The Dead Zone, known scientifically as a hypoxic area that is unable to sustain life, occurs every summer due primarily to excess nutrient pollution from human activities throughout the Mississippi River watershed.
One of the biggest offenders is fertilizer that runs off farmers’ fields into the Mississippi and Atchafalaya Rivers, which carry the nutrients to the Gulf, where they stimulate an overgrowth of algae that can stretch as far as the Texas border.
The Environmental Protection Agency (EPA) is restricted in its ability to control nutrient pollution because Congress exempted agriculture from the Clean Water Act of 1972. Since the 1950s, levels of nitrogen – a key component of fertilizer – in the Mississippi River watershed have tripled.