17 February 2017, New York Times, Mexico City, Parched and Sinking, Faces a Water Crisis. Climate change is threatening to push a crowded capital toward a breaking point. MEXICO CITY — On bad days, you can smell the stench from a mile away, drifting over a nowhere sprawl of highways and office parks. When the Grand Canal was completed, at the end of the 1800s, it was Mexico City’s Brooklyn Bridge, a major feat of engineering and a symbol of civic pride: 29 miles long, with the ability to move tens of thousands of gallons of wastewater per second. It promised to solve the flooding and sewage problems that had plagued the city for centuries. Only it didn’t, pretty much from the start. The canal was based on gravity. And Mexico City, a mile and a half above sea level, was sinking, collapsing in on itself. It still is, faster and faster, and the canal is just one victim of what has become a vicious cycle. Always short of water, Mexico City keeps drilling deeper for more, weakening the ancient clay lake beds on which the Aztecs first built much of the city, causing it to crumble even further. As Arnoldo Kramer, Mexico City’s chief resilience officer, put it: “Climate change has become the biggest long-term threat to this city’s future. And that’s because it is linked to water, health, air pollution, traffic disruption from floods, housing vulnerability to landslides — which means we can’t begin to address any of the city’s real problems without facing the climate issue.” Read More here
Tag Archives: water
14 February 2017, Think Progress, Sinking from drought, California is now also flooding. After weeks of rain, Northern California’s surface water systems have been pushed to the breaking point, even while the effects of a five-year drought continue to threaten the state’s long-term groundwater supplies. More than 180,000 people were evacuated Sunday afternoon after spillways for the Oroville Dam in Northern California showed signs of possible collapse. The potential flooding comes as California begins to emerge from its historic, drought. But despite the overabundance of water on the surface, drought conditions underground have likely had a permanent impact on the state. Even under the best conditions, it could take half a century for underground reservoirs to refill. Recent analysis from the California Institute of Technology shows that drought — combined with water use — has caused parts of California to sink, perhaps permanently. Some places show up to two feet of subsidence over the past two years. That’s because as surface water from rain and snowmelt has decreased, farmers have been using more groundwater from reservoirs. “Subsidence caused by groundwater pumping in the Central Valley has been a problem for decades,” write the authors of a new study, which uses NASA data to track California’s sinking. Pumping groundwater reduces the support below-ground aquifers give to the surface, causing it to sink. In recent years, that process has been sped up, as California’s drought has reduced the surface water available to farmers. While surface water can come in the form of rain, or snowmelt, groundwater sits in aquifers and is the result of a slow build up of water below ground. Read More here
21 December 2016, The Conversation, Why we can get over the ‘yuck factor’ when it comes to recycled water. In light of climate change and a growing population, water authorities around the world are looking at the treatment of recycled water to achieve water security and sustainability. Recent authors on The Conversation have raised the possibility of expanding the use of water recycling in Australia, noting the potential benefits for domestic, agricultural and industrial water supply. Some contributors have noted that the major roadblocks to water recycling, in places where it could be beneficial, are not technical issues, but public reluctance to use recycled water. Emotional Responses In the past, our aversion to recycled water has been explained by the “yuck factor”. Some people have an emotional response of disgust to using recycled water, even when they know it has been highly treated and is safe. There are large individual differences in the strength and type of different people’s disgust responses. Psychologists have tried to understand why our thought processes can lead some people to think of recycled water as unclean. One explanation is contagion thinking, the idea that once water has been defiled it will always remain unclean, regardless of treatment, at least according to the mental models that underlie our emotional responses. What such approaches often neglect is that cognition does not occur in a cultural vacuum, but is affected by the associations and stigmas of society. It is important to note that these emotional responses are often in conflict with our rational thinking. Some theorists, such as Nobel laureate Daniel Kahneman, have argued that we make judgements using two contrasting systems. One of these systems is slow and operates according to a formal risk calculus. The other is fast, based on positive or negative emotional responses. Because of this, how we feel about someone or something (positively or negatively) is often as important as what they are being judged on. In other words, the fact that a person understands that a highly treated sample of recycled water is safe to drink may not be enough to stop the emotional response, as we often tend to think intuitively, drawing on our social and cultural values. The most important question, however, is whether the emotional responses some people have to recycled water can be changed. And what role do stigmas associated with cultural norms play in shaping these? Read More here
26 November 2016, Climate News Network, Bolivian water crisis as glaciers vanish. Bolivia has declared a state of emergency as climate impacts shrink glaciers and leave cities without water. The government of Bolivia, a landlocked country in the heart of South America, has been forced to declare a state of emergency as it faces its worst drought for at least 25 years. Much of the water supply to La Paz, the highest capital city in the world, and the neighbouring El Alto, Bolivia’s second largest city, comes from the glaciers in the surrounding Andean mountains. But the glaciers are now shrinking rapidly, illustrating how climate change is already affecting one of the poorest countries in Latin America. The three main dams that supply La Paz and El Alto are no longer fed by runoff from glaciers and have almost run dry. Water rationing has been introduced in La Paz, and the poor of El Alto − where many are not yet even connected to the mains water supply − have staged protests. The armed forces are being brought in to distribute water to the cities, emergency wells are being drilled, and schools will have to close two weeks ahead of the summer break President Evo Morales sacked the head of the water company for not warning him earlier of the dangerous situation, but the changes produced by global warming have been evident for some time. Read More here