Sustainable groundwater treatment technologies for underserved rural communities in emerging economies.

Worldwide, about one out of two people depend on groundwater resources to satisfy their drinking water needs. While groundwater typically is of higher quality than surface water, pollution and geologic conditions may require treating groundwater to meet safe water quality criteria. Herein, a critical overview is presented of water treatment technologies for rural and underserved communities in emerging economies that depend on groundwater. Given that small to medium sized rural communities in emerging economies often lack the financial resources to support technologically complex and expensive centralized public water treatment systems, the focus is on proven technologies that are sustainable and acceptable by the rural population. After an overview of the underlying treatment mechanisms and the principal groundwater contaminants targeted by the traditional, advanced, and experimental water treatment technologies, we identify the groundwater quality parameters that may impact or interfere with the technology performance. We also introduce enabling environmental factors that might govern the implementation of water treatment technologies in the target communities and a brief discussion of safe storage of water after treatment to underline the importance of protecting the water from re-contamination. Our overview is further supported by tabulated summaries of the principal (dis)advantages of each technology covered herein, including cost considerations and social acceptance. Overall, our review suggests that underserved rural communities have sustainable and affordable options for cases where the quality of local groundwater resources requires treatment.