Scientists estimate this year's Chesapeake Bay low-oxygen "dead zone" will be roughly the volume of 2.3 million Olympic-size swimming pools — or about average for the summertime months.
The National Oceanic and Atmospheric Administration expects 1.58 cubic miles of the bay to become hypoxic, meaning it contains low levels of oxygen. That level is close to the long-term average since 1950.
"The low oxygen levels are insufficient to support most marine life and habitats in near-bottom waters and threaten the Bay's production of crabs, oysters and other fisheries," NOAA said.
The oxygen levels are influenced by low river flow, nutrient loading...