SFI fiber sourcing certification associated with suspended sediment load reductions in Georgia, USA

The Sustainable Forestry Initiative Fiber Sourcing Standard (SFI-FSS) is a market-based certification that promotes responsible forestry by requiring certified mills to procure wood only from trained loggers and suppliers who are implementing Best Management Practices (BMPs) across the supply chain. None of the previous studies have analyzed the association of the degree of SFI-FSS adoption with improved water quality. This study examines the impact of increased coverage of SFI-FSS certified mill sourcing areas (wood baskets) on suspended sediment concentration (SSC, mg/L) and sediment load (kg/ha/yr) in watersheds across Georgia, USA. Using a spatially explicit methodology, we analyzed data from 28 United States Geological Survey (USGS) monitoring stations, incorporating information on mill certification status, land cover (forest/crop), and hydrological discharge (cubic feet per second, cfs) over a 19-year period (2001–2019). A multiple linear regression model with area and time-fixed effects was used to assess the relationship between SFI-FSS mill presence and sediment load in watersheds overlapping the mill wood baskets. A 1% increase in SFI-FSS certified mill sourcing area within a watershed is associated with a 3.5 kg/ha/yr reduction in median suspended sediment load (p < 0.01). This relationship indicates that increasing SFI-FSS certification coverage correlates with improved water quality by reducing sedimentation. Forest cover (%) also exhibited a significant inverse relationship with sediment load, reinforcing the well-documented role of forests in water filtration and sediment retention. These findings provide empirical support for the role of SFI-FSS certification programs in promoting water quality benefits. As certification programs continue to expand, their potential to contribute to sustainable watershed management should be further explored.