Dear Philippe!

I think it doesn’t matter what we call it a plant or a farm as soon as this is symbiosis of both. Trees growing on effluent in Egypt is great. What are the trees later used for?
I really like dry toilets with or without urine diversion but from my practical experience think their use is quite limited (unfortunately) People want flush toilets in their homes – that’s reality and very few would bother with installing UDT, change toilet behavior, put extra piping for separate flows, etc. Too much work, trouble and money. A mixed flow pipe coming out of house – that’s probably all what we have to deal with . I think it is more realistic to try to recover nutrients from that pipe. I see it like small-scale solid free sewer serving small neighborhood community and connected to the commercial polyculture small scale plant/farm growing organic stuff and animals and employing people from that community. Something like little Soviet collective farm))). The technology is probably septic tank at each yard or cluster and solid free sewer to the farm. Desludging and other maintenance is provided by the farm machinery which takes the sludge to the farm for composting or biodigesting with animal manure and agriculture wastes. Solid free effluent goes to the farm where treated through trickling filters (possibly vermifilters) with replaceable filter substrate that used later as growing media. Treated effluent goes to constructed wetland and then possibly crop irrigation in growing season or discharge.
I am not sure if this system would work for a city unless the farm is located on a brink of it. Or it should be a different city. But at least the above scheme can be a model for rural development plan.
Is that realistic?
Regards,
Bogdan

Dear Bodgan,

In my view, it really depends on the water and nutrient availability and costs, and the capacity of the sanitation system endproducts to actually meet the (large) demand of farms. I would rather see a wastewater treatment company/utility owning agricultural land rather than farmers owning and running a wastewater treatment plant. In Upper Egypt for example, the utility owns a few tree farms directly attached to large-scale WWTPs.

What do you have exactly in mind in your case? Small-scale sewer-based systems or a network of urine-diverting dry toilets such as done by Sanergy?

Cheers,

Philippe

Dear Philippe!

Thank you very much for the response and for the very useful links to information! I will work through them the next days.
You mentioned very interesting subject - scaling up and centralizing the maintenance service for the decentralized units as a strategy. This introduces the necessary quality control.
It seems to me like real decentralized closed loop ecosanitation can exist ONLY when attached to active commercial agriculture production where the direct financial benefits on saving on fertilizers are observed and waste flows are turned into money. Basically we talk not about WWT plants but WWT farms. Can we expect that farm to provide maintenance for the “subscribers” collecting systems and include the costs into their product?

Perhaps the way forward is not sanitation but value. If it can be shown that the resource has a value with sanitation a secondary benefit both aspects succeed. It's ironic that such an idea would turn a decentralised system into a centralised system to achieve good sanitation and environmental outcomes.

Dear Bogdan,

Happy New Year!

That's a very interesting discussion topic, and I think both perspectives are right: there is a big potential for decentralised WWT in Ukraine, but it is also clear that one cannot expect every village or community to run its own WWTP properly. This is the biggest issue with small-scale/decentralised sanitation, and Ukraine would not be the only country in that case.

I've been working for five years on this topic in Egypt. There as well: a lot of potential, but many barriers. What we found, and was also concluded by other practitioners and researchers in other contexts, is if the wastewater treatment is decentralised, it still needs a certain level of centralised management. This means that you need to think at scale from the start, to be able to achieve economies of scale both in terms of implementation, and in terms of management. If you implement decentralised WWTPs in 50 villages, then you may have a small company in charge of monitoring, major O&M, and advice to local operators. This centralised management can be done either by the government, or by a private service provider. As mentioned by Kathy Eales for the case of Indonesia , "Scaling up entails more than replicating a large number of discrete projects".

You may be interested to have a look at our final report for the case of Egypt, on www.sandec.ch/esriss : Policy Recommendations for the Scaling-Up of Small scale Sanitation in Egypt .

I would also recommend the following report from WHO which provides case studies from Eastern Europe and Central Asia: Taking policy action to improve small scale water supply and sanitation systems. Tools and good practices from the pan-European Region .

All the best,

Philippe Reymond

Hello Everyone and Happy New Year!

I would like to initiate a discussion in Ukrainian media about the opportunities for decentralized WWT instead\together with traditional centralized one in Ukraine. Of course I am totally for decentralized sanitation. However, -- I would like to have more balanced views collected before stepping out as I am directly involved with promoting decentralized sanitation and therefore an interested person.
Ukraine is an empty field for sanitation at the moment. Only 3 percent of rural population has access to centralized WWT with the rest relying on whatever -- outhouses, leaking septic tank, straight pipes to the streams and so on. On the other hands WWTP serving towns are mostly in a very bad state since they were often built during Soviet times and worn out, undersized or technically outdated. Pollution of ground and surface water is catastrophic. And this in the middle of Europe (at least geographically)))!
My position that this is actually a very good situation since instead of copying and adopting expensive, energy consuming, non-recycling , cross-subsidised centralized WWT system of developed world we can leapfrog towards decentralized systems with source separation, local community based, nutrients and water recycling, integrated water management and so on. All the good stuff we are dreaming about and which inspires you and me.
However in my personal discussions I too often hear that this is a way too idealistic view. What I hear is that majority of people are too undereducated, reckless and passive to take proper care about their sanitation needs. Centralized plants are the only way to solve the problem. Either someone will come and build WWTP and connect people to them or there will be same no proper sanitation and same pollution.
But who will pay for that? EU funds like the case of Eastern EU countries? Ukraine is not EU country and probably never will be in foreseeable future. Why do no we rely on our own resources, common sense and latest ecosaniation knowledge? Why not to make Ukraine an example of eco innovations instead example of backwardness ? Back to the argument above.... People are not ready… Idealism… A vicious circle
Maybe a more spotted picture is needed. Maybe somewhere where communities are strong and willing ecosanitation is possible while major agglomerations need centralized end of the pipe plants.
Anyway I will be glad if some discussion happens. Ukraine is interesting place where we can learn a lot! Chaos bears opportunities for creative order!