Flooding Creates Big Marine ‘Dead Zone’ in Gulf of Mexico

(Bloomberg) -- Fertilizer runoff amid rampant flooding in the U.S. will contribute to a nearly record-large “dead zone” for marine life in the Gulf of Mexico this summer.

The recurring hypoxin zone, caused primarily by human activities, has low levels or no oxygen, the National Oceanic and Atmospheric Administration said in an emailed report on Monday. Widespread flooding this year washed crop nutrients into rivers and subsequently into the Gulf.

The dead zone is estimated to be 7,829 square miles, roughly the size of Massachusetts and near the record 8,776 square miles set in 2017, NOAA said.

“Once the excess nutrients reach the Gulf they stimulate an overgrowth of algae, which eventually die, then sink and decompose in the water,” NOAA said in the report. “The resulting low oxygen levels near the bottom are insufficient to support most marine life and have long-term impacts to living marine resources that are unable to leave the area.”

--With assistance from Brian K. Sullivan.

To contact the reporter on this story: Michael Hirtzer in Chicago at mhirtzer@bloomberg.net

To contact the editors responsible for this story: James Attwood at jattwood3@bloomberg.net, Reg Gale, Christine Buurma

©2019 Bloomberg L.P.