[This report was produced for "Earth Beat" of Radio Netherlands Worldwide as part of a look at "megacities".]
The Magdalena River in southern Mexico City
Home to over 21 million people, Mexico City is the largest urban area in the Western Hemisphere. While its smog is world famous, its haphazard expansion has led to another environmental issue; it’s water system can’t cope. We sent Earth Beat correspondent Shannon Young to the city to look into the issues behind its those water problems.
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Live stand up next to river: “I’m standing along a stretch of the Magdalena River that comes through Mexico City proper. And at this point, it is a grey/green/brown mass of relatively viscous liquid. And there’s a small cascade here. It consists of a concrete block with broken tree branches and lots of garbage. I see a bottle of bleach, a rusty can of spray paint, lots of shredded tatters of plastic bags, some broken styrofoam plates, pieces of clothes…and it’s all really stinky.” (fade under river tone)
The Rio Magdalena is the only river considered to have any life within the limits of Mexico City. It originates in a forested area in the mountains west of the city, but is a putrid mess by the time it reaches the city’s southern edge.
Nearly all of the other rivers that used to exist in the city have since become vehicles for transporting sewage out of the metropolitan area.
AMBI: pumped water gushing into the giant septic tank (bed under)
Some of that water comes through here – the Aculco pumping station. Here, veteran engineer Jorge Chang Castro points out the sewage that’s being pumped into a giant concrete pool under our feet. The plant mixes sewage and storm water together and pumps them towards the main tunnels out of the city.
All of the water expelled from the main drainage systems is untreated and is used by farmers downstream for irrigation.
[fade out pumping station ambi]
But Mexico City’s pumping stations operate with outdated equipment. The Aculco station is at least 40 years old. When the pumps seize up, Julio Cesar Cu Camara has to go below the surface to manually unblock the pumps.
CLIP Julio Cesar Cu Camara 1 (translated): “The most common problem is garbage. All of the city’s litter ends up here, in the drainage system and it obstructs the pumps, the metal grates, the hatches. It’s always been the city’s biggest problem – the amount of trash thrown into the drains.”
Cu Camara is one of only a handful of sewage divers in the world …and one of only 2 working in Mexico City. The divers work blind because there’s no visibility in the raw sewage.
CLIP Julio Cesar Cu Camara 2 (translated): “I think the worst thing to find is a human being, because we’ve found bodies of people and we don’t know who they are. But there are also other outrageous things. I’ve found everything from cigarette butts to bits of cars and trucks, big tires, furniture, fridges, microwaves. We find all of it in the sewers. You’ve got to ask yourself how it got there? But there it is – it’s crazy. We’ll be down there working and be like ‘let’s see what this is here’ and we’ll feel around think ‘hmm this feels like a tire, ok let’s get it out of there.’ Then there will be something else – a tree trunk. So we get it out. And then suddenly we’ll be like ‘here’s something strange - a fridge! Hey – there’s a fridge here!’ Well, we have to get it out. But how does it all get there? Nobody knows.”
Fade under sound… [END OF PACK]
Marnie Chesterton: That was a pack by Shannon Young in Mexico City. Shannon joins us now. Shannon – it sounds disgusting! I hope you had a bath after that.
Shannon Young: Yes…and I thought twice about where I was going to eat lunch.
MC: Oh, I’m so sorry we sent you there. Why are things so bad? Is this a city full of people putting fridges down the sewers or is this simply a question of not keeping up with infrastructure?
SY: Well, one if the main problems is that the water system there is not designed to separate the storm water from the sewage. So, that’s problem #1. They’re pumped together untreated out of the valley Mexico City is located in via an artificial opening into a river.
While the city pumps polluted water out of the valley, it also has to pump up from more than 1000 meters below the surface its potable water.
MC: That’s really deep!
SY: Yeah, more than a kilometer.
I spoke with Arsenio Gónzalez of the national university’s Program for City Studies, and he says the problem with water in Mexico City is historical. Originally the valley where Mexico City is located was home to a system of 5 lakes, but in 1607 Spanish colonizers created an artificial canyon to drain these lakes and send raw sewage out of the city. And this pumping of the groundwater from below the surface has caused the city to sink in some areas by 10 or more meters.
MC: But surely Shannon the water infrastructure’s has been adapted or improved since then…
SY: There were three major public works projects in the 20th century that created other – or expanded upon – existing artificial outlets for the city’s sewage. But plans to recharge the area’s aquifers were neglected. Gónzalez says they’re essentially bringing in clean water at ever higher costs, dirtying it, then pumping it out of the valley.
CLIP Arsenio Gonzalez (translated): “What we’re seeing is that modern-day Mexico City, which is a city of 20 million inhabitants, gets around 70 percent of its water from underground sources… All the storm water and sewage is expelled to another watershed. So the problem is that the city isn’t self-sufficient with the water it has in its own watershed.”
SY: Like I said earlier, storm water and sewage is combined in Mexico, which is unusual for a large city. Deputy director of Mexico City’s pumping stations, Jorge Chang Castro says it’s time for officials to invest in separating the two types of waste water.
CLIP Jorge Chang Castro (translated): “It’s been 70 years already and we’re still working with this same idea. It’s time to change it. The government needs to invest money to separate the water. A few neighborhoods here and there have started to separate their water, but it needs to be done on a larger scale. Why? Because we need to use the rain water to recharge the aquifers. Or hell, build a dam!”
SY: Chang Castro says another potential source of potable water is the Magdalena River and that it’s important to make sure that it
Trash in the Magdalena River
doesn’t get contaminated as it enters the city. But as you heard earlier, the restoration of this polluted section of the Magdalena River seems like a distant reality.
CLIP Arturo Rivas Montaño 1: “en mi infancia el agua era un poqito mas clara. Inclusive se veían las piedras qe estaban en el río, osea piedras peqeñitas y pasaba el agua. Si si habia piedras.” (SY translates.)
SY: That’s forty-nine year old Arturo Rivas Montaño. He grew up in the district of Coyoacán and says that when he was a kid, the water was clear enough to see the stones on the bottom.
CLIP Arturo Rivas Montaño 2: “Lo qe me comentan mis abuelos, que también ellos son de aquí nativos, qe antes, en sus tiempos de ellos iban a lavar la ropa, el agua era un poqito mas limpia. En aqel entonces ellos le nombraban el acueducto qe era la parte qe ellos iban alla a lavar su ropa. Entonces mis abuelos decían qe el agua era muy clara muy limpia y no había ninguna enfermedad. Ahora ya no.” (SY translates).
Rivas says his grandparents can recall times when people were able to wash their clothes in the river. The water was very clean and didn’t carry sicknesses. That’s not the case anymore.
MC: Right…yeah. Like you said at the beginning; rusty spray cans, plastic bags, concrete blocks, fridges. But even if this river is rescued, it sounds like Mexico City’s water issues are way bigger than a single river is going to solve…
SY: Yeah, you’re right. Another huge problem in Mexico City is the fact that the city is sinking. When they originally built these pumping plants more than 40 years ago, they were built on the outskirts of the city. Now those areas have become heavily populated. As the city sinks, there’s no longer this force of gravity to send the waste water to the pumping stations.
A couple of areas of the city have even experienced sewage floods – where it goes into the homes. And if the main tunnel that expels sewage from the city we to experience some major problems, a huge swath of Mexico City – from the airport into the downtown area – would flood with sewage
MC: Ummm – not good. I guess the question is will they opt for new and preventative ways – or continue with the 400 year old model of bringing it in, polluting it, and the spending energy on pumping it away again?
SY: Well, most people who work with water issues in Mexico City say that it’s also clear the city’s water problems require not only new ideas from engineers and city planners, but there also needs to be a political will to finance it and to really move these projects forward. There also need to be participation from the citizenry and the various sectors of this massive city’s population to make it work.
It requires a major change in the mindset of the general population and that’s not something that’s easy to achieve.