Although it has rich water resources, North Korea has had difficulties maintaining its water supply, and its rivers and streams have become severely polluted, the U.N. Environment Programme (UNEP) said in the first such study of the reclusive country, published Friday. UNEP said Pyongyang provided assistance from 20 public and academic agencies in the country for the study, which was launched at UNEP headquarters in Nairobi with North Korean officials attending. The study said 80 per cent of surface water have been utilized for hydropower generation while rivers and streams have become polluted, including the Taedong River, which flows through Pyongyang. It said dozens of factories and plants have been discharging 30,000 cubic metres of wastewater into the Taedong everyday. The Amnok River, on the boundary between China and North Korea, is also severely affected by industrial and domestic sewage, the report found. In addition, UNEP said North Korea's forests have undergone serious decline in past decades because of timber production, high levels of firewood consumption, wildfires and drought. It said conversion of hilly land into agricultural space has also taken a toll on forests. --More 2235 Local Time 1935 GMT