Using grey water to grow ...

Using grey water to grow crops in constructed wetlands  placed  and planted sequentially may be an answer. Prairie grasses are excellent phytoremediators of heavy metals and can be used for gasification to produce energy while capturing the metals. A series of 5-6 sealed constructed wetland bays  with gravity flow following the grasses that are planted with crops matching declining nutrient needs and increasing salt tolerance (EC) may completely remediate pathogens on root surfaces, consume most of the effluent, prevent groundwater contamination, and prevent alkali soil conditions. Remaining phyto-treated water could be used for groundwater recharge. Edible portion of crops would not contact pathogen contaminated water, no aerosols would be generated, and CEC's would be remediated by energy crops. 

Water-Energy-Food--solution for one is the solution for all.