Papua New Guinea's environmental concern includes pollution, global warming, and the loss of the nation's forests. Coastal waters are polluted with sewage and residue from oil spills. The nation has 801 cu km of renewable water resources, of which 49% are used to support farming and 22% for industrial activity. Only 88% of the nation's city dwellers and 32% of the rural population have pure drinking water. Another significant source of pollution is open-pit mining. The country's cities produce an average of 0.1 million tons of solid waste per year. Global warming and the resulting rise in sea level are a threat to Papua New Guinea's coastal vegetation and water supply.
The Department of Physical Planning and Environment is responsible for integrating environmental planning and conserving natural resources. In 2001, 57 of the nation's mammal species and 31 of its bird species were threatened, as were 66 types of plants. Endangered species in Papua New Guinea include four species of turtle (green sea, hawksbill, olive ridley, and leatherback) and Queen Alexandra's birdwing butterfly.