NextBillion - An Initiative of the William Davidson Institute at the University of Michigan

Wednesday, January 6, 2016

Two-and-a-half billion people worldwide have no access to safe, durable sanitation systems. Brian Arbogast, director of the water, sanitation and hygiene programme at the Bill & Melinda Gates Foundation, tellsSciDev.Net how innovative toilet technologies and business models could help fix this — and help communities cope with the devastation of climate change.

How does climate change impact sanitation?

With sea levels rising, you have flooding that causes huge health problems. As latrines and septic tanks get flooded and waste goes into the streets and streams, it can carry a lot of disease, including cholera, dysentery and typhoid.

The problem is that the world has only one gold standard for sanitation, which is having flush toilets connected to sewer lines, that are further connected to big and expensive wastewater treatment plants. Growingcities that already have water shortages may not have enough water for everybody to bathe and cook, let alone to flush toilets. So, are these cities going to follow the same path we have taken for the last century in developed cities?

Spending on sewer systems and treatment plants would be as bad an idea as building a new coal power plant. You are committing to the next 50 years and if you are going to have an infrastructure that requires a lot of water and electricity, you are only making your city less resilient in the face of climate change.

What does the Gates Foundation suggest to address this problem?

We are working with partners to try and invent another gold standard for sanitation, one that does not require connection to a water line, a sewer line or an electrical line. Our Reinvent the Toilet Challenge is pushing to build toilets that are their own treatment plants, only powered by what users deposit into them. We gave grants to over 15 candidates and what we have now are a growing number of university partners who are proving they can kill all the germs in the waste so that what comes out is safe to handle. We have a couple of prototypes undergoing field testing — one was designed by the California Institute of Technology (Caltech), and a second one by Loughborough University in the United Kingdom.

How would these toilets work in a disaster setting?

We were very concerned after the earthquake in Nepal that if the sanitation system broke down, you would have a second wave of people getting ill and hurt. If we had these technologies ready then, you could imagine shipping in a lot of portable technology that has the ability to treat waste. These toilets don’t depend on having a pit or a septic tank, so they would also be more robust in the face of flooding.