Point sources of water pollution
In the case of point sources of water pollution, in other words, when chemicals
are directly released into a surface water body in the form of a wastewater
disposal, the load can be estimated by measuring the effluent volume and the
concentration of a chemical in the effluent. More precisely: the pollutant load
can be calculated as the effluent volume (Effl, in volume/time) multiplied by
the concentration of the pollutant in the effluent (ceffl, in mass/volume) minus
the water volume of the abstraction (Abstr, in volume/time) multiplied by the
actual concentration of the intake water (cact, in mass/volume). The grey water
footprint can then be calculated as follows: