The Western United States has always been dry; San Diego, for example, derives only 15% of its annual water needs from rain.1 Engineers have constructed creative but short-sighted solutions to the problem of water shortage in response. Rivers have been diverted hundreds of miles to major cities, enabling further urban growth in areas that would otherwise not be able to support it.2 This rapid growth, however, comes at the cost of depleting these rivers. Letting entire cities, such as San Diego, Las Vegas, or Phoenix wither away is unrealistic, so scientists must create solutions that are sustainable, environmentally friendly, and relatively easy to implement in order to facilitate the survival of the Western states. Enter the concept of recycled water. Known as “toilet to tap” by its adversaries, recycled water is wastewater that, once cleaned of pathogens, viruses, pharmaceuticals, chemicals, and biological matter, is redistributed as drinking water. In order to sustain the existence and growth of Western cities, recycled water must be accepted and utilized.

To understand the need for recycled water, it’s helpful to look at the typical water shortages in the Western United States. Since 1950, there has been a 127% increase in water use nationwide, putting extreme strain on the existing infrastructure and environment.2 This increase in water usage has occurred despite the worsening droughts that affect the area. Studies conducted in Salt Lake City show that an increase by even one degree Fahrenheit causes as much as a 6.5% drop in local stream water flow per year.2 The increase in temperature will also strain and eventually exhaust the sources from which Western cities get their water. The West is faced with an issue that few wish to confront: if they continue to rely only on traditional water sources, Western cities will literally dry up, forcing residents to move elsewhere and creating massive economic instability nationwide.

One possible solution to water shortages is recycled water. The process of recycling water is intensive, which is understandable given the dangers of contamination. Wastewater is first sent to a sewage treatment plant where filters remove solids and dissolve biological material.3 The wastewater then undergoes normal groundwater treatment. First, microfiltration removes bacteria and protozoa. Then, reverse osmosis is utilized to remove viruses, salts, and pharmaceuticals. Finally, ultraviolet light and hydrogen peroxide destroy “trace organics.”3 After these steps are taken, the treatment plant adds in minerals and discharges it into a reservoir. Months later, the water from the reservoir is treated again and distributed to households.

It is a subject of debate whether water is clean enough after the treatment to be directly distributed without mixing it with reservoir water. Some say that the water produced by the treatment plant is even purer than reservoir water.4 Others, however, say that directly releasing treated water into the reservoir instead of letting it percolate through various ground layers permits impurities to remain in the water.5 Whether the water is safe enough to be directly consumed depends on the regulatory standards themselves as well as the plant producing the water. When produced according to Environment Protection Agency (EPA) guidelines, recycled water is as safe as traditionally obtained water.6

Another concern about recycled water is that treatment plants are unable to entirely remove pharmaceuticals, chemicals, and bacteria such as E. coli. The presence of E. coli could be the result of organic material remaining in the water after treatment. Traces of pharmaceuticals also pose a risk to the consumer. When medicine is flushed down the toilet or sink, it remains in the water supply and can be redistributed to other consumers. Although studies do not deny claims that such trace pharmaceuticals are found in recycled water,7 it is important to put this into perspective: even non-recycled water contains trace amounts of pharmaceuticals and is deemed safe for public consumption by the EPA.

Furthermore, many scientists who were once wary of recycled water have changed their opinions. In 1998, the National Research Council (NRC) reported that discharging recycled water into reservoirs was acceptable, “although only as a last resort.”1 Many people opposed to water reclamation cited this study, emphasizing the fact that it should only be used as a last resort, and not otherwise. The Western states are, however, facing water shortages that will soon require last resorts. More importantly, however, is the NRC’s new statement about wastewater treatment technology: “the possible health risks associated with exposure to chemical contaminants are minimal.”6 Thus, those opposed to recycled water cannot continue to use the NRC’s previous stance as backing for their claims. Recycled water that adheres to the EPA’s health and safety guidelines is necessary for the survival of states in the Western U.S.8

In addition to safety, cost is also an important factor to consider in the production of recycled water. Currently, the production of recycled water is not subsidized by the government. Due to the additional treatment that waste water requires, the production and distribution of recycled water costs four times more than that of groundwater.1 If recycled water were to be subsidized, as it is in Orange County, water production would cost only 0.0018 cents per gallon to produce, a small increase from traditional tap water’s cost of 0.0015 cents per gallon.1 With the U.S. government’s support reclamation plants in the West, the prohibitively high cost would no longer be an issue. Even if recycled water were not subsidized, the added cost could provide long-term societal benefits. By increasing the cost of tap water by introducing government recycling, thus moving the cost from taxpayers in general to those who specifically use the water, cities could decrease water use over time. Residents would, if confronted with rising water prices, make an effort to consume less which would decrease stress on the treatment plants themselves as well as natural resources.

The biggest challenge to recycled water, however, is not its cost or purported health risks, but rather its public perception. The unflattering name, “toilet to tap,” hardly brings to mind the sparkling springs associated with “safe” bottled water. There are large groups of detractors who state that recycled water can’t be trusted, and to some extent, they have reason to maintain this stance. In the past, recycled water facilities released non-potable recycled drinking water in four cities.5 Although this potential issue cannot be ignored, the benefits of recycled water when it is produced in a fully functioning facility with enforced safety standards cannot be ignored either. These isolated incidents do not indicate that all recycled water is unsafe, but rather that it must be better regulated.

Despite a number of vocal public groups in opposition to recycled water, there is growing support for the construction and utilization of reclamation facilities. In San Diego, a 2004 poll revealed that 63% of citizens opposed water reclamation; in 2011, this number dropped to 25%.1 Education is the most influential method for obtaining a higher proportion of positive response. The most common objection to using recycled water revolves around the concept being “disgusting.”4 For many, the phrase “toilet to tap” induces an image of the contents of a toilet bowl flowing directly to their kitchen sink. When they are shown the intensive treatment process, though, they understand that the water is safe to drink and environmentally friendly. About 95% of people who have taken tours of the water recycling agree it is feasible.3 If people in the Western states and nationwide are exposed to the method in which wastewater is treated, recycled water may gain popularity.

Recycled water, if able to defeat the social stigma that surrounds it, could be a literal life-saver in the Western United States. While Los Angeles shut down a reclamation facility built in 2002, there has been an effort to reopen it. Doing so could reclaim 9.7 billion gallons of water per year.9 While recycled water cannot supply cities like Los Angeles with all the water they need, it is a step in the right direction. By increasing the cost of water to a level where overuse would be discouraged and by instituting water reclamation facilities, the cities of the Western U.S. may be able to survive. The major obstacle to the implementation of recycled water is public disapproval due to ignorance about the process of water recycling and the purity of the final product. However, if educated about the process of water recycling, the public might come to see reclaimed water as a safe and effective water source.


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