The New York Times recently published an opinion piece on the cost of big dam projects.
Large Dams Just Aren’t Worth the Cost by Jacques Leslie, August 22, 2014
Beautiful photograph with it, lots of water spilling from the dam.
Have a read, and you may notice that the word water is not mentioned in the text once!
These are breathers, or ventilation chimneys — sometimes even called “burpers” — that are installed at regular intervals along the approximately 30 kilometer aqueduct built around the turn of the last century to bring potable water from Xochimilco to Mexico City (for more about this, click on Our Water Project in the nav bar). These aren’t unique to the Xochimilco network, of course. New Yorkers also will find them along the Croton Aqueduct, for example. They allow air to be released from the subterranean pipes carrying water from its source (springs, reservoirs, etc.) to water distribution sites and ultimately to its users. They create a kind of water-engineering landscape.
They are pretty weird looking though. The jaunty fellow in the black and white photo below looks like he’s standing next to some forlorn column from a ruined temple. (This photo is from a 1910 publication on Xochimilco water network.) Imagine bumping into one today in the middle of the lovely Condesa neighborhood in Mexico City. How many people do you think even know what that is? The little sign on it just tells you not to mark it up, but not what it is! Interesting that these commemorate a water network that didn’t survive for very long…
Put this on your to do list: Look around your own neighborhood for signs of the history of the water you drink.