Water Quality of the Gulf of Mexico

Water quality is determined by the interaction of physiographic setting with human activities and is measured as the degree of eutrophication—the clarity of water—and the levels of contaminants. The patterns and trends in the Gulf of Mexico water quality are highly variable in space and through time. Assessments conclude that water quality in the Gulf of Mexico coastal environments is highly influenced by human activities, and the primary cause of degraded water quality is excess nutrients. The resulting eutrophication has led to low dissolved oxygen and increased chlorophyll a concentrations, diminished water clarity, and other secondary effects including toxic/nuisance algal blooms and loss of submerged aquatic vegetation. Overall, the ecological condition of the coastal northern Gulf of Mexico was judged as fair to poor, water quality was fair, and expressions of eutrophication were high.