marine resources. FAO data estimated that between 1990 and 1992, these foreign fleets increased their catch by 25 percent (Hinrichsen 1998).
Mangroves in Kenya are cleared for subsistence activities, some shrimp aquaculture, and salt production. The larger patches of remaining mangroves are found round the Kiunga Marine Reserve, near Lamu, from Diani to Shimoni, and near Kilifi (Hinrichsen 1998).
The coasts are also visited every year by thousands of tourists, many from wealthy European countries. These visitors, while welcomed for the revenue they bring, demand resort-quality treatment during their stay, which requires higher consumption of water, energy, and other resources, and creates greater amounts of wastes, in the already underserved coastal areas. Access to sufficient quantity and quality of water is a serious coastal constraint. Boreholes and wells in the coastal region are subject to seawater intrusion; in urbanized coastal areas an even greater intrusion issue, affecting the health of many people, is pollution from pit latrines and septic systems. Currently, there is a water supply deficit, and an increasing population, especially in and around urban areas. Many tourism centers and establishments are drilling their own boreholes, drawing down groundwater levels along the coasts; all drilling is currently unplanned and unmonitored.
Mombasa provides an illustration of the urban-coastal threats to water in Kenya. Mombasa is home to many people, all contributing sewage to the city’s sewage treatment facilities; the latter are out-of-date and able to treat only a small percentage of the waste. The city grew at an estimated 5 percent per year during the early 1990s, and is expected to roughly double its population of that period before the year 2019, leading to the inevitable conclusion that more effort needs to be made in establishing safer sanitation provisions.
5.2.3. Agricultural development and water resources
Conversion of Kenya’s wildlands for agricultural development, as noted above, is at the root of much degradation and environmental loss throughout the country. Wetlands are especially vulnerable to this trend, both because they are fragile systems and because their soils are more fertile than most dryland areas.
Hydrological schemes for irrigation and energy production are particularly problematic. In 1991, 59 large-scale dams were in place or underway in Kenya (Keter 1991). For example, the Sasumua Dam in the Aberdares provides water to Nairobi and to irrigation sites nearby; sites including Kamburu, Gitaru, Kindaruma, and Kiambere on the Tana River are dammed; and a new dam recently created the Turkwell Gorge Lake. Irrigation projects, including Mwea-Tabere, Yala, Sondu, West Kano, and Ahero, had reclaimed some 7,800 ha for growing rice and sugar by 1991 (Mavuti 1991) and have probably been significantly extended since. A power project on the Tana River at Masinga has in its few years of existence received large volumes of silt and may become a floodplain within a few decades (Nyamweru 1991).
Agriculture is generally a damaging practice, unless soil conservation measures and environmentally benign inputs are carefully applied. Sadly, this is the exception rather than the rule. Yala Swamp, covering 17 km2 in the northeast corner of Lake Victoria, has been partially reclaimed for agriculture. The Yala Swamp houses some of Kenya’s endemic bird species, including the Papyrus Yellow Warbler. In one corner of the swamp is Lake Kanyaboli, which support a rich fishery and key nursery for important subsistence fish species, producing an estimated 250 metric tons in 1981. It is a “living museum” representing what Lake Victoria’s fishery would have been like before the 1960s, yet it is threatened by increasing salinity – up 100 percent from 15 years ago, due to the diversion of the Yala River and construction of a dyke (Mavuti 1991).
Pesticide use is higher compared with other developed countries (Kallquist and Meadows 1977) and is especially a danger to wetlands with no outlets, particularly from persistent toxins (Krhoda
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