Christchurch residents throw away too much paper into the landfill. Paper waste represents 21% of the total waste stream. Burying paper and cardboard results in the release of carbon dioxide and methane into the atmosphere with contributes to Climate Change. Carbon emissions from the breakdown of paper, cardboard and organic matter in the landfill amounts to the emissions generated from 33,000 cars each year.
This answer is from Christchurch City Council – Waste statistics.