Team:Virginia/WasteWaterEveryday
There is WHAT in your drinking water?
So, you’re curious, could you really be drinking some of TJ’s piss? Well, not exactly, but we’ll get to that. Just remember that water is constantly recycled, and thanks to sanitation processes, we can turn wastewater into clean drinking water.
What is wastewater, you ask? Really anything that goes into a sink, drain, or toilet (you do your thing baby!)
The Rivanna wastewater treatment plant services the water coming out of this bathroom. The plant serves over 110,000 residents in Charlottesville and Albemarle county more generally. Over 10,200,000 gallons of wastewater are treated per day!
As you sit here, it might seem obvious why we need to clean wastewater. It’s not a new idea either; in fact, archaeologists have uncovered a well-coordinated sewer and drainage system from the Minoans and Indus valley civilizations dating back as far as 3000 BC.
The Romans were pioneers in the development of sewerage systems. Under the reign of Tarquinius Priscus in 616BC, the Romans constructed the Cloaca Maxima, which removed wastewater, rainwater, and swamp sewage. This massive freshwater channel drained into the Tiber river and illustrated then state of the art hydraulic engineering and architecture.
Unfortunately after the fall of the Roman empire, progress in sanitation and sewage systems was sluggish until the 18th century. This is where Mr. Jefferson comes back into play. In the newly formed United States, sanitation was a private property priority. Cesspools and privies were largely used to remove human waste, but busy with colonial expansion and a small thing called the American Revolution, the United States had bigger problems on their dirty hands.
A Cholera epidemic in Paris around 1830 and several breakouts in London inspired a renewed focus on sewage treatment. Cholera is one of many bacterial pathogens originating in untreated wastewater from the bacterium Vibrio cholerae. Enter Claude-Philibert Barthelot, Henry Charles Emmery, and Georges Haussman, the men responsible for the introduction of underground gutters and over 600km of of new pipes and ducts in Paris.
For reference, 200 years after the first Cholera outbreak of 1817 in the delta of the Ganges, India, the pathogen still claims 143,000 lives each year. As reported by WHO, nearly 4 million people were infected in 2017, predominantly in third-world countries.
Beyond human health, though, untreated wastewater can have destructive effects on our environment, and for endless seafood and sushi buffets everywhere. It’s called eutrophication. Think of it as death caused by indigestion, like eating too much at, oh I don’t know, a sushi buffet and regretting it forever. Let us explain. Eutrophication is human-induced nutrient enrichment of surface water, which seems harmless at the surface (hehe corny I know but we had to). All of these extra nutrients, like nitrogen and phosphorus, feed the rapid growth of species of algae and zooplankton.
As these populations rise, their oxygen demand increases. These species vanquish the water of its dissolved oxygen (DO) to levels that are dangerously low for the fish and flora below. And then, like using a bug zapper in a small lake, you get fish kills like this one in Wisconsin.
Over time, eutrophication can induce dead zones where DO concentrations remain at less than 1 mg/L. Thankfully, we’ve made strides in reducing dead zones. One primary reason for this has been improved wastewater treatment facilities. If you’re still sitting, don’t get up! While you finish your business, let us finish our’s. This is where it gets really interesting.
When you flush this toilet, everything in it will make its way through the sewer system and deposit at the Rivanna Wastewater facility as previously mentioned. From there, the wastewater goes through a primary clarifier that removes most solids.
The Bardenpho process, a modern method for Biological Nutrient Removal (BNR), follows. Trying to envision this process? Imagine Willy Wonka’s Chocolate river, but...smellier. Bardenpho uses bacteria to remove phosphorus and ammonia (those extra nutrients we talked about) via anaerobic (no oxygen present) and aerobic tanks. For wastewater plants as large as Rivanna, the infrastructure for this process can cost upwards of $25 million.
Nearly 50% of some plants energy costs come from aerating during the Bardenpho process. Our synthetic biology project hopes to revolutionize BNR. If you’re interested in finding out more about synthetic biology and how our team is revolutionizing the Bardenpho process, check out this link.
After the Bardenpho process, a secondary clarifier removes any remaining solids. Then a sand filter purifies the water, and finally, high-energy UV light is used to kill any bacteria still living in the water. Consider this UV disinfection like a really bad sunburn. This clean water is returned to the environment, but don’t worry. It’s not quite ready for drinking. That’s another story entirely.
Thus brings us back to Mr. Jefferson. While it is theoretically possible some water molecules in your morning coffee once passed through TJ’s own homebrew, I wouldn’t sweat it.
Thank you for reading! We hope this site gave some purpose and some fun to your...er business at hand. Best of luck finishing up! We encourage you to check out our Virginia iGEM facebook page, as we will continue to track our progress. Have a great day!
Oh, and one more thing, remember to wash your hands!
References:
De Feo, Giovanni, et al. “The Historical Development of Sewers Worldwide.” Sustainability, vol. 6, no. 6, June 2014, pp. 3936–74. www.mdpi.com, doi:10.3390/su6063936.
“WHO | Cholera.” WHO, http://www.who.int/mediacentre/factsheets/fs107/en/. Accessed 2 Nov. 2017.
Zapfd09. “The Endolymph: Phosphorus in Wisconsin.” The Endolymph, 15 Apr. 2011, http://endolymph.blogspot.com/2011/04/phosphorus-in-wisconsin.html.
Nutrient Removal Is Bardenpho Right For You. https://www.wateronline.com/doc/nutrient-removal-is-bardenpho-right-for-you-0001. Accessed 2 Nov. 2017.
