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How the water you flush becomes the water you drink - Francis de los Reyes


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In 2003, Singapore’s national water agency launched an unprecedented program to provide more than 50% of their nation’s water supply by recycling wastewater. The program had been planned for decades to ensure the island nation never ran out of clean water. But is it really safe to reuse anything we flush down the toilet? Francis de los Reyes explains the science of wastewater treatment.

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Reusing our wastewater actually happens all the time at larger scales. The wastewater from a town or city may be discharging to a lake or river, and another town downstream may be using the same lake or river as a drinking water source. Thus, “indirect reuse” is happening all over the world. However, the direct treatment of wastewater to make it a drinking water source is needed today more than ever. 

In 2014, in response to a 40-year drought, the town of Wichita Falls in Texas started piping 5 million gallons a day of treated wastewater into its water system. For about a year, until the rains came, the residents of this Texas town were drinking their wastewater. The NEWater project in Singapore, which began in 2003, is widely known as a success, and continues to augment the country’s water supply. In the US, the City of San Diego has been at the forefront of research and the pilot testing of indirect and direct potable reuse to reduce its dependence on imported water from the Colorado River and Northern California. 

In California, indirect potable reuse of wastewater (groundwater replenishment or reservoir supplementation) is tightly governed by U.S. EPA and CA rules and regulations. This ensures that chemicals such as 1,4-dioxane and PFAS (perfluorinated alkyl substances) are below maximum contaminant levels or notification levels set by the state. Water reuse can also happen in non-sewered situations (i.e., household or onsite systems). Research is being conducted on treatment options, risks to humans, and life cycle assessment. In the U.S., a national water reuse action plan is coordinated by the U.S. EPA. Many organizations, such as the WaterReuse Association are dedicated to advancing policies, laws, and public acceptance of water reuse. A big challenge is educating the public, and community-based educational campaigns have proven to be critical in that important effort.

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Meet The Creators

  • Educator Francis de los Reyes
  • Director Jody Ghani Nordby
  • Narrator Addison Anderson
  • Music Salil Bhayani, cAMP Studio
  • Sound Designer Nirana Singh, cAMP Studio
  • Producer The Animation Workshop, Anna Bechtol, Sazia Afrin
  • Director of Production Gerta Xhelo
  • Editorial Director Alex Rosenthal
  • Editorial Producer Dan Kwartler
  • Script Editor Dan Kwartler
  • Fact-Checker Charles Wallace

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