New publication by Edward Jones: Global estimates of wastewater collection, treatment and reuse

About 50% of the waste water is treated. Sigificantly more than estimated previously, but developing countries lag behind. See the paper and data set in Earth System Science Data and the news release. 

Gridded wastewater production (a), collection (b), treatment (c) and reuse (d) ( MCM per year) at 5 arcmin spatial resolution.

Gridded untreated wastewater flows (MCM per year) at 5 arcmin spatial resolution.