One of the topics my group is considering is water scarcity. This article discusses the possibility of using direct potable reuse as a possible method of addressing water scarcity. DPR is the process of treating wastewater to drinkable standards and returning it directly to the water supply rather than through a buffer such as a reservoir. While Windhoek, Namibia is currently the only place that does DPR the technology is there to return wastewater back to almost distilled water quality. The process involves starting with microfiltration which removes large particles, then passes through a reverse osmosis system, and finally ultraviolet light and hydrogen peroxide which kill all final bacteria. DPR allows communities to reuse water locally and it provides a viable vehicle to help address water scarcity.
One problem that DPR currently faces is that there are no national regulations for water reuse. Establishing a regulatory system around water reuse could help reduce some of the suspicion surrounding the reuse and treatment of wastewater into drinking water. As the article pointed out one of the key things is to focus on the water quality rather than where the water comes from. After all, it may be possible for the treated wastewater to be better than some of the water that is making its way into the houses of millions of Americans.
http://www.waterworld.com/articles/print/volume-29/issue-9/editorial-features/battling-water-scarcity.html