Nitrous oxide emissions from wastewater treatment in the U.S. 1990-2022
Nitrous oxides (N₂O) emissions from wastewater treatment in the United States totaled nearly 22 million metric tons of carbon dioxide equivalent (MtCO₂e) in 2022. Domestic treatment was the largest source of emissions, with 7 MtCO₂e, while domestic discharge released 4.4 MtCO₂e. Since 1990, N₂O emissions from wastewater treatment in the U.S. have increased.