The invention of modern plumbing systems revolutionized human civilization. Without some form of plumbing and sewer systems, humans would not have been able to build cities. Without pipe systems to transport water and waste, we would still be confined to areas near rivers, lakes, and other water sources. The implementation of sewer systems separate from living areas caused a huge decrease in disease and infections and allowed for the adoption of more hygienic attitudes and antiseptic practices, as people were no longer inhibited by the human waste surrounding their homes and infecting the water supplies. Developing plumbing and waste management systems has been key to human expansion, both physical and societal, for centuries, dating back to ancient Mesopotamia, Minoan, and Roman civilizations and continuing into the present day. Innovation in this field of waste management is integral in our struggle towards a more sustainable and zero-waste society. The San Francisco-based water recycling company Epic CleanTec incorporates this philosophy in its mission of reducing water waste via decentralized, on-site water treatment, recycling, and energy recovery.

San Francisco (and many surrounding counties) sources its municipal water from two watersheds, the Tuolumne watershed and the Alameda and Peninsula watershed, but about 85% of San Francisco’s water supply comes from the Hetch Hetchy reservoir in the Toulumne watershed. Hetch Hetchy is a glacial valley, reservoir, and water system located in Yosemite National Park. The water from Hetch Hetchy reaches the Bay Area through a 167 mile long underground aqueduct. Due to geographical and ecological factors as well as strict legal protection of the reservoir, the water is considerably extremely clean, making San Francisco one of six US cities not required by law to filter its tap water. While this is a remarkable resource, it does mean that fresh, potable water is being transported all the way to the Bay to be used in non-potable contexts, such toilet water or laundry water. Each time a toilet is flushed, new, fresh, drinkable water is used to replenish it. This issue is one of the several focuses of Epic CleanTec’s operation.

Founded in 2015, the concept for Epic CleanTec was born from the “Reinvent the Toilet Challenge” hosted by the Bill and Melinda Gates Foundation. Epic CleanTec describes itself as a “full service water technology company” whose sustainable water treatment and recycling systems reduce the cost and complexity of managing such systems for building owners as well as reduce the strain on municipal water supplies. They achieve this by operating on-site water treatment and reuse systems in individual buildings or groups of buildings to convert building wastewater into treated water for non-potable applications (toilet water, etc), natural soil additions (compost), and recovered wastewater heat energy. According to the Epic CleanTec website, their technology results in up to 95% reduction in water demands and utility fees. 

On March 30th, I visited an Epic CleanTec facility as part of a field trip with my Health and Environment class. Before we began our tour, my classmates came up with three environmental science-related focus questions to guide our experience on the tour: firstly, how does Epic CleanTec source water sustainably? Secondly, is any waste created by the treatment process, and if so, what is done with this waste? Finally, what precautions are being taken to ensure sustainability and prevent waste?

The facility itself was actually located in the basement of a 40-floor luxury residence building near Civic Center, the Fifteen Fifty. Epic CleanTec’s CEO, Aaron Tartakovsky, was kind enough to direct our tour! He was very knowledgeable about all of the processes involved and was able to answer everyone’s questions with detail and confidence. We began in the opulent lobby of the Fifteen Fifty, taking the remotely controlled elevator to the basement. The first sector of the facility we visited was the water collection tanks. There were two underground tanks, one collecting all the greywater produced by the building and the other collecting the building’s blackwater. For reference, greywater is the water that drains from showers, sinks, kitchens, and laundry machines, while blackwater is water that contains human waste, i.e. toilet water. There was also a valve that was labeled “sewer.” Tartakovsky explained that this pipe was their “emergency backup” so that when the tanks were nearing capacity, some of the collected wastewater would automatically be diverted to the municipal sewer system. He also revealed that they use this mechanism every day, which could call into question the efficacy of this program, as well as highlight the high level of water usage in luxury highrise buildings.

The second sector we visited was where the actual water treatment process happened. It was a separate room in the basement with about three or four large, above-ground, high-tech-looking tanks, named OneWater systems, all connected by various pipes. The multi-step filtration, treatment, and sanitization process was laid out by Tartakovsky: water from the initial collection tanks are prefiltered twice to remove the major solids, which are then diverted to the municipal sewer or sequestered, dehydrated, and taken to the secondary facility where it is turned into compost! The water is then “biologically treated,” which is a very interesting process in which the water undergoes anaerobic fermentation (like digestion) via microorganisms supplemented in greywater or sourced from biotechnology companies. This further removes any organic material from the water. The water is then pushed through a series of membranes with diameters of only 0.04 microns to ensure there are no solids left in the water. Finally, the water is sterilized and disinfected using chlorine, ultraviolet light, and carbon filtration. If any heat energy is used during the process, the system recaptures it and uses it to preheat domestic water for the building, thus saving energy costs and creating a closed loop for heat energy waste. This whole process creates clean water that is perfect for reuse in toilets, urinals, and laundry machines. Using water from the building itself is where the recycling aspect comes in, and is a fantastic step towards closing the loop for water waste.

The next stop on our tour was a building down the block, where another OneWater system was installed. This location also included a very special stop: a small garden in the back of the building where everything was grown with Epic CleanTec’s compost by-product. It was really cool to see the physical product of this company’s zero-waste attitudes and goals, and I thought it was a very smart way to repurpose waste that no one thinks about.

A concept brought up by Tartakovsky throughout the tour was their dedication to challenging what they coined the “flush and forget” mentality. Initiatives in overlooked areas like waste management are so necessary in our ever growing and ever-adapting society; Epic CleanTec is making momentous steps towards more responsible and sustainable water practices. However, there are some issues with access; the facilities so far are only in luxury apartment buildings, and the garden is hidden away behind tall fences. Of course, the major limiting factor for dispersing this technology is policy and regulations, but it would still be majorly beneficial to incorporate this kind of water recycling technology in municipal buildings as well, such as schools and offices.

Wastewater sample compared to the clean, treated water sample.

Source: Epic CleanTec


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