Water is the building block of all life, our most sacred resource and what makes our little blue planet so special. Unfortunately, human activity over the past dozen generations has diminished our relationship with water at the same time as we have harnessed better control over it than ever before. We now hold the power to harvest, divert, and dam huge rivers that flow for thousands of miles, but also the power to pollute, overuse, and fight over water that feeds millions of mouths and billions of acres of bioactive terrain. Central to our sustained fight for creating a better world is determining what to do about water- how to get it, how to preserve it, how to respect it and its impact.
A month ago I visited Mexico City, which is the largest city in the Western Hemisphere and was founded on the ashes of the Mexica (and later Aztec) city-state of Tenochtitlan, which was surrounded by water- a great lake. The cruel fate of the Aztecs at the hands of Hernán Cortéz is well known, but what is not is that Mexico City, now built over the drained former lake and its surrounding basin, is sinking, due to the over-extraction of groundwater from the [former] lakebed’s clay base. In some places, sinking happens at a rate of 1.7 inches per month, totaling over 30 feet over the past century! During my visit, I was connected through water activist Roberto Cerda with Mexican Senator Raúl Paz Alonzo, who represents the State of Yucatán. The Senator was so gracious as to host me for a day, and we discussed water security in the Yucatán peninsula, the impact of humans on the Mesoamerican Barrier Reef, and his role as president of the Senate Commission on Hydrological Resources (analogous to being a committee chair in the U.S. Senate).
Prior to meeting with the senator, I researched the hydrology of the Yucatán peninsula and discovered that the water cycle there begins in the mountainous rainforests in the south and continues down towards the ocean in a series of underground rivers and lakes. Sometimes natural sinkholes occur on the peninsula, exposing the aquifer below, forming what are known as cenotes. These cenotes are a crucial part of indigenous peoples’ livelihoods, as they are often the only source of fresh water available. Entire cities have grown around cenotes, including the famed Chichen Itza, and many are known to be sacred sites. However, the underground rivers that feed the cenotes, as well as offshore reefs, are highly susceptible to being affected by human pollution. As the population of the region has grown and demand for agriculture and industry has increased, infrastructure for wastewater and agricultural runoff hasn't caught up, resulting in the contamination of the aquifer. This results in two specific problems: Increased nutrient concentrations in the groundwater (due to agricultural fertilizers) drain into the ocean, disturbing marine ecosystems; and general human-caused groundwater pollution in upriver zones results in contaminated and unusable water downstream, threatening both natural ecosystems and local communities who are dependent on the water for their livelihoods. A similar problem can be found in resort towns along the coast, as the inability to enforce anti-pollution regulations due to local-level corruption results in the destruction of coastal and marine ecosystems. The solutions to these problems are straightforward to identify but difficult to implement: Develop sustainable fresh- and wastewater (grey and sewage) infrastructure throughout the peninsula and root out and disincentivize corruption at local levels in major tourist hubs on the coast.
And yet, Mexico isn’t the only country with water struggles, and the allegory of Yucatán is just one of dozens across the globe warning us of the grave effects of water security issues. Australia’s rainfall is more variable than any other place in the world due to being driven by the random ENSO instead of regular seasonal patterns; as a result, water storage facilities, notably dams, need to be twice as large as the global average to last through unpredictably long droughts. In China, over-extraction of groundwater, over-damming of rivers, and pollution of rivers have drastically affected ecosystems, resulting in downstream droughts, increased flooding and erosion, over 25,000 square miles of surface sinking (including in major population centers), 60% of rivers are considered unsafe for drinking, and nearly 300 million people (mostly in rural areas) lack access to clean water. India, which is home to nearly 20% of the world’s human population, has seen its total per capita freshwater accessibility drop from over 4 acre-feet in 1950 to 1.1 acre-ft. today, and is on track to shrink to below 0.9 acre-ft. by 2050; 80% of India’s freshwater is severely polluted due to over 32 acre-ft of wastewater flowing into the country’s bodies of water per day, resulting in over half a billion people who lack access to clean water. The Arab Spring, particularly the Syrian Civil War, is widely (in large part) attributed to water scarcity due to a prolonged climate change-linked drought in the MENA region from 2007-2010; this in turn led to the rise of ISIS, who also used “water weaponization” by capturing the Mosul Dam in 2014. Overall, over 4 million climate refugees are attributed to the Syrian Civil War alone, and it is predicted that there could be over 150 million more by 2050.
Nearly every country on Earth has their own water security issues, and likewise nearly every country will be significantly impacted over the next century by a coming wave of climate refugees. Beyond just direct human-caused water crises such as groundwater over-extraction, wastewater pollution, and overuse of agricultural water resources, natural disasters such as floods, hurricanes, and droughts are occurring 5 times as often as half a century ago. Creating solutions to the water-related problems we encounter will be crucial to prevent the decay of the human species and degradation of the environment.