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Biosolids store carbon in the soil, help plants take more carbon dioxide out of the air, and reduce the need for chemical fertilizers, which takes a lot of energy to produce.

Centuries of agriculture and deforestation have taken carbon reserves out of our soil, leading to increased greenhouse gas emissions. This carbon loss damages soil health and contributes to climate change. The good news is that it can be reversed by adding carbon back to the soil. Biosolids, which are naturally carbon-rich, are an effective way to add carbon back to the soil to fight climate change.

Using biosolids offsets almost all of the carbon emissions associated with cleaning wastewater, and it’s one of the main reasons King County Department of Natural Resources and Parks has achieved its “Beyond Carbon Neutral” commitment—ahead of schedule.

reducing our climate impact graphic

Doing our part to fight climate change with King County's Loop biosolids

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