Getting a Handle on the
Drought: From Waterless
Toilets to Fog Harvesting
BY GAR SMITH
Welcome to the Arid Era: it’s 2015 and drought is the new normal. Our reservoirs have become puddles. Our once-thick Sierra snowpacks have packed up and left. And the fastest growing crop in the Central Valley is . . . dust. But California is not alone. Around the world, cities in Africa, Asia, Australia, and the Americas are faced with rising human populations and dwindling water resources. More than 780 million Earthlings lack access to clean water: upward of three million people die annually from water-borne diarrhea, dysentery, and parasitic diseases. No surprise, then, that the World Economic Forum’s 2015 Global Risks Report lists water shortages as its top global risk.
Recent increases in global temperatures are only compounding pre-existing problems of water security. On an average day on planet earth, 17 billion gallons of drinking water are lost to aging infrastructure and inefficient, wasteful applications. “Many of our most important aquifers are over-pumped, and half of the world’s wetlands have been lost to development,” the Oakland-based Pacific Institute notes. The water-watching think tank adds that while “big dams and centralized storage projects have brought many benefits . . . ‘soft path’ solutions” are more resilient.
In January 2014—in the third year of a stillunbroken drought—Governor Jerry Brown called on fellow Californians to reduce water use by 20%. Given this challenge, what are the most promising “soft-path solutions” that will enable Californians to meet, and possibly exceed, this goal? Here is a short list.
Graywater Systems
Over the past quarter century, the population of Southern California has grown by four million, yet the demand for water has remained unchanged—thanks to various conservation measures. Californians use about 192 gallons of water per person per day. Watering lawns and shrubs consumes about four million acrefeet of water each year—43% of urban demand. (An acre-foot of water is about 326,000 gallons.) Letting the front yard go unsprinkled and the family car go unwashed is a good start. The next step could be installing a graywater system.
Graywater pipes can redirect 50% to 80% of the water from showers, bathtubs, and washing machines for use in irrigating outdoor gardens.
In California, any single-family home can use graywater for outdoor irrigation—so long as it is not used for root crops or edible parts of food that touch the soil. (Not permitted: socalled “blackwater” from dishwashers, kitchen sinks, and toilets.) A simple “laundry-to-landscape” set-up is easy to install, requires no state permits, and costs as little as $250.
Rainwater Harvesting
One quick-and-simple way to conserve nature’s cloudy bounty is to install rain tanks on your downspouts. The smallest system—using a 55-gallon drum—can capture 660 gallons a year, while larger polyethylene tanks can store up to 10,000 gallons. In California, the Pacific Institute estimates that “on-site rooftop rainwater harvesting for residential buildings has the potential to add between 30,000 and 145,000 acre-feet of water supply per year.”
Fog Catching
This low-tech form of water recovery has been around for 2,000 years. Back in the days of the Byzantine Empire, city dwellers erected stone cubicles to coax water from the air. Modern fog collectors using nets of cloth or metallic mesh are currently deployed in at least 17 countries.
In Flor de Amancay, a Peruvian city on the outskirts of Lima, four large fog-catchers produce up to 600 gallons of water a day. In Chile’s bone-dry Atacama Desert, billboardsized polypropylene screens can harvest 264 gallons per day. Fog-catchers in South Africa have captured as much as 1,000 gallons in a single day.
While traditional nets can only download 2% of the available water, MIT researchers have devised new nets that convert 10% of the fog into potable water.
There are some concerns: the durability of the nets and the impacts that placing nets on shorelines and coastal ridge tops could have, especially on redwood groves and wildlife that also depend on fog-delivered water. This would not be a problem, however, if the nets were deployed in an urban setting like “Fog City” San Francisco.
Green Infrastructure
Too much precious rainwater simply bounces off the cement-and-asphalt carapace of the modern city and washes away—laced with debris, animal waste, and toxic chemicals. Green infrastructure would render cities “rainfallfriendly” by building a variety of water catchments in the form of rain gardens, bioswales, permeable pavements, and green roofs covered with grasses and crops. A 2014 Pacific Institute study estimates that installing such “stormwater capture systems” in Southern California and the Bay Area “has the potential to increase water supplies by 420,000 to 630,000 acre-feet per year.”
Waterless Toilets
Each year in the United States, 2.1 billion gallons of the world’s most precious liquid are used, not to refresh thirsty crops or slake parched throats, but to flush human waste from toilets to municipal sewers. While harvesting rainwater and recycling graywater are fine strategies, there’s more water to be saved by getting to the seat of this problem. We need a Toilet Revolution.
Jeff Conant, author of The Community Guide to Environmental Health, has traveled the world in search of the perfect “waterless toilet.” He found one in the Mexican town of Tepotzlan, which boasts hundreds of nontraditional, waterless eco-loos.
While the use of human waste as fertilizer is an age-old practice, Tepotzlan’s eco-techs achieved an engineering Waterloo when they designed toilet seats that separate feces from urine. In the Tepotzlan toilets, fluids flow into a storage chamber while the solids drop into a dry compost toilet. One immediate benefit of separating pee from poo is the elimination of the unpleasant aromas associated with the traditional outhouse.
Today, “urine-separating dry toilets” are being adopted around the world, from South Africa, Peru, Cuba, and India to the United States, where composting waterless toilets can be purchased online. There are several to choose from, including Biolet, Envirolet, SunMar, the venerable Clivus Multrum, and the EcoJohn (an “incinerating toilet” that’s used in homes and US military camps). Home Depot lists a Biolet for $1,250 (about the price of a new fridge). The Nature’s Head urine-separating dry toilet (designed for use on boats) is currently priced at $925. Tankless toilets will start paying back the investment immediately as household water use typically falls by onethird.
By going off the water grid, these standalone toilets circumvent costly, water-andenergy-intensive municipal sewer lines and treatment facilities while consolidating nitrogen-, potassium-, and phosphate-rich wastes so they can be used as fertilizer in backyard or community gardens.
Power from Pee?
But what about all that stored pee? Glad you asked. It turns out that urine—the world’s most abundant waste—could become the fuel of the future. Ohio University researcher Gerardine Botte has developed a catalyst that can extract hydrogen fuel from urine. While it takes 1.23 volts to split two hydrogen atoms from water, it takes only 0.37 volts to strip four hydrogen atoms from a urea molecule. That’s twice as much hydrogen for one-third the effort. The Royal Society of Chemistry’s journal, Chemical Communications, confirms Botte’s discovery: “While water is an increasingly limited essential resource,” the journal notes, “there will never be a lack of urine.”
Existing nickel electrode technology can be easily scaled up to produce hydrogen from the liquid effluent of today’s sewage treatment plants. Tomorrow’s water-smart homeowners may need to adapt by adding one more container to the line-up for weekly curbside pickup—the urine bin.
Toilet to Tap
For decades, America’s orbiting astronauts have thrived by drinking their own urine, recycled endlessly through space shuttle filtration and purification systems. This water-saving solution hasn’t caught on down on earth. In 1994, the federal government established programs to convert wastewater into clean water for drinking, but the follow-through was lacking. The Bureau of Reclamation currently devotes less than 2% of its annual budget to water recycling programs. Fortunately, progress is happening at the state and municipal level.
In 1997, San Diego announced plans to have a “Toilet-to-Tap” system up and running by 2001. The experiment proved so successful that Orange County recently approved a $3.5 billion expansion of the program that is expected to meet 33% of the region’s water needs with a recycled product that is actually cleaner than regular tap water. While San Diego’s filtration system has successfully reduced contaminants to the same level as “untreated fresh water,” many potential customers still have qualms about sipping treated wastewater, even if it is a proven, space-age technology. However, if the drought persists, a refreshing drink may come at a price: we may have to swallow our pride first.
A Hotter, Drier Future?
As tough as the situation is today, it promises to get much worse in the very near future. In 2002, Geophysical Research Letters published a report by oceanographer John Church, whose studies of climate change from 1961 to 2008 concluded that trapped solar heat was pouring 125 trillion joules of heat energy into the ocean every second. This extraordinary thermal impact has been likened to the energy produced by the detonation of two Hiroshima-sized atomic bombs. By 2013, this troubling ocean warming had reportedly increased sixfold.
By absorbing 93% of all solar heat, the world’s oceans have masked our globalwarming problem by keeping the rate of atmospheric warming relatively low. But now a meteorological event known as the Pacific Decadal Oscillation may soon shift into a pattern that will reduce the ocean’s ability to store this excess heat. At that point, the stored heat will begin to pour into the atmosphere, leading to a stark rise in global surface temperatures. The UK Meteorological Office’s Hadley Center estimates there is an 85% likelihood that a massive blast of heat will sweep the planet in as little as five years—and could last for a decade.
The Political-Economic Challenge
Clearly, a single well-intentioned homeowner installing a water-saving faucet or low-flow toilet won’t have much of an effect on California’s overall water use—especially given the fact that 90% of the state’s “liquid gold” is consumed, not by residents, but by agriculture, industry, and the military.
Are we really prepared to face the trade-offs that may be needed to keep the taps flowing in drought-wracked California? For example, are we ready to double the amount of water available for California households by no longer watering all the municipal golf courses?
As Derrick Jensen (a self-styled “anti-civilization” activist and author of The Culture of Make Believe) argues, most of our environmental problems are products of our economic system, which means they can only be addressed by “shifting power away from corporations [and] stopping the growth economy that is destroying the planet.”
Clearly, we need more sustainable agriculture based on crops that require less water to grow (and fewer toxic chemicals to pollute our land, air, and water). We need to challenge powerful Big Ag lobbies (like the Westlands Water District) that profit from the profligate use of nature’s finite water resources. The days of growing almonds (a notoriously water-intensive crop) in the desert must end.
We need, as retired Congressmember George Miller recently observed, a “58-county approach” to replace the traditional, regional water-grab policies that pit cities against farmlands and industrial profit against environmental health. We need, as Naomi Klein (author of This Changes Everything) insists, “an economic and political transformation, one based on stronger communities, sustainable jobs, greater regulation, and a departure from this obsession with growth.”
I’ll drink to that.
Gar Smith is editor emeritus of Earth Island Journal, a former editor of Common Ground, and author of Nuclear Roulette.