Posted on 09/16/2021 5:46:36 PM PDT by Roman_War_Criminal
Mexico City’s water is quite literally disappearing. I have no doubt that in 2022 there will be a crisis, the reservoirs are completely depleted.
What is happening in Mexico City? The ancient Aztecs originally engineered the origins of Mexico City on top of Lake Texcoco and left the surrounding natural freshwater lakes intact for use. However, as the city grew the lakes were drained to make way for infrastructure, homes, and a growing population.
With expansion came an increasingly dire water security dilemma. Much of the city’s water supply comes from an underground aquifer that is being drained at an irreplaceable rate. As the aquifer is drained, Mexico City is sinking downwards rapidly at twenty inches per year.
Despite heavy flooding and rainfall, the city is facing a water shortage. In fact, more than 20 million residents don’t have enough water to drink for nearly half the year.
One in five people have access to only a few hours of running water from their taps a week and 20% have running water for part of the day. Counting on clean water is far from reliable for many.
Current projections estimate that global demand for fresh water will exceed supply by 40% in 2030. Mexico City, one of the largest cities in the world, has a population of nearly 22 million and is growing steadily with population growth expected to hit 30 million by 2030.
Mexico City is one of 11 cities predicted to reach what is called Day Zero, or the day when the water runs dry. This is nothing short of a crisis. “Each drop of water that passes through the Mexican capital tells a heroic, tragic, unfinished story of urban growth and human development.”
Why is Mexico City in a water crisis? There are a few reasons why a city on top of an aquifer and with a very heavy rainy season struggles to provide potable water for its residents. Specifically, the challenges to water security are widespread and difficult for urban designers, environmentalists, and politicians alike.
A lack of sanitary wastewater treatment across the city hinders water collection and poses a huge challenge to keeping existing water clean for use.
Additionally, Mexico City’s pipes are old and leaking. According to the University of Pittsburgh, Mexico City loses 1,000 liters of water per second because of an outdated water system that is being crushed by the falling city and punctuated by thousands of small leaks.
Finally, rainwater collection exists, but no city-wide system is in place. When it rains, water often mixes with sewage and cannot be used.
Why is the city sinking? Mexico City ended all groundwater drilling in the city central in the 1950s yet water is pumped up from below in the surrounding areas and GPS data has found the city is continuing to drop.
As water extraction has chased groundwater deeper and deeper underground, the clay lake bed is now completely dry and the tightly packed mineral soil is causing irreversible compaction. This phenomenon, called subsistence, does not have a quick fix.
Additionally, water from rain storms cannot permeate the concrete-covered city and refill the aquifer. A 2021 study made the claim that there is no hope for significant elevation and storage capacity recovery. Much of the water must be pumped to the city using hydro engineering from reservoirs thousands of kilometers away.
Drought is a threat multiplier Mexico continues to experience one of the most widespread droughts in decades. Unusually low rainfall has already reduced access to water in the capital. The reservoirs in Cutzamala outside the city provide a quarter of the city’s water but in 2020 the reservoirs were nearly 18 percentage points below normal levels. As precious reservoir levels plummet, the city authorities have reduced the flow from the reservoirs, which has been affecting tap water access. Some residents are relying on water delivery trucks and even donkeys.
This occurrence is predicted to repeat. Researchers have estimated the availability of natural water for the city could decrease by up to 17% by 2050 as temperatures rise.
“More heat and drought mean more evaporation and yet more demand for water, adding pressure to tap distant reservoirs at staggering costs or further drain underground aquifers and hasten the city’s collapse,” writes Michael Kimmelman for the New York Times.
What is Mexico doing to stop its water crisis? Mexico recognizes the pressing issue of water facing their biggest city. Mexico City initiated the Green Plan project, which will run until 2022 with goals such as reducing groundwater losses and repairing water infrastructure among others.
Former president Enrique Peña Nieto signed a series of presidential decrees in 2018 to create water reserves in nearly 300 river basins throughout the country. And $7.4 billion has been dedicated to mitigating the water crisis by Mexico City Mayor Claudia Sheinbaum Pardo in 2019.
It’s a paradox. It’s a catastrophe. Right now Mexico City is sinking and its infrastructure is literally breaking. And on the other hand there is no way for the water to filter into the aquifer naturally. And you can imagine how expensive it is to change the entire piping system.
There is no easy solution to Mexico City’s water crisis, but perhaps it lies in communal, accessible spaces above ground instead of below.
Vegas is the textook example of water recycling. They are allocated 300,000 acre feet per year they use 400,000 total but returns 230,000 acre feet per year via the las Vegas wash due to recycling every drop of water that hits a drain in the las Vegas basin. They use less than their 300,000 net and bank every year water in lake mead for a dry day. California is allocated 7 million acre feet and uses nearly 5 million acre feet per year to water grass in the desert to send hay to places like Saudi Arabia. So who is the wasteful ones?
Las Vegas just completed their 3rd intake it’s at 860 feet MSL the dead pool level for lake mead is 895 MSL where not a single drop can be sent down river. From 895 to 860 is 4.2 million acre feet that Vegas has access too when Hoover dam can’t sent any water down stream Vegas that’s 12 years of water at full Vegas consumption levels. With no inflow of water from the upper basin states a impossibility.
42 million visitors per year and less than 3% of total water use that’s epic level conservation.
https://m.lasvegassun.com/news/2018/may/10/the-strip-might-use-less-water-than-you-think/
https://truthout.org/articles/why-las-vegas-is-at-the-heart-of-western-statess-water-conundrums/?amp
https://m.lasvegassun.com/news/2014/aug/24/how-our-water-goes-toilet-tap/
https://lynceans.org/all-posts/las-vegas-made-a-good-bet-on-the-third-straw/
https://www.theguardian.com/us-news/2019/mar/25/california-water-drought-scarce-saudi-arabia
reverse osmosis is usually set at a 50 % recovery rate so permeate brine is usually at twice the incoming seawater ppt count. For normal seawater that’s 70,000ppt in brine. The Israeli method is to inject that water under considerable pressure and force through a series of pitfall nozzles miles off shore where due to its velocity and force is instantly mixed with 10 times or more ambient seawater lowering the salinity to less than 40,000 ppt a few meters from the nozzles it’s a non issue from that point forward as the 40,000 ppt mixes down to ambient in a few hundred more meters no density difference can form with salinity that close to ambient.
Now that sounds like it wouldn’t harm the marine life. The pressure from the water would probably prevent them from getting too close to the high pressure nozzles.
Even if they did get close they would just be pushed away by the current the exposure to the slightly higher salinity is transient. They fish for a good portion of the protein in that country they love and cherish the Med.
The Israelis are the world leaders in desal they have it down to 54 cents per cubic meter. That’s cheaper than the water from the tap in DFW by half on a 1000 freedom units to the equal amount in European units. They also lead the world in water recycling 80+% of their water is reclaimed and used for agriculture and other nonpotable use once it leaves the sewerage system which is tertiary treated to be sterile and nearly pure enough to drink directly.
The current population is exceeding the carrying capacity of the earth. The idea of having 2 children after age 30 is to gradually decrease the population by several billion so that it once more is matched to the carrying capacity of the land and seas. Then new ideas could be encouraged to maintain the population at a healthier level. The population would not be dying off, it would merely be gradually reduced to a healthier level, and no one would be deprived of having 2 children. Also, no more child marriage, or people having children before they have grown up to be responsible parents. I have spoken with more than one young man who at around age 26 to 28 has asked me, “Do you know any nice girls, you know, the kind you might marry?” That is a healthy age for a young man to think about marriage, wild oats have been sown, and maturity and responsibility is being reached.
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