The decline in river oxygen levels poses significant risks to biodiversity, water quality, and human livelihoods. Dead zones, similar to those in the Gulf of Mexico and Chesapeake Bay, could become more widespread, leading to fish die-offs and reduced biodiversity. Communities relying on fishing and agriculture may face economic and food security challenges. Warmer water temperatures will also make rivers more susceptible to pollution, further degrading water quality and increasing the risk of ecological crises.