This map identifies 415 eutrophic and hypoxic coastal systems worldwide. Of these, 169 are documented hypoxic areas, 233 are areas of concern and 13 are systems in recovery. The map is based on research conducted by WRI's Water Quality team and Dr. Bob Diaz at the Virginia Marine Institute.

Agriculture, growing industry, fossil fuel combustion, and population growth are together causing significant growth in areas receiving nitrogen and phosphorous endflows. Over the past 50 years, nitrogen flux has doubled and phosphorus has tripled, according to the Millennium Ecosystem Assessment. These cumulative changes are, quite literally, choking coastal waters around the world.