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Plastic Bottles, Compost Toilets and Rainwater Catchment: Simple Solutions for Haiti’s Clean Water Crisis

Upon hearing of the recent cholera outbreak in Haiti, it is tempting respond with despair. In spite of all the effort and aid that has been poured into that unfortunate country since last year’s earthquake, it’s hard to shake the feeling that this new crisis was at once foreseeable and inevitable—a reality that makes it all the more tragic.

Cholera is caused by a strain of bacteria that is transmitted through water contaminated by a sick person’s feces, and causes extreme vomiting and diarrhea. Untreated it can kill 50 percent of its victims.

Haitians waiting for potable water shipped in from the Dominican Republic. Source: Pan American Health Organization

There are many mysteries behind this particular outbreak—the fact that in spite of persistent poor sanitation, there has been no confirmed outbreak of Cholera in Haiti since 1960, or that according to Dr. Brigitte Vasset from Doctors Without Borders, the region most affected in the current outbreak is not the region most affected by the earthquake. Other scientists speculate that based on the strain, it is likely that the disease didn’t even originate in Haiti, but was imported; some suspect a camp of U.N. peacekeepers from Nepal.

But wherever it came from, there is no question that cholera thrives in places that lack adequate clean water and proper sanitation. Aid workers have focused most prominently on teaching Haitians to wash their hands with soap; while certainly advisable, there are many other low-cost, high-impact approaches to alleviating the clean water crises in places like Haiti, so it’s worth mentioning a few.

Composting Toilets. Most sanitation programs in Haiti focus on building latrines that must eventually be emptied somewhere. The composting toilet, however, can turn human waste into a valuable source of fertilizer, while reducing the potential vectors for disease transmission.

Most studies indicate that compost toilets are safe, especially as a replacement for pit latrines (or worse, open sewage). As a study published in the American Society for Microbiology summarized it, composting toilets that “replace the pit latrine . . . have two advantages: they do not pollute the environment and biosolid waste is sanitized. These systems have the potential to improve public health by reducing illnesses caused by fecal-oral transmission of pathogens.”

One challenge for composting in Haiti is a lack of organic material to mix with waste (high-nitrogen human waste requires a high-carbon organic material to properly compost). To address this challenge, a permaculture disaster relief group is exploring the possibility of propagating fast growing plants such as vetiver grass and bamboo. (Vetiver grass has frequently been used by permaculturalists as a means to hold back erosion on degraded slopes – another potential benefit for deforested, eroded Haiti).

Vetiver grass. Source: Permaculture Research Institute

Rainwater Harvesting. Rainwater is among the purest of water sources—at least as it falls from the sky. Finding a way to catch the water without contaminating it (on a dirty roof, for example) is another question—one highly dependent on available materials.

Unfortunately, more study needs to be done on the safety of low-tech rainwater harvesting. However, as T.H. Thomas and D.B. Martinson argue in their book Roofwater Harvesting: A Handbook for Practitioners, captured rainwater is likely to be at least as safe as any easily available alternative, at least in places where clean water is scarce. Some simple technologies, such as adding a first-flush system, can improve water quality; rain-harvested water can also be filtered.

Taking a somewhat more ambitious approach, researchers from Princeton University have designed a rainwater-harvesting unit that uses two 20-foot shipping containers and clay filters. According to the researchers, based on typical rainfall in Haiti, the unit should be able to process some 80,000 gallons of clean water each year. According to Winston Soboyejo, one of the lead researchers, replacement filters could be made locally.

Innovative design for rainwater harvesting. Source: News at Princeton.

Solar Cookers and Rocket Stoves. Okay, these don’t seem to be directly connected to water, but bear with me.

Solar cookers and efficient wood stoves can greatly reduce the burning of wood for cooking. Given the deforestation crisis in places like Haiti, anything that reduces the pressure to cut down trees is a good thing.

What may not be immediately obvious is that the deforestation of Haiti can be connected to its water crisis. Ethan Budiansky of the non-profit group Trees for the Future argues that deforestation is directly linked to the cholera epidemic. His reasoning:

“As an island country in a tropical zone, Haiti is naturally subjected to heavy rains on a regular basis. Normally, trees and other plants help absorb the water and blunt the impact of the droplets on the soil with their broad leaves. The roots of the trees, meantime, help break up the soil, making it more hospitable to smaller plants that grow nearby. When there aren’t enough trees, the soil becomes hard-packed, reducing its ability to absorb water during heavy rains. Hillsides become eroded, sending sediment into streams and lakes. Stagnant pools of water form that are havens for bacteria.”

I’m not sure I can source any journal studies to back up this chain of logic, but it makes sense. Even more directly, a case can be made that deforestation is directly tied to endemic poverty in Haiti – and thus to the conditions that lead to cholera.

Plastic Bottles. The SODIS group (short for solar water disinfection) is a Swiss organization that promotes the treatment of drinking water with plastic bottles.

The method is simple. It turns out that leaving water in a clear plastic bottle in the sun for six hours kills pathogens and makes the water safe to drink.

According to SODIS, a study by the Royal College of Surgeons in Ireland showed that the method cut cholera in Keyna by 86 percent.

The method seems particularly useful in Haiti as it allows for the reuse of the hundreds of thousands of bottles of water that have been shipped to Haiti in the wake of this catastrophe.

Finally, a good use for plastic water bottles.

The SODIS Method. Source: SODIS

There are many more simple technologies and approaches to clean water that I haven’t mentioned. The reality is that low cost, decentralized but scalable solutions to water crises like that of Haitis exist – we do not have to wait for large, capital-intensive infrastructure projects to begin making a difference, if we have the will to do so.

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Rainwater Harvesting
13 years ago

As UV light is used commercially for water sterilisation, there is no reason why the plastic bottle idea won’t work equally as well.

Sewage Treatment Plant Systems
13 years ago

It is very important that the rainwater is filtered before in goes into the bottles. UV light sterilisation only works if the water is free from small particles which the bacteria can ‘hide’ behind away from the UV light.