The war in Rwanda, beginning in 1990, has damaged the environment. The ability of the nation's agricultural sector to meet the demands of its large population are complicated by the overuse and infertility of the soil. Soil erosion and overgrazing are also serious. The remaining forested area is under intense pressure from uncontrolled cutting for fuel. During 1981–85, deforestation averaged 3,000 hectares (7,400 acres) per year. Between 1983 and 1993, Rwanda lost 4.8% of its forest and woodland areas. Malaria and sleeping sickness have spread because forest clearing and irrigation have increased the breeding areas for disease-carrying insects. Rwanda has 6.3 cubic kilometers of renewable water resources with 94% used for farming and 2% used for industrial activity. Only 60% of the nation's city dwellers and 40% of the rural population have safe drinking water. The nation's cities produce about 0.1 million tons of solid waste per year.
In northeastern Rwanda the beautiful Kagera National Park is a game reserve, sheltering many types of wildlife. Volcano National Park, which surrounds Mt. Karisimbi and was Africa's first wildlife park, is one of the last existing homes of the mountain gorilla, which numbered 280 in 1986, up from 250 five years earlier. The national parks suffered from uncontrolled poaching and unauthorized cultivation until recent years. As of 2001, nine of the nation's mammal species and six of its bird species are threatened with extinction. Threatened species include the chimpanzee, African elephant, and black rhinoceros. Sixteen species of fish have become extinct.