A new paper by Tariq Aziz and Philippe Van Cappellen uses economic valuation to highlight the importance of Southern Ontario’s wetlands for sediment and phosphorus filtration. A total annual value of $4.2 billion in sediment and phosphorus filtration services was found based on the average rate of sediment accretion plus the associated total phosphorus concentration in each type of wetland in Southern Ontario and estimating how much the removal and disposal of the same amounts of sediment and phosphorus in stormwater management facilities in Ontario would cost. The study also calculated how much it would cost to replace wetlands' existing phosphorus filtration function with three different human-engineered solutions. Building artificially constructed wetlands would cost an average of $2.9 billion per year to replace the free phosphorus filtration service our natural wetlands currently provide. Implementing agricultural Best Management Practices to remove an equivalent phosphorus load would cost society $13 billion annually, while expanding current wastewater treatment capacity to replace wetlands’ filtration service would cost $164 billion per year. The paper was published in the journal Hydrological processes and can be accessed here: LINK#1. See also the news story on the university’s website: LINK#2.
Tuesday, January 25, 2022