I strongly believe the origin of the wastewater may not be be a factor worth to justify whether such water could/should be used for drinking purposes after treatment. water worthy for consumption should meet quality standards such as, turbidity, pollutant level, pH, alkalinity, suspended solids etc. when all water quality parameters conform to standards, then that water is good to go with.

It's only matter of the investments you can pay to treat the water. So greywater is generally better because it will (or better should) cost less to treat the water to drinking quality. But the quality standards for drinking water are still the same and there shall be no difference between black and grey water after the treatment. The only difference is only in the treatment process itself.

@Philip Antwi

Yes I agree my friend. But one source (Sewage or Grey water) is somehow better to be treated rather than treating the other. I mean cost wise and technology.

@Vit Rous

Thank for the perfect answer. Yes that is exactly what I was looking for.

If the treated water (may be treated waste or treated grey water) meets the drinking water specifications, means the water quality is within the permissible limits of drinking specifications, then it can be consumed.

I agree with the views of Dr.Philip and Dr.Vit. The only thing the suitable technology in regard to cost of treatment; this can be a parameter to differentiate the suitability of treated grey water from treated waste water.

Regards

There are a couple of water suply systems that use waste waterTREATED for municipal consumption. One of them has been operating for years en Africa

Philip Antwi Vit Rous Caner Yerli Asit Kumar Batabyal Jesús Armando Cubillos All of you described the topic in very crucial way. As per my personal opinion.The treated grey water is far better in point of view of safety. But, it recommended appropriately to use the treated grey water and waste water for non-potable purposes only. You may be interested in following articles.

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