US Interstate 35 splits at Denton, heading southwest toward Fort Worth on one of its branches and southeast on the other toward Dallas. Denton is the northern apex of the so-called “golden triangle.” Development of farmland and prairie to suburbs, however, is much farther along to the southeast toward Dallas. For all intents and purposes, Denton (where I live) is the northernmost suburb of Dallas, now fully connected by development along I-35E, and people in Dallas use a lot of water. Per capita water use averages 250 gallons of water per day, much higher than in San Antonio (170 gallons per day) where climate is warmer and drier. Personal water use in Dallas is 100 gallons per day higher than the national average, and the average for the US doubles that of most other Western countries. By 2050 water use in Dallas is anticipated to rise, whereas it is expected to decrease in many other cities. Dallas is situated in the Trinity River drainage in an area where eighty-five percent of water use is municipal (meaning “used by citizens”), which means that “per capita use” is truly a matter of individual water consciousness (or lack thereof).
Assume, for the sake of argument (and based on the data presented above), that per capita water consciousness in the Greater Dallas Area is low, which translates into the generalization that “most people to do not pay attention to the quantities of water they use.” Should there be public concern? Yes, on nearly all accounts, water shortages are predicted in much of the American West in this century. Water conservation could make a huge impact on water use per day in this region because such a high proportion is municipal. Facing water shortages, why don’t people conserve? There are several reasons: 1) people think on short time scales, and do not anticipate long term shortages. Don’t believe me? Read about the Hohokam and other societies in the American Southwest (see also a general argument in Jared Diamond’s book Collapse, a readable popular book). 2) People are not aware of the cost of water (for excellent discussion see Mark Reisner’s Cadillac Desert, another readable popular book). 3) People are not aware of their water demand (see previous paragraph). 4) If people become aware, they do not know what steps to take to curb their demand, which is actually easy to fix.
Water is not a luxury; it is a necessity. Most animals (including humans) cannot live more than a day or two without drinking water. There are places in the world where there is not enough clean drinking water, and at the global scale, all water bodies are connected. Conservation has important local and global effects. Here are some water conservation measures that are easy to implement.
1) “Drink tap water; avoid drinking bottled water.” Sales of bottled water rely on a grand marketing ploy, that such water is more pure than tap water. There are several ugly facts however that pervade the bottled water marketing campaign, all of which are discussed in the documentary, Tapped. First, bottled water is at best tap water; the large corporations that bottle and sell water quietly purchase large tracts of land with groundwater resources, the same groundwater used by municipalities. Water is bottled and sold at the state level to avoid federal scrutiny. Bottled water is unregulated, tested only by the industry itself (without the same public reporting requirements that municipalities endure), and sold at an order of magnitude higher (or greater) price to consumers. In contrast, water from the tap is highly regulated, regularly tested for quality, and is cheap. There is no evidence that bottled water is cleaner than tap water; in fact all of the evidence is that regulated tap water is far more carefully screened for quality. Second, municipalities with minimal budgets now compete to sell drinking water against huge marketing machines. Municipalities bear all of the costs for recycling programs, and those conglomerates who bottle and sell the same water are happy to support the status quo. The result is a triple whammy! In addition to the unregulated tapping of local water sources and low funding for recycling programs, plastics from bottled water pollute hydrological systems from streams to oceans at alarmingly increasing rates, and those who sell bottled tap water pay nothing. Plastics from bottle manufacture and use are detrimental to human health, use petroleum products, and require distribution (= fuel consumption). Third, bottled water distributors play by a different set of rules for water consumption than do individuals relying on municipal water. There are a number of instances (reported in Tapped) in which water has been rationed to the general public during droughts, yet firms bottle from the same depleted sources at constant rates during such times. Use of bottled water is a waste of money and water, and in terms of quality it does not come close to tap water. Put your money back into your municipality to support regulated water treatment, recycling programs, freshwater and marine ecosystem health, and conservation.
2) “If it is yellow, let it mellow. If it is brown flush it down” (unattributed adage). Gross, right? Perhaps (disgust is culturally determined, by the way). However, urine is actually quite sanitary, such that some hunter-gatherers used it as a disinfectant. More important, if toilets are kept clean, it makes no difference if urine sits in the commode between uses. About a gallon of water is used to flush a few ounces of urine if one flushes each time; half of that water is saved just by flushing every other time! This may or may not be for you, but it does save water.
3) “Grow Bermuda grass instead of St. Augustine.” Bermuda is drought tolerant, requiring moderate amounts of water about once per week. Native buffalo grass varieties require even less water. Most lawns are in open areas that receive a lot of sunlight; in this part of the world such areas are virtual deserts. St. Augustine requires intensive watering to maintain the lush, green lawn that many people desire.
4) “Water the lawn and yard plants in the middle of the night.” Sunlight transfers heat energy to the surface of the planet during the daytime, and heat causes water to evaporate. Nighttime watering allows percolation into soil to become soil water available to plants with less evaporation prior to infiltration. We can take a lesson here from various desert plants, which uptake CO2 at nighttime because to open their stomata (to absorb CO2) during the daytime would lead to high rates of evaporation, which would wilt the plant! Water at night.
5) “Use rainwater capture.” Watering of yard plants can be offset by capture of rainwater via harvesting from gutters and downspouts. At my house, we have three 50 gallon rain barrels on downspouts, which conserves over 1000 gallons of water per year. There are now systems that collect hundreds of gallons of water from roofs that can be used for watering of plants.
6) “Xeriscape.” When planting a yard do a moderate amount of research and select plants that provide desirable characteristics (e.g., shade, fruits, flowers) but that grow well in the region. Some of these, once established, use very little water.
7) “Put in a water-conserving shower head.” Perhaps you like to take long showers. Water conservation shower heads increase pressure at the head, thus reducing the overall amount of water used. Showers using these heads may take some getting used to, but if you want to reduce use of water, this is a great way to conserve on a daily basis.
Finally, it is important to realize that water consciousness and conservation falls under the realm of a “process goal.” The water conservation idealist would suggest that lawns are biotic deserts and that the best practice would be to do away with lawns completely. However, the reality is that lawns are part of American culture; better water conservation can be achieved by selecting relatively heat/drought-tolerant grasses, by practicing wiser watering (e.g., nighttime watering), by adopting a host of other practices that conserve water, and by simply valuing water for what it is, a necessity.
Acknowledgements: Much of what I have learned about water is anecdotal and is based on my opinions. I have learned a lot about water issues from close colleagues of mine, especially Tom La Point.
References:
How to Make a Big Impact: Water. Earth911.com, May, 2009.
Tapped. http://www.tappedthemovie.com/
Texas Water Development Board Region C Water Plan 2002. http://www.regioncwater.org/Documents/index.cfm?Category=2011+Init+Prepared+Plan+%28IPP%29
The Pursuit of Ecotopia: Lessons from Indigenous and Traditional Societies for the Human Ecology of Our Modern World, by Eugene N. Anderson 2010 Praeger, Santa Barbara
Collapse: How Societies Choose to Fail or Succeed: Revised Edition by Jared Diamon 2011 Penguin Books, New York.
Cadillac Desert: The American West and Its Disappearing Water, Revised Edition, by Marc Reisner 1993 Penguin Books, New York.
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