2014 was the warmest year in recorded history and in some places, the driest. There are three major types of droughts—meteorological, hydrological, and agricultural—each with its own complex set of causes. Climate change plays a significant role in drought, through increased temperatures and disruptions to the hydrological cycle, but solely blaming climate change obscures the more tangible problem of water abuse and can become, according to activist Maude Barlow, “a catch-all for some governments to do nothing.” Unsustainable urban development and the productive processes that support it are contributing to and exacerbating the current droughts in the Southwestern United States, China’s Northern Plains, and Colombia’s Caribbean coast.
«Drought and Urban Development» is a three-part series that analyzes these three regions as case studies, focusing on one causal factor in each: residential sprawl, agriculture, and coal mining, respectively. In each, short-term profit-driven practices have caused the depletion and contamination of surface and groundwater. Unfortunately, the proposed solutions in each case are similarly myopic.
Part I: The U.S. Southwest
The Southwestern United States (here considered to include Arizona, New Mexico, Nevada, Utah, and southern California) has experienced the highest rate of population growth in the country over the past fifty years. The region’s population currently stands around 36 million, and Arizona—the most extreme example—saw its population increase from 756,000 in 1950 to 6.5 million in 2012 (US Census). It is also the driest part of the U.S.; Nevada and Utah respectively receive 23 and 33 centimeters of rainfall each year. The Southwest is currently in the midst of a devastating three-year drought that many predict will last much longer. A recent study predicted with 80% certainty that the drought will last a decade with a 5 to 10% chance that it will last half a century.
That this population explosion has occurred in a desert is only part of the problem. The other is sprawl, the dominant mode of residential development in the Southwest. Sprawl is characterized by low-density development, large lots, and the geographic separation of residential, commercial, recreational and work activities, all of which implicate car use and related infrastructures. Low density and large lot size are highly correlated to increased water consumption, principally due to higher outdoor water use and lawn watering. Water-wasteful recreational facilities like golf courses and water parks also abound in the Southwest. Notably, domestic water withdrawal in the region increased 410% between 1950 and 2000. Recognizing these practices as unsustainable, some local governments and businesses have begun to shift development patterns and punish water inefficiencies. California’s governor has outlawed a number of wasteful practices and Las Vegas’ water authority pays residents to replace their lawns with rocks and drought-tolerant plants. However, suburbanism’s cultural pull remains strong: Glendora, an affluent city outside of Los Angeles, threatened a fine of up to $500 and criminal action against a couple for not watering their lawn and keeping it green.
To support these water-intensive practices and facilities, states have dammed and irrigated the Colorado River, the region’s main artery, leading to declining water levels and flow. The decline of surface water has led farms and municipalities in the Southwest to mine for groundwater, draining 53 million acre-feet of the Colorado’s aquifers over the past 9 years. Private well-drilling companies in California have made small fortunes during the drought as farmers pay to dig deeper and deeper for groundwater. Worldwide, humans are withdrawing from aquifers faster than they can be replenished, extracting around 300 billion gallons daily. The Southwest is a particularly egregious case; groundwater extraction increased 62% between 1950 and 2000 in the region, and 324% in Nevada specifically. Digging for groundwater postpones the bigger problem of unsustainable (sub)urban water usage, somewhat like mining for tar sands rather than reducing oil dependence. Worse yet, there is no estimate currently of how much groundwater exists in the world so there is no telling how long this problem is being postponed.
The Southwest needs a sustainable long-term solution to its water problems and therefore must abandon its paradigm of low-density water-intensive residential development. Since the 1970s, Tucson, Arizona has been a model for such transformation in the region, with denser, mixed-use development, pedestrian-friendly infrastructures, water recycling, and the use of native plants. The local government has also invested in outreach and education campaigns and created incentives to reduce water use. Other municipalities in the region should follow Tucson’s lead and design around their environment, rather than squeeze every last drop out of the Colorado River to build white picket fences in the desert.
Next week: Can China’s massive river diversion project solve its water crisis?
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