Is Drinking Water Killing the Environment?

By: Carolina A. Martinez

Currently, 20% of the U.S. population gets their water cleaned by small drinking water systems and rely on disinfection methods to make the water safe for consumption. The issue is that the impact methods, like chlorine and ultraviolet (UV) disinfection, have on the environment have not been fully explored. In this study, the effects that those methods have on the environment were investigated while also taking into consideration the health effects that they have on humans; which are mainly caused by the carcinogens that are produced by the use of chlorine, the main disinfectant method for most water systems. 

The way this was studied was by comparing three typical water scenarios. One that uses filtration, UV disinfection, and chlorine addition, one that uses only filtration and UV disinfection, and one that uses only UV disinfection and choline addition. 

Parallel coordinate plot showing the environmental impacts in all categories for the first typical source water scenario’s six chlorine disinfection alternatives with different contact zone materials and three UV disinfection alternatives with different validation factors. (Jones et al., 2018)

In the end, it was found that the method that had the overall lowest impact on the environment was the one using chlorine disinfection, but as seen in the figure, this is only true when it was held in plastic or concrete tanks. UV lamps were the best for health (no carcinogens produced), but it produced the largest impact on the Earth because of the high energy demands from the lamps and from the production of their electronic components. Using UV disinfection was only preferred when it was utilized with chlorine but with out filtration. UV was also recommended for use when water treatment facilities have issues with high amounts of pollutants caused by the chlorine. With this information, utility companies can pick the water treatment method that is environmentally friendly and healthy for humans. 

Reference

Jones, J.H., E.G. Shilling, K.G. Linden, and S. M. Cook. 2018. Life Cycle Environmental Impacts of Disinfection Technologies Used in Small Drinking Water Systems. Environ. Sci. Technol. doi: 10.1021/acs.est.7b04448