Valuing the subsurface pathogen treatment barrier in water recycling via aquifers for drinking supplies.

A quantitative microbial risk assessment (QMRA) was performed at four managed aquifer recharge (MAR) sites (Australia, South Africa, Belgium, Mexico) where reclaimed wastewater and stormwater is recycled via aquifers for drinking water supplies, using the same risk-based approach that is used for public water supplies. For each of the sites, the aquifer treatment barrier was assessed for its log(10) removal capacity much like for other water treatment technologies. This information was then integrated into a broader risk assessment to determine the human health burden from the four MAR sites.