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Facing the Yuck Factor

How has the West embraced water recycling? Very (gulp) cautiously
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By Peter Friederici

High Country News

Sometime this fall, Mike Nivison plans to take a healthy swig of water that exemplifies everything you'd expect from a small resort town set high in a Western mountain range. The water will be cool, clear, refreshing. But it won't be pristine spring water pouring from some mossy crevice.

Nivison is Cloudcroft's village administrator, and what he anticipates savouring will come from the village's drinking-water treatment plant — and, not too long before that, from its sewage treatment facility.

Cloudcroft's will be one of the first wastewater systems in the United States to allow — or require, depending on your perspective — residents to drink treated wastewater that hasn't been naturally cleansed in a river or aquifer. It will be built entirely as a matter of necessity. At an elevation of more than 8,500 feet in southern New Mexico's Sacramento Mountains, Cloudcroft is high and, thanks to recent years of drought, dry.

"A city like San Diego can go buy more water," says Bruce Thomson, a University of New Mexico civil engineer who has been helping Cloudcroft develop its new water system. "It's expensive, but they can. But Cloudcroft is simply out of water. Because they're at the top of the mountain, there's no new place to drill wells. They're at the top of the watershed. They don't have any other alternatives."

Cloudcroft has only about 750 residents, but its population swells to a few thousand on summer weekends. All those people escaping the lowland heat can use more than a third of a million gallons of water on a single hot Saturday. But the village's major wells produce only about 150,000 gallons a day. To make up the shortfall, village officials have resorted in recent years to hauling water, which is expensive, inconvenient and energy-intensive.

Nivison figured that Cloudcroft's only sure source of what he calls "wet water" — that is, usable liquid, rather than theoretical legal rights or hard-to-reach water that might be buried somewhere deep underground — was right at his feet, in the stream of effluent pouring from the village's wastewater treatment plant. With several million dollars in state funding and the help of engineers from two universities and a private firm, the village has been building a plant to purify that water. After conventional treatments that settle solids and utilize microbes to degrade or remove pathogens, the plant will use multiple filtration methods, including reverse osmosis, to remove chemical contaminants. Then the water will be sent to covered tanks and mixed with groundwater pumped from the village wells.

After three or four weeks, the blend will be sent back through drinking-water treatment and distributed for use. The wastes squeezed out during the reverse osmosis process, meanwhile, will be concentrated in briny effluent, which the village will store for use in dust control on roads, fighting fires, and, possibly, for making artificial snow at the local ski area.

And then the toilets will flush, and the sinks and tubs will drain, and the cycle will repeat again — and if Nivison and his collaborators are lucky, no one will think much about it.

"By any parameter you can measure — suspended particles, salts, bacteria, pharmaceuticals — the water from this process is going to be extraordinarily clean," Thomson says. "But you have to overcome the 'yuck factor.' It's not measurable, it's not quantifiable, but it's every bit as important as the particles you can measure."

"All we've done is recycle the same water on this earth since the beginning of time," Mike Nivison says. "This is just a more controlled environment for doing the same thing. I do believe this will be our salvation."

As the West grows in population, and as climate change seems to be decreasing the reliability of some water supplies, some of the region's residents are reconsidering the notion that effluent is something to get rid of as efficiently as possible. Only a few are willing to go quite as far, yet, as Mike Nivison, but many are at least embracing the idea that wastewater is a valuable resource. What's happening in Cloudcroft, then, is a portent of what is happening, and what likely will happen, in other arid places.

But the prospect of brewing your morning coffee with water that was recently washing greasy dishes or flushing a neighbour's toilet has many people uneasy, and not just because of what psychologists and water engineers alike call the "yuck factor." The water to be recycled may carry a host of pollutants, some recognized only recently. Among the most worrisome are endocrine disruptors, which pose potentially large but as yet incompletely proven health threats that are making some scientists very nervous.

San Diego’s problem

Twice in the last 10 years, San Diego city officials have proposed augmenting the city's drinking water supply with water reclaimed from the city's sewers — and twice, in 1999 and again last year, those plans have been shot down.

It is a telling comment on the disjointed nature of much water management in the United States that San Diego has both a water-supply and a water-disposal problem. On the supply side, the city imports between 85 and 95 per cent of its water from distant sources — specifically, from the Colorado River and the California State Water Project, which conveys water from Northern California to the state's dry southern half. Those sources have historically been reliable, but only up to a point. In 1991, during a severe drought, water project deliveries were on the verge of being drastically cut when the rains finally came; this year, water planners are asking users to make voluntary cutbacks. And current climate projections suggest that the flow of the already over-allocated Colorado River may decline significantly in the future.

For wastewater disposal, San Diego relies on a water-treatment plant at Point Loma whose technology is antiquated. It discharges effluent that does not meet Clean Water Act standards into the Pacific. San Diego has a waiver from the federal Environmental Protection Agency allowing it to dump that effluent, but the waiver expires in 2008. The cost of upgrading the Point Loma facility to meet EPA standards has been estimated at $1 billion, and the city has yet to make plans to raise that money.

As part of a settlement agreement stemming from a lawsuit by the EPA and environmental groups, San Diego agreed to reduce its effluent discharge into the ocean by building two plants to treat water for reuse in the city and its surroundings. Those plants are now capable of putting out 37.5 million gallons of reclaimed, non-potable water a day.

Like many other municipalities in the West, San Diego sells some of its reclaimed water to buyers who use it to water golf courses, feed industrial processes, and flush toilets. It's distributed in a network of purple pipes to distinguish it from the potable water supply, and it's currently available at about a third the cost of potable water. The trouble is that the purple-pipe network amounts to an entirely new, parallel water system, and San Diego, like many other cities, hasn't extended it very far.

"It's expensive to pay for the distribution of recycled water," says Maria Mariscal, senior water resources specialist for the San Diego County Water Authority. "Installing purple pipe in new developments is OK, but retrofitting in established areas can be expensive."

As a result, the city is able to sell only about a third of its recycled water capacity and is unlikely to meet its target, developed as part of the lawsuit settlement, of selling at least 50 per cent by 2010.

To figure out how to use more of the reclaimed water, the city Water Department conducted a study that recommended treating it intensively and returning it to the potable water system. The system would be like Cloudcroft's on steroids: 16 million gallons a day rather than 100,000. Using the treated water to supplement San Diego's drinking-water system at a single point would be much more cost-effective than piping the treated water to an entire network of dispersed users of non-potable water.

Turning treated effluent into drinking water is a widespread practice. It's most commonly done when communities dump their effluent into streams and rivers, knowing that other users downstream will use the same water. But an increasing number of communities are reusing their own water. In Orange County, El Paso, Tucson, and many other Western communities, water agencies recycle by dumping treated effluent on the ground so that it can soak in and recharge aquifers. After that water's been underground for a while, it is then pumped up for drinking water use.

San Diego's topography, though, doesn't lend itself to recharging water from the treatment plants into local aquifers. So planners proposed pumping the treated effluent into a reservoir that feeds the city's drinking water system. The city council's Natural Resources and Culture Committee agreed and forwarded the proposal to the full council. A wide range of stakeholders on a community panel agreed, too.

"To me, this is a win-win," says Bruce Reznik, executive director of San Diego Coastkeeper, an environmental group that monitors coastal pollution. "You're discharging less into the ocean, and you're creating a local water supply that you otherwise wouldn't have."

But opponents exploded, labeling the idea with a visceral and unforgettable moniker of the sort no politician can afford to ignore. "Your golden retriever may drink out of the toilet with no ill effects," editorialized the San Diego Union-Tribune under the headline "Yuck!". "But that doesn't mean humans should do the same. San Diego's infamous 'toilet to tap' plan is back once again, courtesy of Water Department bureaucrats who are prodding the City Council to adopt this very costly boondoggle."

Mayor Jerry Sanders came to much the same conclusion, announcing in July of last year that he would not support the reservoir augmentation plan. A year later, the city council has yet to decide on any new wastewater reuse strategies.

"It was certainly disappointing," says Jim Crook, a consultant who helped draft California's water-reuse guidelines in the 1970s and served on an independent task force evaluating the city's proposal. "It was a good project from a technical standpoint. We were very comfortable with what they were going to do. The reclaimed water would be of a higher quality than some of the raw water sources that are used now."

That, indeed, is one of the principal ironies here: Before it could even be used for reservoir augmentation, the water would be treated to a higher standard than what San Diegans are drinking now. Water discharged from the North City facility has already been shown to be at least as clean as water in some of the city's reservoirs. If it were to be dedicated to potable reuse, it would be subjected to further intensive treatment, such as reverse osmosis, before being pumped to the reservoir.

Reverse osmosis uses pressure to force water through a membrane that allows water, but not most other molecules, to pass through. Using it would bring San Diego's erstwhile wastewater up to a much better quality than, say, the Colorado River, which receives the waste from hundreds of municipalities and industrial users by the time it reaches Southern California. Las Vegas alone discharges roughly 60 billion gallons of wastewater a year some miles upstream of its own water intake — a feat of urban engineering that would seem to prove that most of what happens in Vegas really does stay there. What happens in Sin City is fueled by prescription and over-the-counter pharmaceuticals, caffeine, sunscreen, synthetic compounds used in plastics and detergents, and even methamphetamines, say researchers who have found all that in Lake Mead's water.

Las Vegas' effluent is diluted as it flows downstream, and some of the compounds in it are degraded by sunlight, destroyed by microbes, or bound up in sediment. Still, monitoring in 2006 showed that water entering San Diego's municipal system contained, before drinking-water treatment, small but measurable quantities of ibuprofen, the insect repellent DEET, and the anti-anxiety drug meprobamate.

"We can have a lot more monitoring and control if we oversee our own reclamation than if we're relying on a river with a billion gallons of recharge from other sources every day," says Bruce Reznik.

History matters

In Windhoek, Namibia, water from a wastewater treatment plant is piped right back into the drinking-water system. NASA is developing advanced recycling technology that will directly convert astronauts' urine into clean drinking water. Such reuse systems are what a South African pioneer in water reclamation, Lucas van Vuuren, was thinking of when he said, "Water should be judged not by its history, but by its quality." Sufficient treatment, he meant, assures that any water can be reused.

Van Vuuren's is a technocrat's line, though, because in fact most people's tools for judging water quality aren't up to the task. Conventional wastewater treatment is very good at removing the kind of contaminants people can detect without laboratory equipment, such as odours, suspended particles, and the sorts of bacteria that can cause illness. But most people are relatively helpless when it comes to making more detailed assessments of their water supply's safety. The lower Colorado River looks clean enough; it's more likely to meet most people's standards than cleaner water in a pipe outside a complex-looking treatment plant.

As a result of that perceptual shortfall, people are left with nothing but water's history as a guideline, according to Brent Haddad of the University of California at Santa Cruz, an environmental studies professor who directs the university's new Center for Integrated Water Research.

A visceral aversion to unclean water, Haddad says, is an understandable and useful tool that served the human species well through most of its evolution. But it may not be particularly helpful today, when it's necessary to make a decision between two sources of water that are both clear and odourless — but from very different sources.

"When people are aware of the history of their water, it matters a lot to them," he says. "If there's an unavoidable link to prior urban use, that's troubling to people. It's extremely hard to convince people then that the treatment will be good enough to override that history. But people are willing to take Colorado River water or groundwater that's clearly been used by other cities because it's easy to abstract away that use and begin the water's history with its taking from the natural system."

Rivers and soils do, in fact, clean water. But the psychological cleansing they do may be equally important. As a result, even the Colorado River — however thoroughly dammed, diverted, and delivered through aqueducts it may be — appears more natural, and cleaner, to many people than what's produced by San Diego's wastewater treatment plants. The river takes the yuck out.

The largely unwelcome prospect of drinking treated effluent, though, forces people to ask what's in the water they're already getting, whatever its source. Something long taken for granted becomes a public issue. And as people debate where their future water supplies are going to come from, an increasing number of experts and nonexperts alike are growing increasingly alarmed about the chemicals flowing not only from Las Vegas, but from every community.

Wastewater engineers are rightly proud of what their industry achieved in the 20th century, bringing safe drinking water to virtually every community in the United States. But most wastewater treatment plants were not designed to remove the sorts of complex organic chemicals that show up in Lake Mead — or, to cite a more pristine-looking example, Boulder Creek, which tumbles out of the Rocky Mountains and through Boulder, Colo., before joining the South Platte River.

Back in 2000, David Norris thought Boulder Creek an unlikely place to look for unhealthy fish. Even below the city's wastewater treatment plant, the creek looked clean, and fish and other aquatic organisms lived throughout it. There was none of the stench, the brown murk, or the belly-up fish associated with the bad old days of piecemeal sewage treatment before the Clean Water Act was passed in 1972.

Norris, an endocrinologist at the University of Colorado — and an avid fisherman — had read studies in the scientific literature documenting the environmental effects of a poorly understood class of pollutants known as endocrine disruptors. Unlike many toxins, they didn't appear to be killing their victims outright. But in Lake Apopka, Fla., a pesticide spill had caused lingering reproductive failures and sexual abnormalities in alligators. In Britain, odd-looking fish that were not readily identifiable as males or females, but had sexual characteristics of both, were turning up in anglers' creels — especially in waterways below sewage outlets.

Norris and his colleagues, Alan Vajda and John Woodling, figured that Boulder Creek's best indicators of environmental quality were likely to be white suckers, a native fish that's widespread and not terribly finicky about water quality. "A good healthy freshwater stream has a good healthy sucker population," he says. "If you really disturb this species, you've really disturbed the ecosystem."

Norris had no trouble finding white suckers both upstream and downstream of Boulder's treatment plant. Upstream, everything seemed normal. Downstream, it was not. "Much to our surprise," he says, "we were appalled to see the extent of feminization in the fish population." He found five female suckers for every male; further, 20 per cent of the fish were "intersex" individuals showing characteristics of both sexes.

Alarmed, Norris looked for similar effects elsewhere, and found them. Fish below wastewater treatment plants in Denver and Colorado Springs showed some of the same symptoms. In the South Platte River, where Denver releases its waste, he couldn't find a single male sucker below the effluent outlet. Something in the effluent, it appeared, wasn't killing fish, but rather causing hormonal changes in them and producing female traits in male fish.

The evidence was circumstantial, though. Norris knew he had to more closely link cause and effect — which is hard to do in a natural setting, where fish in different reaches of the same stream might be feeding on different food, facing different temperatures, and otherwise dealing with widely variable conditions. So he and his colleagues have since built two "Fish Exposure Mobiles," which are basically mobile laboratories, built inside trailers, with fish-holding tanks. By pumping combinations of river water and wastewater effluent into the tanks on site, they're able to replicate the pollution concentrations fish face at various distances below treatment plants.

When they experimentally exposed fathead minnows — widely used as a test fish — to water like that below the Boulder treatment plant, Norris and his colleagues were able to feminize male fish within 14 days. They have since tested fish in other Colorado waterways below wastewater treatment plants in the Rocky Mountains and on the Western Slope. Data from those tests aren't available yet, but Norris will say that he is awfully worried in general about the presence of endocrine-disrupting chemicals in the environment, and in water specifically.

"It's fairly obvious that living populations are being subjected to far more chemicals in the last 30 years than when biological systems evolved, and so we wonder what effect that has on the genetic machinery," he says. "If we want to increase the use of wastewater, unless we're going to remove these compounds from the water, we're going to increase their concentration in the human population, since we're just going to be adding more of these compounds. We keep concentrating our population in cities, and as a result we're concentrating our effluent."

Endocrine disruptors

Most of the organic compounds that can disrupt the endocrine system are neither regulated by EPA standards nor often monitored in waterways or the drinking-water system. Few thought they were a problem until recently. But in a national survey published by the U.S. Geological Survey in 2002, researchers found such substances in 80 per cent of the waterways they sampled.

The endocrine system is essentially a complex signaling mechanism that tells genes and cells when to do what. It operates by means of chemical messengers, or hormones, that bind to certain receptors in cells. Unfortunately, many of those receptors aren't particularly picky. Receptors designed to react to the natural hormone estrogen, for example, can also be set off by a wide range of other compounds, from complex molecules that naturally occur in vegetables to synthetic chemicals found in soaps, plastics, pesticides, cleaning products and many of the other manufactured goods of modern civilization. They get into sewage when people urinate, or shower, or flush leftover pharmaceuticals down the toilet.

As in Boulder Creek, waterborne endocrine disruptors have in many places been shown to have harmful effects on aquatic organisms, especially fish. For example, male carp with unusually high levels of female hormones have been found in Lake Mead, where estrogen — the kind naturally produced in human bodies as well as the synthetic variety in birth-control pills — ends up when Las Vegans flush their toilets.

Hormones naturally work at very low levels; a human estrogen concentration as low as 1 part per trillion — so dilute that it's near the lower limit of what monitoring equipment can detect — has been shown to affect fish. The effluent dumped into Boulder Creek typically contains from 1 to 10 parts per trillion of human estrogen.

"People ask why such tiny levels have such a devastating effect," says Norris. "But that's the level at which hormones work. Parts per trillion is common stuff for an endocrinologist."

Consumers are used to thinking of drugs as having precisely tailored effects. But endocrine disruptors don't work that way. Because many different chemicals can activate a given set of hormone receptors, low doses of quite different substances can combine into a higher dose. That's one of the primary reasons a growing number of researchers worry about possible implications for human health.

Wastewater treatment lowers concentrations of most trace organic compounds — often by an order of magnitude or more — but it can't remove them all. As a result, effluent often contains a stew of complex chemicals. A recent U.S. Geological Survey study found that St. Vrain Creek, into which Boulder Creek drains, carries measurable loads of at least 36 different compounds, including artificial fragrances, fire retardants, antibacterial substances used in soaps, and substances used to manufacture plastics. The extent to which those chemicals work together to cause effects on the endocrine system — itself not well understood — is a big unknown.

"The endocrine system is much more than estrogens," says Catherine Propper, an endocrinologist at Northern Arizona University who has studied the effects of trace organics on amphibians. "We have this complicated endocrine system, and every time we find new aspects of it, we find they can be disrupted by some of these environmental contaminants."

It's difficult to draw lines of cause and effect between exposure to endocrine disruptors and human disease or disorder because people are exposed to so many chemicals from so many sources over many years, and because some effects may take years or decades to manifest themselves.

Of course, humans aren't exposed to the chemicals in effluent in the same way that Boulder Creek's white suckers are; we aren't swimming in the water 24/7. And by the time a creek, or the Colorado River, enters our faucets, the loads of trace organics poured into it from treatment plants upstream have been significantly reduced. But the intensity of water use in the West means that, in many river systems, water is taken in for further municipal use before natural cleansing mechanisms can do their full work.

"Our rivers and lakes do clean water, especially if they have long stretches between communities using it," says Theo Colborn, a longtime pollution researcher who runs the nonprofit Endocrine Disruption Exchange in Colorado and coauthored the 1996 book Our Stolen Future . "But we've exceeded their carrying and assimilation capacity."

When surface water is taken in for municipal use, it is treated with filtration and disinfection treatments that significantly reduce contaminant concentrations. But low concentrations of some compounds — often in the parts-per-trillion range — do remain to make their way into drinking water.

Some water experts argue that the amounts of endocrine disruptors people ingest in water are insignificant compared to those we get from other sources — plastic containers, foods, soaps, cosmetics, and many other products.

But some biologists argue that the cumulative effects of endocrine disruptors make it imperative to reduce their concentrations anywhere possible.

"You would have to drink incredible amounts of the water to amount to an effect that these chemicals naturally have," says David Norris. "But adult humans are getting estrogenic compounds from an incredible number of sources. So any amount we get from water will add to that, since these chemicals have additive effects.

The water-processing system has to balance needs and costs. People may choose to lower the quantities of trace organic compounds they ingest with their water, but they're going to have to pay to do so. And that means they'll have to consider how the risk represented by these chemicals stacks up against others.

"What's more risky, bridges falling or the water you drink?" asks Linton. "The utility folks are out there prioritizing what to spend money on. They may need to focus resources on putting a new pipe in rather than on removing a minuscule level of contaminants. There's a cost associated with all these things."

If consumers do decide they want to lower their exposure to trace organics, though, then water-reuse projects of the sort San Diegans have rejected, for now, may be a good way to go. Such projects are expensive, but they have the virtue of providing dual benefits: concentrations of contaminants that will probably be as low as feasible, and a reliable flow.

But the yuck factor will surely continue to be an issue water managers have to contend with. It seems to have deep roots in human history and perception, after all, and perhaps will be overcome on a wide scale only when it collides head-on with another deep-rooted but not always accurate Western perception — namely, that the water will always be there.

Peter Friederici teaches journalism at Northern Arizona University in Flagstaff. His latest book is Nature's Restoration (Island Press, 2006 ). This story first appeared in High Country News.



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