Hello Florian,
I just want to point out three aspects relating to urine management in winter.
1. Here in Eastern Canada we have cold winter (-30 C for one week in January) and the wastewater pipes regulations force to burry the pipe under 2 meters.
2. We also have few constructed wetlands (CW) that treat wastewater from small and rural cities. They work all year long because wastewater flow enters at about 50 cm under the ground level and this is about the level all along the the CW.
3. To prevent urine pipe freezing, I think, like Chris, that mixing with the high volume and sometime hot (shower) of grey water would be an option.
Cheers,
Charles, student in ecological sanitation

Dear Florian,

Good question. I remember someone from Europe (maybe in the Ecosanres yahoogroup) saying they had tried perforated hoses and that they categorically did not work. (I do not believe there is any mention of perforated hoses in the 1998 or 2004 versions of the Ecological Sanitation book.) Before that, I was already doing it here in the Amazon and knew that it worked, at least in a warm, humid, biodiverse place.

I suspect that some organism eats the struvite here before it builds up enough to plug the holes. Sometimes I see an innocuous little black ant running along the hoses, but it may be a matter of microbes.

I have also learned to not use any connectors or Tees that insert into the hose, as these do get terribly plugged. Each hose has to have a fairly straight run to its perforations.

As I mentioned, I think it is key to have a plastic mesh in the urine funnel to keep sawdust and other cover materials out of the urine hoses a much as possible. I make the funnels from plastic bottles and can easily sew the mesh into place. Without the mesh, one would never know how much sawdust are throwing into the urine diverter.

This is a great thing to work out, since the urine disappears on its own, by gravity and fertilizes the plants we want fertilized, before fermenting and producing odors.

How deep does it freeze? Even if this only works with fruit trees, it would still be spectacular. It would be great to work out an effective, low-maintenance system that works all year. But you could also have the perforated hoses working in the warm months and some other system (as Kent Madin is developing in Mongolia) for freezing months.

Best wishes,
Chris

Hi Chris,

thanks for your reply and the interesting paper on your experiences...

One question to the following comment:

canaday wrote: Since Moldova is in Europe, the general consensus would be that you cannot do this, since the urine sludge(mostly stuvite) would reportadly plug the holes.

As you say "reportedly" are you aware of any similar attemps in Europe?

Aside from the risk of clogging, one problem in Moldova certainly will be freezing in winter. I see 2 options to solve this:
- Distribution pipes below level of freezing; however this would only allow to reach roots of trees, probably too deep for any other plants.
- Installing a holding tank in winter to store the urine during winter and use it in summer; the whole system tend to be complex then...

After all, I am not sure if the idea really makes sense.

Happy for more experiences and comments!

Cheers, Florian

Hi Florian, (I tried to post this on Ecosanres, but for some reason it did not work.)

I have been distributing urine via perforated hoses for 12 years. You can read about this in my paper on Simple UDDTs in Sustainable Sanitation Practice
www.ecosan.at/ssp/issue-06-toilets/issue-06-toilets

Hoses can be under 10-15 cm of sawdust or sand for better aesthetics, less damage to the hose by UV light, less evaporation of nitrogen, less incidental damage from people clearing weeds, control of potential fecal contamination. At least in the rainforest, this also reduced the chances of mammals chewing holes in the hose to get at the nutrient-rich urine.

Benjamin Clouet's "Easy Shower" combines a shower into a UDDT, with drip irrigation hoses to distribute the urine + shower water


If Moldova is the least bit dry, it would be important to combine greywater with the urine, as Benjamin does.

Since Moldova is in Europe, the general consensus would be that you cannot do this, since the urine sludge(mostly stuvite) would reportadly plug the holes. I think the lack of meshes in most UDDTs also allows some amount of sawdust and other cover materials and would contribute to plugging, in combination with struvite.

Good luck with everything and please let us know how things go.

Best wishes,
Chris

Hi all,

In our project in Moldova (rural water supply and saniation) a couple of school toilets based on UDDT have been built, with urine being collected in holding tanks for reuse on fields, feces being collected in double vaults and hand-washing water being infiltrated in soak pits.
We would like to test another way for urine reuse in the next facility to be built. The basic idea is to add the urine to the hand-washing water and to infiltrate it (via sub-surface pipes) near trees, greenery and in the school school garden.
My question is now if someone is aware of similar projects, where school sanitation facilities with urine diversion and following urine infiltration resp. subsurface irrigation and fertilisation have been implemented.

Thanks for your help,
Florian

PS: i posted the same here: tech.groups.yahoo.com/group/ecosanres/message/6983