Kampala's wetlands have been disappearing due to pollution and rapid encroachment in urban areas, and now account for only 16 percent of land cover, writes AllAfrica.com. Wetlands are vital because they serve as "sponges and water filters," and prevent flooding along lakes and rivers. The growing number of both legal and informal factories in Kampala compound the problem, as industrial waste disposal is often poorly managed. Also, human waste is often improperly treated. In comments to AllAfrica.com, Dr. Gerald Musoke, the deputy executive Director of National Environment Management (NEMA), argued that if wetland degredation isn't checked, the country may be headed for a "vast ecological disaster that may lead to persistent clean water shortages." In another article by AllAfrica.com, World Resources Institute (WRI) and the Uganda Wetlands Management Department estimate that the annual productive value of Uganda's wetlands are between sh9 trillion and sh18 trillion, and provide subsistence employment for over 2.4 million people. Wetland restoration can prevent further ecological damage, but may also be key to preserving jobs and alleviating poverty.

According to Dr. Musoke, wetlands have been converted into dumping sites for waste from factories and garages. As a result, many of these effluents end up in water bodies and infiltrate water systems whenever it rains. As industrial waste moves from the wetlands, it enters the greater Lake Victoria water system.

In addition to industrial waste, the total amount of faecal waste entering Lake Victoria is comparable to the amount received by the Bugolobi Sewage Treatment plant. AllAfrica.com adds: "It is estimated that about 5.3 tonnes of faecal waste with concentrations of 430mg/litres of chemicals pour into the Lake Victoria via city channels daily. Some of the wetlands include Nakivubo, Lusaze-Kosovo, Nsooba Nalukolongo, Kirombe and Lubigi swamp system."

Wetland areas are often illegally used to grow a variety of staple food crops. Polluted material is then absorbed into the wetlands and crops. "When they get into wetlands where crops are grown, they are extracted and absorbed by the crops." Given that urban farming is widespread, agriculture is often practiced in valley slums where poorer citizens live in informal settlements. NEMA argues that urban farmers need to stop growing crops in polluted wetland areas. Kampala's Mayor, Nasser Ntege Sebaggala, said: "I have never bought vegetables from Kampala because they are grown in areas where garages and factories are emptying untreated wastes, which are then absorbed by the crops and when you eat them, you definitely end up getting health complications."

Mayor Sebaggala added that the city is trying to evict illegal residents of wetland areas and close dirty abattoirs, but there are challenges in balancing the needs of factories, residents and local crop farmers with the demands of sustainable environmental management. In comments to AllAfrica.com, Sebaggala said: "if people were respecting the law, they would not be encroaching on wetlands as it is the case today under the pretext of practicing urban farming. We don't discourage urban farming, but let it be done in a proper manner. We have opened up a well organised area in Kyanja where such activities can take place."

Read the article and a map of existing wetlands in Sub-Saharan Africa from World Resources Institute (WRI).

Also, check out the WRI report, "Mapping a Better Future: How Spatial Analysis Can Benefit Wetlands and Reduce Poverty in Uganda."

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