I just received an email from an old college friend, Parth Thaker.
Parth is an interesting guy. He had a well-paid position as a software guy in Northern Virginia, and was getting repeated promotions. However, he decided to put that on hold and join Indicorps (it's like Americorps, but for India). Now he's in Ahmedabad, India working on sanitation issues. Parth, I salute you, since what you're doing is totally awesome.
I had understood before that sanitation and the availability of clean drinking water is one of the major issues facing the developing world. In fact, Parth, Kirill, Kedar and I entered an international design competition with a half-realized sensor network designed to improve water quality through monitoring. However, India's sanitation situation is more severe than what I had understood; the problems transcend infrastructure, and touch on class distinctions.
Indeed, I had heard about the Indian Caste System, but I thought it was a thing of the past. While it has been mostly eliminated in urban centers, Parth has informed me that it is still going on in many rural locals. In some such places, it is the job of the untouchables to serve as an active sewer system, by manually removing feces. I'll let you ponder a second on how demeaning that job must be.
Even with these laborers, the overall state of sanitation is insufficient, and illness related to sewage is a major cause of child mortality. In short, infrastructure is necessary. The Environmental Sanitation Institute (ESI) and Indiacorps are trying to do something about it. The reason I think these groups are so interesting is not just their goal (many groups share this goal), but also their approach.
If you go to ESI's website, they describe their various sanitation technologies. While I usually shudder at the concept of using technology to solve all the world's problems (i.e. do cheap laptops help children in developing nations?), I think the people at ESI got it right.
ESI presents a portfolio of the designs of several toilets and related technologies. The diversity of their approach is encouraging. They have designs that fit multiple scenarios, based upon amount of water available or need for fertilizer or a fuel source, all of which assume the lack of a pressurized water source or electricity. Some don't even assume the availability of pipe. I'll review a few of those here.
(1) The Septic Tank.
This is a per-family device, and so requires more investment by the community. Additionally, it requires that the tanks remain full of water, so it can only be deployed in areas with an adequate water supply. Requires 5 liters of water per flush, and must be dredged once every five years.
It has the benefits of leaking nutrients into the surrounding area, but it does not appear that the compost can be actively harvested.
(2) The Hand Flush.
Despite its unfortunate name, this design does not require you to flush with your hands. This is a the cheapest design, and requires little space, few bricks and no pipe. The user does his business into a pan, and then dumps the pan into the hole, so it requires only 1.5 liters of water per flush. Over time, excess water, gas and nutrients seep into the soil, but solid, stable compost can be harvested from the pit.
(3) The Bio-Gas Plant.
In addition to serving as a sanitary toilet and providing compost, this design will trap the gasses (a natural byproduct of decomposition) for use as a fuel source. These gasses---mostly methane---can be used as a smokeless fuel source for cooking, as well as for powering motors or generators. How cool.
This design is much more expensive, requiring many bricks and pipes. ESI's website claims that it will return its investment in 3--4 years.
(4) The Smokeless Chulla.
This design takes the previous one step further. It is not a toilet, but rather the design of an oven which runs on bio-gas.
Although the people of these regions undoubtedly already know how to build all necessary cooking equipment, this design has a hidden benefit. Because it burns bio-gas, it is smokeless (unlike wood or who knows what else). Ultimately, this design is less hazardous to the environment and the health of the individuals who use it.
Overall, I think ESI has a lot to offer not just india, but the entire world. These designs should not be viewed as "developing nation only," since there are definately parts of the US and Europe which would benefit from them. It just goes to show that innovative minds can create amazing things, even if they lack cash or if parts are unavailable.
The efforts of ESI are incredible, and I congratulate you on finding Parth. And Parth: good luck, and keep up the good work.