Mass Fish Kill Occurs in the Potomac River in the United States

Due to a prolonged extreme heat wave, water temperatures in the Potomac River reached record highs, causing a rapid decline in dissolved oxygen levels and triggering a widespread fish kill in the river’s Maryland section. In addition to rising temperatures and oxygen depletion, urban stormwater runoff continues to carry fertilizer residues and domestic sewage into the river, with the high-temperature environment further exacerbating water eutrophication. Heat stress and anthropogenic water pollution have created a synergistic threat, continuously impacting the river’s entire biological community and placing long-term pressure on the ecology of freshwater basins in eastern North America.