Biochar use in stormwater management
Every rainfall event carries nutrients, metals, bacteria, and emerging contaminants into water drainage systems. Most of this water is discharged into lakes and rivers, but more and more of this runoff is being filtered before it leaves a site.
Biochar’s internal pore network increases water holding capacity and helps maintain infiltration performance. That same porous structure allows biochar to adsorb nutrients and certain metals, stopping them before they flow further. Biochar is well known for its effectiveness at removing common stormwater pollutants like heavy metals, hydrocarbons, and particulates. At the same time, researchers are examining how specific biochar formulations interact with emerging contaminants such as PFAS.
In stormwater applications, biochar functions as part of a filtration system. It’s often applied in stormwater green infrastructure best management practices like bioretention, rain gardens, green roofs, and bioswales.