Great Barrier Reef Outlook Report 2009: Catchment runoff information sheet

Abstract

The Great Barrier Reef receives the runoff from 38 major catchments which drain 424 000 km2 of coastal Queensland. Over the past 150 years sediment inflow onto the Great Barrier Reef has increased four to five times, and five to 10 fold for some catchments. Inorganic nitrogen and phosphorous continue to enter the Great Barrier Reef at enhanced levels, two to five times for nitrogen and four to 10 times for phosphorous relative to pre- European settlement and pesticides are now being detected in inshore waters.