Major environmental problems in Uganda include overgrazing, deforestation, and primitive agricultural methods, all of which lead to soil erosion. Attempts at controlling the propagation of tsetse flies have involved the use of hazardous chemicals. The nation's water supply is threatened by toxic industrial pollutants; mercury from mining activity is also found in the water supply. Uganda has 39 cu km of renewable water resources with 60% used for farming and 8% used for industrial activity. Roughly 80% of the nation's city dwellers and 47% of the people living in rural areas have access to pure drinking water. Forests and woodlands were reduced by two-thirds between 1962 and 1977. By 1985, 193 square miles of forests were eliminated. Between 1983 and 1993, an additional 7.7% of forest and woodland were lost. Wetlands have been drained for agricultural use. Poaching of protected animals is widespread. Uganda's three national parks total over 6,300 sq km (2,400 sq mi). As of 2001, 7.9% of Uganda's total land area was protected. The same year, 18 of the nation's mammal species and 10 of the nation's bird species were endangered, as well as 8 species of plants. Endangered or extinct species include the mountain gorilla, northern white rhinoceros, black rhinoceros, and Nile crocodile.
In 1996, water hyacinth growth created a serious environmental and economic problem on Lake Victoria. By some estimates, the hyacinths covered 6,000 ha (14,820 acres) of water, still less than 0.1% of the lake. When the masses of hyacinths drift into Uganda's ports and coves, they impair the local fishing, trap small boats in ports, and keep fish under the plants. The weed invasion has also been known to affect cargo boat and ferry transportation by fouling engines and propellers and making docking difficult.