Tag Archives: Microfiltration

Future of global water conservation: sewage to treatment to tap

11 Jun
Lana Nasser is a junior studying public relations student at the University of Florida. She enjoys writing personality profiles, feature articles, blogging about skincare and beauty, and learning about the field of sociology.

Lana Nasser is a junior studying public relations student at the University of Florida. She enjoys writing personality profiles, feature articles, blogging about skincare and beauty, and learning about the field of sociology.

Editor’s note: This is part of a series of contributing bloggers beginning their careers as journalists/public relations professionals at the University of Florida. Please see my earlier post about getting journalists excited about science writing early on.

By Lana Nasser

The idea of drinking reclaimed wastewater may be off-putting to some, but as technology sophistication increases, people might not be able to tell the difference.

Due to the growing necessity for water in the United States and around the world, scientists are considering alternative and more sustainable methods of providing drinkable water, like reclaimed wastewater. Reclaimed wastewater is water that has undergone extensive treatment through advanced water technologies like reverse osmosis and multi-step filtration.

“Psychologically, a human being says, ‘Yuck! I don’t want to drink treated sewage,’” said Joseph Delfino, professor in the department of environmental engineering sciences at the University of Florida. “In most places where they get water out of a river, they’re already drinking water that has been through industries, people, animals, but we tend to disregard it.”

Currently, many scientists are studying public perception of recycled water.  Shane Snyder, professor of environmental engineering at the University of Arizona said that if people trusted the treatment process, they might understand that recycling water is unavoidable.

Professionals in the field, like Snyder, hope that public opinion will begin to change.

John Million, an environmental engineering graduate from the University of Florida agreed.

“There are technologies and practices that can take wastewater and treat it to be used again by humans,” he said.

How does wastewater become drinking water?

First, water undergoes advanced primary treatment, where it is separated from large particles. The water then goes into sedimentation tanks where chemicals are used to make scum rise to the top and primary sludge fall to the bottom. Once 80 percent of the solids have been removed and the water is separated, the wastewater is clean enough to be released into the ocean.

The second step is extensive filtration. During this step, bacteria are added to the primary treated wastewater. These bacteria help ingest organic chemicals.

Finally, the water is filtered again to remove any other remaining solids.  It is then disinfected with chlorine.

It is no secret that there are readily available technologies able to make reclaimed water drinkable through various procedures, but this expensive and energy intensive process raises questions of sustainability.

“If we throw enough money at it, we can treat anything to better water to drinking water quality. The issue is, is there a sustainable way to do it?” said Paul Chadik, associate professor in the department of environmental engineering at the University of Florida.

Due to the current need for diverse sources of potable water, some states around the nation are already drinking reclaimed water. The Orange County Water District in California opened a $480 million state-of-the art water reclamation facility in 2008. This facility is claimed to be the largest in the United States, and costs about $29 million a year to operate.

Resources that treat wastewater also require extensive backup systems in case of emergency.

“In our current system, if the plant were to break down, you would be able to drink it without having an adverse reaction. But if you drink wastewater that is improperly treated because the plant has broken down, it would be detrimental,” Chadik said.

In terms of reliability, Chadik believes that large numbers of efficient and readily available backup systems would be needed to take effect without delay in times of crisis.

In many places around the nation, precious resources like groundwater are being used for purposes in which treated wastewater could be used instead.

“Most of the drinking water we have is used to water lawns and flush toilets,” Chadik said. “That water doesn’t need to be very pure. It would be more sustainable to take our wastewater and use it to irrigate land that needs it.”

Americans spend billions of dollars every year treating water to drinking water quality when only about 10 percent of it is used for drinking or cooking. The rest of it is flushed down the toilet or drain.

The growing use of recycled wastewater for purposes such as irrigation, landscaping, industry and toilet flushing is an efficient way to conserve the fresh water resources we have left.

“Nature has done its thing historically for as long as the planets been around so things go up and down, but of course we’re here and we’re the one animals species that pays attention to things,” Delfino said.

Related links:

UF Water Reclamation Facility