5 Minute Diet

As my brother jokes when he returns from the loo, he just did the five minute diet. It’s a place that can be joked about because, for most of us, the experience takes place in a pleasant little room with a Glade air freshener, some magazines, and an effective swoosh of water at the end to make it all go away. As I’ve written recently, Haitians don’t enjoy such luxury. I believe that everyone deserves a nice place to shit, and fortunately, so does UNICEF.

We are applying for a UNICEF grant which will fund the construction of sanitation systems at twenty schools. This system will be more than just a seat and a pit. We are talking about a sustainable composting system that won’t require costly pumping, won’t contaminate the precious groundwater, and won’t stink up the air. Also, a place to properly wash hands, and a bio-sand filter to produce drinking water from the undrinkable stuff pumped out of the ground. Where necessary, we will rehabilitate or install a new well and pump accessed by the school as many of these are far away or were damaged in the earthquake. And of essential importance, education programs- designed and led by the local All-Hands volunteers- will precede and follow the construction of the system with the goal of extending the hygiene practices from the students on to their homes and families. Of the 33 schools which were assessed for this project, the twenty that were chosen are in the most dire need, and indicated a strong interest and commitment to forming this partnership with us. These twenty systems will serve 4555 students and 167 teachers.

I was tasked with developing a new design for the toilets and hand washing stations that could be efficiently built and easily adapted to the various sizes of schools. Of utmost importance is the use of materials that are readily available in-country and building methods that are transferrable to the local builders- after all, All-Hands will only be here for so long and there will still be millions of Haitians who would benefit from such a system. There are many details yet to be worked out including specifying the rebar and completing an analysis of the structural integrity in a seismic event. I will have the help of a few experienced engineers who are volunteering here. I would greatly appreciate any comments or suggestions that any of you may have about the conceptual design presented below.

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  1. One thing i wondering is if the heat and humidity will increase the rate of composting? So therefore you could lower the rate at which composting is needed.

    The designs look great!

    Also what happening with the composted waste? Is it safe for putting on food fields, or just livestock fields? It sounds like an interesting time to be down there. You will make your mark for sure. Maybe instead of being called a Crapper, it can be called a Doyle. 😛

  2. Hi Luke. Thanks for your feedback.

    The nine month composting period is expected based on our group’s experience thus far in Haiti. You are correct, heat will increase the rate of composting but only up to a certain point after which the heat can kill off the microbes which are doing the composting work. This is one reason why we don’t have the vault buried in the cooler ground, and why we will paint the outside of the vault black if the temperature proves to not be enough. Humidity needs to be minimized to facilitate the composting process which is why the design includes black-painted vent pipes (black to induce convective air flow) with a false floor to allow air flow under the pile of waste.

    The composted waste is suitable for all agriculture provided that the composting process has had enough time to complete and in the appropriate presence of heat, humidity and organic material. This is simple to accomplish but it requires that the overseers of the composting toilet have an understanding of the proper use and maintenance. That being said, it is illegal in the US to use compost derived from human waste for agriculture (not sure about Canada). This is unfortunate because it draws from one of the economical advantages of composting toilets, and results in more environmentally harmful flush toilets (water abusers) and treatment plants (hazardous chemicals and enzymes added to facilitate the process).

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