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.

Lake Victoria is relatively young; its current basin formed only 400,000 years ago, when westward-flowing rivers were dammed by an up thrown crystal block. The lake's shallowness, limited river inflow, and large surface area relative to its volume make it vulnerable to climate changes. Cores taken from its bottom show that Lake Victoria has dried up completely three times since it formed. These drying cycles are probably related to past ice ages, which are times when precipitation declined globally. The lake last dried out 17,300 years ago, and filled again beginning 14,700 years ago; the fantastic adaptive radiation of its native cichlids has taken place in the short period of time since then.

The ecosystems of Lake Victoria and its surroundings have been badly affected by human influence. In 1954, the Nile perch was first introduced into the lake's ecosystem in an attempt to improve fishery yields of the lake. Introduction efforts intensified during the very early-1960s. The species was present in small numbers until the early to mid- 1980s, when it underwent a massive population expansion and came to dominate the fish community and ecology of the world's largest tropical lake.

Chege David Mathea Reg No: WLC0811142317 Page 7

13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009

Also introduced was the Nile tilapia, now an important food fish for local consumption. The Nile perch proved ecologically and socio-economically devastating. Together with pollution born of deforestation and overpopulation (of both people and domestic animals), the Nile perch has brought about a massive transformation in the lake's ecosystem and to the disappearance of hundreds of endemic haplochromine cichlid species. Many of these are now presumed to be entirely extinct.

Also vanished from Lake Victoria is one of two native species of tilapia, the Singidia tilapia or ngege. The ngege is superior in taste and texture to Nile tilapia, but it does not grow as fast or as large and produces fewer young. Ngege and some representatives of haplochromine diversity survive in minute swamp ponds and lakes that dot the Lake Victoria Basin. The initial good returns on Nile perch catches, at their peak delivering export revenues of several hundred million dollars a year, have diminished dramatically due to poor enforcement of fisheries regulations. The proceeds from Nile perch sales remain an important economic engine in the region, but the resulting wealth is very poorly distributed and the overall balance sheet on the Nile perch introduction to Lake Victoria is well into the red despite the enormous value of the perch landings as an export commodity.

LAKE NAKURU

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. It varies from 5 to 45 square kilometres and lies about 160 kilometres north of Nairobi. Nakuru means "Dust or Dusty Place" in Maasai language. Lake Nakuru lies within the Lake Nakuru National Park (188 km²) that was established in 1961. It started off small, only encompassing the famous lake and the surrounding mountainous vicinity. Now it has been extended to include a large part of the savannahs. The lake's abundance of algae attracts the vast quantity of flamingos that famously lines the shore. Other birds also flourish in the area, as do warthogs, baboons and other large mammals. Black and White rhinos have also been introduced.

Chege David Mathea Reg No: WLC0811142317 Page 8

13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009

Lake Nakuru National Park is best known for its thousands, sometimes millions of flamingos nesting along the shores. The surface of the shallow lake is often hardly recognizable due to the continually shifting mass of pink. The number of flamingos on the lake varies with water and food conditions and the best vantage point is from Baboon Cliff. Also of interest is an area of 188 km around the lake fenced off as a sanctuary to protect Rothschild giraffes and black rhinos.

The park has recently been enlarged partly to provide the sanctuary for the black rhino. This undertaking has necessitated a fence - to keep out poachers rather than to restrict the movement of wildlife. The park marches for 12.1 km on the south eastern boundary with the Soysambu conservancy which represents a possible future expansion of the habitat up to Lake Naivasha for the rhinos and the only remaining wildlife. The park now has more than 25 rhinoceros, one of the largest concentrations in the country, so the chances of spotting these survivors are good. There are also a number of Rothschild's giraffe, again trans-located for safety from western Kenya beginning in 1977. Waterbucks are very common and both the Kenyan species are found here. Among the predators are lions and leopards, the latter being seen much more frequently in recent times. The park also has large sized pythons that inhabit the dense woodlands, and can often be seen crossing the roads or dangling from trees.

The lake is world famous as the location of the greatest bird spectacle on earth, with myriads of fuchsia pink flamingos whose numbers are vast, often more than a million - or even two million. They feed on the abundant algae, which thrives in the warm waters. Scientists reckon that the flamingo population at Nakuru consumes about 250,000 kilos of algae per hectare of surface area per year. There are two types of flamingo species: the Lesser flamingo can be distinguished by its deep red carmine bill and pink plumage unlike the Greater, which has a bill with a black tip. The Lesser flamingos are ones that are commonly pictured in documentaries mainly because they are large in number.

The number of flamingos has been decreasing recently, perhaps due to too much human presence, pollution resulting from industrial waterworks nearby who dump waste into the waters, or simply because of changes in water quality which makes the lake temporarily inhospitable. Usually, the lake recedes during the dry season and floods during the wet season. Chege David Mathea Reg No: WLC0811142317 Page 9

13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009

In recent years, there have been wide variations between the dry and wet seasons' water levels. It's suspected that this is caused by increasing watershed land conversion to intensive crop production and urbanization, both which reduce the capacity of soils to absorb water, recharge ground waters and thus increase seasonal flooding.

Pollution and drought destroy the flamingos' food (Cyano-bacteria) or blue-green algae, causing them to migrate to the nearby Lakes, such as lakes Elmenteita, Simbi Nyaima and Bogoria. Local climate changes have also been hypothesized to contribute to the changing environmental conditions in the lake’s catchment. Recent media reports indicate increasing concern among stakeholders, as mass flamingo migrations and deaths could spell doom to the tourism industry. The flamingos feed on algae, created from their droppings mixing in the warm alkaline waters, and plankton. But flamingos are not the only avian attraction, also present are two large fish eating birds, pelicans and cormorants. Despite the tepid and alkaline waters, a diminutive fish, Tilapia grahami has flourished after being introduced in the early 1960s. The lake is rich in other birdlife. There are over 400 resident species on the lake and in the surrounding park. Thousands of both little grebes and white winged black terns are frequently seen as are stilts, avocets, ducks, and in the European winter the migrant waders. Also, a bunch of Zebra graze nearby.

LAKE TURKANA

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. By volume it is the world's fourth largest salt lake after the Caspian Sea, Lake Issyk-Kul and the (shrinking) Aral Sea. Among all lakes it ranks twentieth in size. The water is potable but not palatable. It supports a rich lacustrine wildlife. The climate is hot and very dry. The rocks of the surrounding area are predominantly volcanic. Central Island is an active volcano, emitting vapours. Outcrops and rocky shores are found on the East and South shores of the lake, while dunes, spits and flats are on the West and North, at a lower elevation.

Chege David Mathea Reg No: WLC0811142317 Page 10

13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009

On-shore and off-shore winds can be extremely strong as the lake warms and cools more slowly than the land. Sudden, violent storms are frequent. Three rivers (the Omo, Turkwel and Kerio) flow into the lake, but lacking outflow its only water loss is by evaporation. Lake volume and dimensions are variable. For example, its level fell by 10 meters between 1975 and 1993.

Due to temperature, aridity and geographic inaccessibility, the lake retains its wild character. Nile crocodiles are found in great abundance on the flats. The rocky shores are home to scorpions and carpet vipers. Although the lake and its environs have been popular for expeditions of every sort under the tutelage of guides, rangers and experienced persons, they certainly must be considered hazardous for unguided tourists.

Lake Turkana National Parks are now listed as a UNESCO World Heritage Site. Sibiloi National Park lies on the lake's eastern shore, while Central Island National Park and South Island National Park lie in the lake. Both are known for their crocodiles.

LAKE MAGADI

Lake Magadi is the southernmost lake in the Kenya Rift Valley, lying in a catchment of faulted volcanic rocks, north east of Lake Natron. 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. The lake is an example of a "saline pan". The lake water, which is dense sodium carbonate brine, precipitates vast quantities of the mineral trona (sodium sesqui-carbonate). In places, the salt is up to 40 m thick. The lake is recharged mainly by saline hot springs with temperatures up to 86°C that discharge into alkaline "lagoons" around the lake margins, there being little surface runoff in this arid region. Most hot springs lie along the north-western and southern shorelines of the lake. During the rainy season a thin layer of brine covers much of the saline pan, but this evaporates rapidly leaving a vast expanse of white salt that cracks to produce large polygons.

Chege David Mathea Reg No: WLC0811142317 Page 11

13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009

A single species of fish, a cichlid Alcolapia grahami, inhabits the hot, highly alkaline waters of this lake basin and is commonly seen in some of the hot spring pools around the shoreline where the water temperature is less than 45°C.

Lake Magadi was not always so saline. Several thousand years ago (during the late Pleistocene to mid-Holocene) the Magadi basin held a freshwater lake with many fish, whose remains are preserved in the High Magadi Beds, a series of lacustrine and volcaniclastic sediments preserved in various locations around the present shoreline. Evidence also exists for several older Pleistocene precursor lakes that were much larger than present Lake Magadi. At times, Lake Magadi and Lake Natron were united as a single larger lake.

Lake Magadi is also well known for its extensive deposits of siliceous chert. There are many varieties including bedded cherts that formed in the lake and intrusive dyke-like bodies that penetrated through overlying sediments while the silica was soft. Most famous is "Magadi-type chert", which formed from a sodium silicate mineral precursor magadiite that was discovered at Lake Magadi during the 1960s.

Magadi township lies on the lake's east shore, and is home to the Magadi Soda factory, owned by Tata India since December 2005. This factory produces soda ash, which has a range of industrial uses.

LAKE NAIVASHA

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. The name derives from the local Maasai name Nai'posha, meaning "rough water" because of the sudden storms which can arise. The lake has a surface area of 139 km², and is surrounded by a swamp which covers an area of 64 square km, but this can vary largely depending on rainfall. It is situated at an altitude of 1,884 metres (6,180 ft). The lake has an average depth of 6 m (20 ft), with the deepest area being at Crescent Island, at a maximum depth of 30 m (100 ft). Njorowa Gorge used to form the lake's outlet, but it is now high above the lake and forms the entrance to Hell's Gate National Park.

Chege David Mathea Reg No: WLC0811142317 Page 12

13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009

The lake is home to a variety of wildlife; over 400 different species of bird have been reported. There is a sizeable population of hippos in the lake. There are two smaller lakes in the vicinity of Lake Naivasha: Lake Oloiden and Lake Sonachi (a green crater lake). The Crater Lake Game Sanctuary lies nearby, while the lake shore is known for its population of European immigrants and settlers. Between 1937 and 1950 the lake was used as a landing place for flying boats on the Imperial Airways passenger and mail route from Southampton in Britain to South Africa. It linked Kisumu and Nairobi.

Floriculture forms the main industry around the lake. However, the largely unregulated use of lake water for irrigation is reducing the level of the lake and is the subject of concern in Kenya. Fishing in the lake is also another source of employment and income for the local population. The lake varies in level greatly and almost dried up entirely in the 1890s. Having refilled, water levels are now dropping again. The town of Naivasha (formerly East Nakuru) lies on the north east edge of the lake.

In 1981, the first geothermal plant for Lake Naivasha was commissioned and by 1985, a total of 45 MW of electricity was being generated in the area. The water level for Lake Naivasha reached a low level of 0.6 m depth in 1945, but the water level rose again, with minor drops, to reach a maximum depth nearly 6 m in 1968. There was another major decline of the water level in 1987, when the depth reached 225 cm above the lake bottom.

The decline of the lake water level in 1987 increased concern in the future of geothermal industry, and it was speculated that Lake Naivasha underground water might be feeding the geothermal reservoir at Olkaria. Hence, the decline in the lake water would affect the future of the geothermal industry.

LAKE BARINGO

Lake Baringo is the second-most northern of the Great Rift Valley lakes of Kenya, after Lake Turkana, 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.

Chege David Mathea Reg No: WLC0811142317 Page 13

13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009

It is one of the two freshwater lakes in the Rift Valley in Kenya, the other being Lake Naivasha. It lies off the beaten track in a hot and dusty setting and over 470 species of birds have been recorded there, occasionally including migrating flamingos.

The lake is part of the Great Rift Valley system. The Tugen Hills, an uplifted fault block of volcanic and metamorphic rocks, lies west of the lake. The Laikipia Escarpment lies to the east. Water flows into the lake from the Mau Hills and Tugen Hills. It is a critical habitat and refuge for more than 500 species of birds and fauna, some of the migratory water-bird species being significant regionally and globally. The lake also provides an invaluable habitat for seven fresh water fish species. Lake fishing is important to local social and economic development. Additionally the area is a habitat for many species of animals including the hippopotamus, crocodile and many other mammals, amphibians, reptiles and the invertebrate communities.

Fish stocks in the lake are now low and water levels have been reduced by droughts and over-irrigation. The lake is commonly turbid with sediment, partly due to intense soil erosion in the catchments, especially on the Loboi Plain south of the lake.

The lake has several small islands, the largest being Ol Kokwe Island. Ol Kokwe, an extinct volcanic centre related to Korosi volcano north of the lake, has several hot springs and fumaroles, some of which have precipitated sulphur deposits. A group of hot springs discharge along the shoreline at Soro near the north-eastern corner of the island.

Several important archaeological and palaeontological sites, some of which have yielded fossil hominoids and hominins, are present in the Miocene to Pleistocene sedimentary sequences of the Tugen Hills.

The main town near the lake is Marigat, while smaller settlements include Kampi ya Samaki and Loruk. The area is increasingly visited by tourists and is situated at the southern end of a region of Kenya inhabited largely by pastoralist ethnic groups including Ilchamus, Rendille, Turkana and Kalenjin.

Chege David Mathea Reg No: WLC0811142317 Page 14

13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009

LAKE BOGORIA

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, like Lake Nakuru, Lake Elmenteita, and Lake Magadi further south in the Rift Valley, and Lake Logipi to the north, is home at times to one of the world's largest populations of lesser flamingos. The lake is a Ramsar site and has been a protected National Reserve since November 29, 1973. 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.

Local features include the Kesubo Swamp to the north and the Siracho Escarpment to the east, both within the National Reserve. The reserve is also famous for its geysers and hot springs.

The lake waters are of Na-HCO3-CO3 composition. They originate from inflow from the Sandai and Emsos rivers, and from about 200 alkaline hot springs that are present at three onshore sites: Loburu, Chemurkeu, and a southern group (Ng'wasis, Koibobei and Losaramat). Other springs discharge directly from the lake floor. Lake Bogoria also contains the highest concentration of true geysers in Africa (at least 18 are known). The lake waters are saline-alkaline. The lake has no surface outlet so the water becomes saline mainly through evaporation, which is high in this semi-arid region. The lake itself is stratified with less dense surface waters lying on a denser more saline bottom waters. Although hyper-saline, the lake is highly productive with abundant cyano-bacteria that feed the flamingos. However, few other organisms inhabit the lake.

The lake has not always been saline. Sediment cores from the lake floor have shown that freshwater conditions existed for several periods during the past 10,000 years, and that lake level was up to about 9 m higher than its present level of about 990 m above sea-level. At times it might have overflowed northward towards Lake Baringo. At times, during the late Pleistocene it might have been united with a larger precursor of modern Lake Baringo, but this is still uncertain.

Chege David Mathea Reg No: WLC0811142317 Page 15

13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009

The lake area was the traditional home of the Endorois people, who were forced to leave the area in the 1970s and are now challenging their removal at the African Commission on Human and Peoples' Rights.

LAKE ELMENTEITA

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. The major Nairobi—Nakuru highway runs along the nearby escarpment affording motorists a spectacular vista towards the lake. At the southern end of the lake lie the "Kekopey" hot springs, in which the Tilapia Grahami breeds. Very popular for bathing, the local Maasai claim that it can cure AIDS. The reed beds nearby are fishing grounds for Night Herons and Pelicans

The Lake Elmenteita area saw its first white settlement when Lord Delamere (1879- 1931) established his Soysambu, a 48,000-acre (190 km2) ranch, on the western side of the lake. Delamere gave the land nearest the lake to his brother-in-law, the Honourable Galbraith Lowry Egerton Cole (1881-1929), part of whose "Kekopey Ranch", where he is buried, is preserved today as the Lake Elmenteita Lodge.

The nearby Soysambu estate is still occupied by Lord Delamere's descendants, including the controversial Thomas P. G. Cholmondeley who has been instrumental in setting up the Soysambu conservancy. The conservancy covers 2/3 of the shoreline and is home to over 12,000 wild animals. The lake's shores are grazed by zebra, gazelle, eland and families of warthog. Lake Elmenteita has been a Ramsar site since 2005. Nearby is the Kariandusi Museum, an important prehistoric site where stone hand-axes and cleavers were discovered in 1928 by Dr. Louis Leakey.

At the Lake Nakuru/Elmenteita basin, over 400 bird species have been recorded. Elmenteita attracts visiting flamingos, both the Greater and Lesser varieties, which feed on the lake's crustacean and insect larvae and on its suspended blue-green algae, respectively.

Chege David Mathea Reg No: WLC0811142317 Page 16

13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009

Tilapia fish were introduced to the lake from Lake Magadi in 1962 and since that time the flamingo population has dwindled considerably. The tilapia attract many fish-eating birds that also feed upon the flamingo eggs and chicks. Over a million flamingos that formerly bred at Elmenteita are now said to have sought refuge at Lake Natron in Tanzania.

The lake is normally very shallow (less than 1 m deep) and bordered by trona- encrusted mudflats during the dry seasons. During the late Pleistocene and early Holocene, Lake Elmenteita was at times expanded and united with Lake Nakuru, forming a much larger dilute lake. Remnants of the former joined lake are preserved as sediments at various locations around the lake basins, including former shorelines.

LAKE KAMNAROK

Lake Kamnarok is situated at the base of the Kerio Valley. The name originated from the word narok, which is a species of water plant that was widely found in the lake in the early stages of the lake formation. The lake is 1 km² in size. It was formed in year 1961 as a result of the Kerio River changing its course, therefore forming an oxbow lake. The dramatic event of its formation saw people living in the area being evacuated in order to save lives.

The lake was gazetted in 1984, and it saw the creation of the Lake Kamnarok Game Reserve, which is the home of 500 elephants. Like other Great Rift Valley lakes, its existence is being threatened, mainly because of farming activities in the area. There are deep gullies that are likely lead to spilling of the water, thus joining it with the Kerio River. A few measures have been taken to save the lake, including building of gabions. The tributaries that empty their water to Lake Kamnarok include the rivers Ketipborok, Cheplogoi, Oiwo, Lelabei and Torok.

LAKE LOGIPI

Lake Logipi is a saline-alkaline lake that lies at the northern end of the arid Suguta Valley in the northern Rift. It is separated from Lake Turkana by the Barrier volcanic complex, a group of young volcanoes that last erupted during the late 19th Century or early 20th Century. Chege David Mathea Reg No: WLC0811142317 Page 17

13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009

Saline hot springs discharge on the northern shoreline of Lake Logipi and at Cathedral Rocks near its southern limit, and help to maintain water at times of extreme aridity. During the rainy season, the lake is also recharged from the Suguta River which flows northward along the Suguta Valley, periodically forming a temporary lake, Lake Alablab, which unites with Logipi.

Lake Logipi has a maximum depth of 3 to 5 m, and is about 6 km wide by 3 km long. Its waters are of sodium bicarbonate composition. Efflorescent salt-crusts (trona) are present around its margins. Flamingos frequently inhabit the saline waters feeding on cyano-bacteria and other plankton.

Chege David Mathea Reg No: WLC0811142317 Page 18

13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009

IMPACT OF HUMAN ACTIVITY ON OUR LAKES

The three countries bordering Lake Victoria—Uganda, Kenya and Tanzania —have agreed in principle 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. However, this tax has not been put into force, enforcement of fisheries and environmental laws generally are lax, and the Nile perch fishery remains in essence a mining operation.

Currently, the Nile perch is being over-fished. Populations of a few endemic cichlid species have increased again, particularly one to three species of zooplankton-eating, herring-like cichlids that school with the abundant native Silver Cyprinid, known locally as dagaa (Tanzania), omena (Kenya) or mukene (Uganda). In 1996 The World Bank funded a project to restore and sustain the ecology of Lake Victoria and its fisheries, called LVEMP (Lake Victoria Environmental Management Project).

Meanwhile, the European Union invested another large sum in fisheries infrastructure and monitoring. One product of these foreign aid programmes has been the training of a new generation of East African aquatic ecologists, conservation professionals, and fisheries scientists. There has also been an increase in the fishery research institutes of the lake. The only outflow for Lake Victoria is at Jinja, Uganda, where it forms the Victoria Nile. The water originally drained over a natural rock weir. In 1952, British colonial engineers blasted out the weir and reservoir. A standard for mimicking the old rate of outflow called the "agreed curve" was established, setting the maximum flow rate at 300 to 1,700 cubic meters per second depending on the lake's water level.

In 2002, Uganda completed a second hydroelectric complex in the area, with World Bank assistance. By 2006 the water levels in Lake Victoria had reached an 80-year low, and Daniel Kull, an independent hydrologist living in Nairobi, Kenya, calculated that Uganda was releasing about twice as much water as is allowed under the agreement and was the primary culprit in recent drops in the lake's level. At 55,372 cubic meters per second, more than double the maximum agreed curve, it would take a year to drain 110.75 cubic kilometres from the lake. That is approximately 4% of the lake's volume.

Chege David Mathea Reg No: WLC0811142317 Page 19

13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009

Since the 1900s Lake Victoria ferries have been an important means of transport between Uganda, Tanzania and Kenya. The main ports on the lake are Kisumu, Mwanza, Bukoba, Entebbe, Port Bell and Jinja. The steamer MV Bukoba sank in the lake on October 3rd, 1995 with a loss of nearly 1,000 lives in one of Africa's worst maritime disasters.

The water lily (water hyacinth), a native of the tropical Americas, was introduced by Belgian colonists to Rwanda to beautify their holdings. It then advanced by natural means to Lake Victoria where it was first sighted in 1988. There, without any natural enemies, it has become an ecological plague, suffocating the lake, diminishing the fish reservoir, and hurting the local economies. By forming thick mats of vegetation it causes difficulties to transportation, fishing, hydroelectric power generation and drinking water supply. By 1995, 90% of the Ugandan coastline was covered by the plant. With mechanical and chemical control of the problem seeming unlikely, the mottled water hyacinth weevil (Neochetina eichhorniae) was bred and released with good results. On the Kenyan site, however, neglect has led to significant economic impact making it difficult to reach the harbour of Kisumu, hurting fishing, and threatening the 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. Between the town and the lake is a vast city dump where everything from junked automobiles to garbage rots, slowly feeding a modern array of synthetic chemicals into the soil where rainwater flushes it into the lake. When garbage is burning, a pall of acrid smoke hangs over the area. On other days, countless toxic chemicals leech unseen into the ground, eventually to reach the lake. To the east, south and west of the lake is agricultural land where DDT, Dieldrin and a host of other pesticides are widely used. These too find their way into the lake and, according to scientists, may soon reach levels that could wipe out much of the bird life.

Chege David Mathea Reg No: WLC0811142317 Page 20

13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009

At the current rates of input, the concentration of pesticides in the lake is likely to increase tenfold in 15 years. The Environmental Pollution Research Unit of the Kenya National Parks estimates, however, that before then the fish and flamingos would be dead. Already a few pelicans are dying from what is believed to be the combined effects of several toxic chemicals each of which exists in sub-lethal levels.

One of the world's most beautiful natural habitats is taking the brunt of the water pollution, pesticide pollution and solid waste pollution of a town growing at an annual rate of 6.8 percent and an agricultural region that must feed the increasing millions of Kenyans who live in arid parts of the country. Yet Lake Nakuru is also the scene for one of Kenya's first and most ambitious environmental monitoring programs. It is an effort that could become the prototype for an ecological early warning system to be used throughout Africa.

Prevention of this result appears difficult at best. To suggest that Kenyan farmers sacrifice productivity by cutting back on fertilizer and pesticides would only shift the suffering from birds to people. However, much could probably be achieved by agricultural extension programs to teach more efficient use of fertilizers which are often applied at the wrong times and in the wrong ways. More crucial however, is the use of pesticides. Although some of this could be cut down by similar more efficient methods, the main problem is more basic.

When the U.S. and other industrialized countries banned the use of DDT, many manufacturers stepped up efforts to sell off huge stocks in the "underdeveloped" world. DDT was already attractive to African farmers because of its low cost and high effectiveness. In a continent beset with famine, it is not easy to argue that food production should be sacrificed now to protect the health of generations yet unborn.

In the same way, it is difficult to suggest that with unemployment rates of 20 to 30 percent in the cities, the pace of industrialization should be slowed by the insistence on expensive pollution controls.

Chege David Mathea Reg No: WLC0811142317 Page 21

13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009

Few people here argue that stiff pollution controls should be imposed now. Rather they suggest a compromise that involves monitoring the pollution (the Nakuru research is the prototype) until it reaches the danger level and then doing something about it.

Idealistic Americans often say to Kenyans, "You got a beautiful country. You should start now to protect it. You should learn from our grave mistakes in the United States." Kenyans almost invariably reply something to the effect of, "Lets trade places. Give us your standard of living and we'll take your pollution too."

Chege David Mathea Reg No: WLC0811142317 Page 22

13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009

CONCLUSION

THE WAY FORWARD TOWARDS THE FUTURE

Kenyans have resolved to embark on the following measures to ensure conservation of our lakes for sustainable utilization in the future;

(a) Protection of the habitat of globally significant biodiversity because of improved land and water management;

(b) Increased awareness and understanding of conservation of biodiversity through sustainable natural resource management;

(c) Development of replicable models for community-based conservation of biodiversity of global importance.

(d) Improved collaboration between local authorities, communities, and NGOs on biodiversity conservation;

(e) Empowered local communities capable of addressing land and water management issues in an integrated manner;

(f) Protection of endangered habitats for grazing herbivores and migratory birds;

(g) Improved technical capacity of local authorities to support community based enterprises;

(h) Improved capacity (technical and financial) of NGOs and community groups to ensure long-term conservation of the lakes area; and

(i) Dissemination of lessons learned to other projects, including the "Conservation and Sustainable Use of Biodiversity in the Eastern Rift Valley Lakes which is currently under preparation with GEF

Chege David Mathea Reg No: WLC0811142317 Page 23

13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009

The baseline actions focus on achieving sustainable land management in the following ways:

(a) Demonstration projects on high-yielding pasture and fodder production;

(b) Afforestation and re-afforestation

(c) Establishment of a nature reserve;

(d) Awareness environmental education for local communities; and

(e) Alternative livelihood for local people, especially women.

These efforts are likely to succeed because of:

(a) High political commitment;

(b) Major local government and community involvement in project development and implementation; and

(c) Establishment of conservation-based enterprise as an incentive to raise awareness among the intended beneficiaries about the ecological and financial benefits associated with improved conservation of natural resources.

The alternative actions are:

(a) Promotion and adoption of integrated approaches to land and water management;

(b) Wildlife conservation activities;

(c) Provision of environmentally sensitive economic activities for the local people as a means to reduce pressure on biodiversity/natural resources.

Chege David Mathea Reg No: WLC0811142317 Page 24

13TH WORLD LAKE CONFERENCE, OUR LAKES, OUR FUTURE November 1, 2009

REFERENCE

Blackwell, Basil. (1987) UNEP Environment Data Report 2nd Edition U.K.

Encarta, Encyclopedia. (1988) Encyclopedia Encarta Inc. USA.

Korir Koech (Dr).. (1988) Environmental Education Kenyatta University, UON Printing Press, Nairobi.

Swan, J.A et al. Environmental Education Strategies towards a more reliable future.

Chege David Mathea Reg No: WLC0811142317 Page 25