion in the desert sands. Once the water table is reached the depressions fill with water. Due to excessive evaporation, the lakes turn into muddy swamps with small water points known as oases. An example of such desert depressions is the Quattara in Egypt. Sometimes these oases may dry up completely forming salt flats known as playas. Man-made lakes are formed as a result of damming of rivers where multi-purpose river projects have been established. They are important for production of Hydro-electric power (H.E.P), transport, fishing, irrigation and regulating flooding. Examples include L. Nasser behind the Aswan High Dam in Egypt, L. Volta behind the Akosombo Dam in Ghana and L. Kariba behind the Kariba Dam on R. Zambezi. Kenyan lakes either differ from each other or are similar due to the aspects of formation, location and human interference. Lake Victoria is one of the Great Lakes of Africa. It is 68,800 square kilometres in size, making it the continent's largest lake, the largest tropical lake in the world, and the second widest fresh water lake in the world in terms of surface area. Lake Nakuru is one of the Rift Valley soda lakes. It is a small shallow alkaline lake on the southern edge of the town of Nakuru. The lake's level dropped dramatically in the early 1990s but has since largely recovered. Lake Turkana, formerly known as Lake Rudolf, is the most northern lake in the Kenya Great Rift Valley. Its far end crosses into Ethiopia. It is the world's largest permanent desert lake and the world's largest alkaline lake. Lake Magadi is the southernmost lake in the Kenya Rift Valley. During the dry season, it is 80% covered by soda and is well known for its wading birds, including flamingos. Lake Magadi is a saline-alkaline lake, approximately 100 square kilometres in size, which lies in a graben. Lake Naivasha is a freshwater lake in Kenya, lying North-West of Nairobi, outside the town of Naivasha. It is part of the Great Rift Valley. Chege David Mathea Reg No: WLC0811142317 Page 4 13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009 The name derives from the local Maasai name Nai'posha, meaning "rough water" because of the sudden storms which can arise. Lake Baringo is the second-most northern of the Great Rift Valley lakes of Kenya with a surface area of about 130 km² and an elevation of about 970 m. The lake is fed by several rivers, El Molo, Perkerra and Ol Arabel, and has no obvious outlet; the waters are assumed to seep through lake sediments into the faulted volcanic bedrock. Lake Bogoria is a saline-alkaline lake that lies in a volcanic region in a basin south of Lake Baringo, a little north of the equator. Lake Bogoria is home, at times, to one of the world's largest populations of lesser flamingos. Lake Bogoria is shallow, about 10 m deep and is about 34 km long by 3.5 km wide, with a drainage basin of 700 km². Lake Elmenteita is derived from the Maasai word muteita, meaning "dust place", a reference to the dry and dusty quality of the area, especially between January and March. The town of Gilgil is located near the lake. In the south-to-north sequence of Rift Valley lakes, Elmenteita is located between Lake Naivasha and Lake Nakuru. Human activities have had a very big impact on our lakes. The three countries bordering Lake Victoria—Uganda, Kenya and Tanzania —have been reluctant to the idea of a tax on Nile perch exports proceeds to be applied to various measures to benefit local communities and sustain the fishery. In 2002, Uganda completed a second hydroelectric complex in the area. By 2006 the water levels in Lake Victoria had reached an 80-year low, and Daniel Kull, an independent hydrologist living in Nairobi, raised an alarm that within a year, approx. 4% of the lake would be drained! The water lily (hyacinth), a native of the tropical Americas, was introduced by Belgian colonists to Rwanda to beautify their holdings but the result has been difficulties in transportation, fishing, hydroelectric power generation and drinking water supply. The situation in Lake Nakuru is nothing better. Approximately 50,000 inhabitants of Nakuru town pour some 1.1 million gallons of partially treated sewage into the shallow, 18-square-mile lake every day. Chege David Mathea Reg No: WLC0811142317 Page 5 13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009 Similarly, to the east, south and west of Lake Naivasha is agricultural land where DDT, Dieldrin and a host of other pesticides are widely used and eventually reach lake. According to scientists; they may soon reach levels that could wipe out much of the aquatic life. The way forward towards the future is that Kenyans have resolved to embark on measures to ensure conservation of our lakes for sustainable utilization in the future such as protection of the habitat globally, increased awareness and understanding of environmental conservation, Development of replicable models, improved collaboration, empowered local communities, protection of endangered habitats and improved capacity among all stakeholders. Chege David Mathea Reg No: WLC0811142317 Page 6 13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009 LAKE VICTORIA Lake Victoria or Victoria Nyanza (also known as Ukerewe and Nalubaale) is one of the Great Lakes of Africa. It is 68,800 square kilometres in size, making it the continent's largest lake, the largest tropical lake in the world, and the second widest fresh water lake in the world in terms of surface area. Being relatively shallow for its size (with a maximum depth of 84 m and a mean depth of 40 m) Lake Victoria ranks as the seventh largest freshwater lake by volume, containing 2,750 cubic kilometres of water. It is the source of the longest branch of the River Nile, the White Nile, and has a water catchment area of 184,000 square kilometres. It is a biological hotspot with great biodiversity. The lake lies within an elevated plateau in the western part of Africa's Great Rift Valley and is subject to territorial administration by Tanzania, Uganda and Kenya. The lake has a shoreline of 3,440 km and has more than 3,000 islands, many of which are inhabited. These include the Ssese Islands in Uganda, a large group of islands in the northwest of the lake that are becoming a popular destination for tourists.