Dear Researchers for Grey water solutions.
In one of a Resort having huts at areas near Reserve Forest and water body etc.
Use of bio soaps and hot water for degreaser cleaners were resorted to. All grey waste water ex. 30bed x 150 lts say 5 kl per day remedied using Dewats wwt plant and water and sludges re used.
Toilets discharges were taken to twin-pit mechanism etc.
All wastes remedied to re use mode.
Well wishes.

Hi Tendai,
Just in case you haven't done this yet, you can also search the SuSanA library for documents on greywater treatment and reuse.

You can either filter the library by "reuse type": select "greywater or wastewater", which gives you these results:
www.susana.org/en/knowledge-hub/resource...5&vbl_2%5B%5D=&test=

Or you put greywater into the search field which gives you these results:
www.susana.org/en/knowledge-hub/resource...title=&author=&year=

Try also "grey water" in two words. For this you have to used the search option of "exact phrase". Results:
www.susana.org/en/knowledge-hub/resource...title=&author=&year=

I also tried the American spelling and got this for "gray water":
www.susana.org/en/knowledge-hub/resource...title=&author=&year=

And nothing for "graywater".

Kind regards,
Elisabeth

Thanks Tendai,

Must the system be relocatable?
"High settlement densities" in this context to me would require something modular, scaleable and relocatable, therefore not centralised. The larger the plant the more difficult to relocate. Will you want equipment that can be easily uplifted and with surface pipes? Is energy (electricity or solar panels) available?

So should the greywater be treated at source or destination? It must be transported from the dense settled areas to adjacent land that can grow crops. Is such land available and downhill from the settlements?

Is the greywater originating from shared communal facilities? If so this would keep costs down, but on average how many litres per day will be generated from a facility?

The treatment level you require is a sticky point, you say that the water will come into contact with plants that will be eaten raw. This requires the very best quality of effluent. In this case you don't need to be concerned about nitrogen (N) levels, but pathogens are of concern. Clearly the easiest way of producing crop irrigation water is to just remove the solids and grease. If you look at Kris's document "GREYWATER TREATMENT IN SAND AND GRAVEL FILTERS", there is a diagram of a bio filter (p.11) which will do that at source. The greywater can go through the biological filter and straight to irrigation, which is a nice simple system. But I doubt that the pathogen levels will be low enough to eat the vegetables raw. This is a big ask... the very best of treatment levels, requiring far more cost and effort.

Because constructed wetlands are not easily relocated, another option is to use bio filters in series. However this requires fall from the source to the destination (or available energy for pumping). It also requires tanks of some sort. What materials do you have that are available and cheap? Are used 220 l plastic drums cheap and available?
cheers
Dean

Hie Dean

My focus is to treat the water for unrestricted irrigation where there is a likely contact of treated water with plants some which may be eaten raw. The treatment system should be compatible with high settlement densities. The process is oriented more towards treatment rather than disposal.

Cheers!!

Hi Tendai,
what level of treatment do you require? Although constructed wetlands are an option they could be seen as using a sledge hammer to crack a nut... and not so reusable? Point discharge into a waterway is very different from dispersal to land. Effluent quality can be lower with a larger dispersal field. Do you put more effort into treatment or dispersal? To answer this I'd need more details.
cheers
Dean

Thanks Rochelle, much appreciated.

Thanks Kris, the documents are useful.

Maybe not exactly what you are looking for, but please find attached two documents to help designing basic low-cost grey-water treatment systems that I found useful for work in refugee settlement facilities.

Dear Tendai,
We have done some work on greywater reuse here in Malawi that you may consider:

Newcomer, E., Boyd, C., Nyirenda, L., Opong, E., Marquez, S. and Holm, R. Reducing the burden of rural water supply through greywater reuse: A case study from northern Malawi. Water Science & Technology: Water Supply, 2017, 17(4), pages 1088-1096. DOI: 10.2166/ws.2017.004 ws.iwaponline.com/content/17/4/1088

Best of luck,
Rochelle

Hie all,

I am working on a provisional onsite greywater (gw) treatment system for reuse in informal settlements in South Africa. Henceforth l am interested in publications and experiences in this regard. I would be much grateful for leads especially with gw treatment and reuse systems that have been implemented in developing nations.

Cheers!!!