Has a U.S. River Run Backwards Before?


The ongoing drought conditions wreaking havoc across large swaths of the country have driven the water in Lake Michigan an inch below its previous record low, and aren’t stopping. Last month, the U.S. Army Corps of Engineers announced that, if this continues and the lake water drops below the level of the Chicago River, the river could reverse course and begin flowing back towards its source. (Thankfully, there’s a series of locks separating the two, which will help prevent the less-than-clean river from flowing into the lake and the city’s source of drinking water.) Has an American river ever done an about-face like this before?

Right Back Where it Started From

Oh yeah. In fact, the Chicago has done it before. If the river does reverse course, it won’t be running backwards so much as running forwards again. 

When Europeans first settled in the Chicago area, the river drained into Lake Michigan, which was fine—except that settlers used the river to dump waste, and used the lake for drinking water. As the city grew, there were numerous outbreaks of typhoid and cholera because of contaminated drinking water, and something had to be done. 

In the late 1800s, the city decided to solve their problem with an ambitious engineering feat: They would reverse the flow of the river and send it away from the lake and towards the Mississippi River. The so-called “Chicago Diversion” worked: It not only diverted contaminated water away from the city’s drinking water, but also connected the Great Lakes and Mississippi River water systems and opened up the possibility of commercial travel and trade between them. 

It hasn't been just barges and haulers that could cross from one system to the other, though. Invasive Asian carp, introduced decades ago to southern fish farms as pond cleaners, have gradually made their way north, threatening native species and altering food webs as they go. With the fish nearing the Great Lakes, the idea of un-reversing (re-reversing?) the Chicago River has been kicked around, but now it looks like the river could take care of the problem itself. 

All Shook Up

The most famous of American Rivers, the mighty Mississippi, also might have gone backwards more than once. In 1811 and 1812, three earthquakes—the most powerful to ever hit the eastern U.S.—struck what was then a sparsely populated area of the Louisiana Territory. 

Eyewitness accounts from the quake read like Michael Bay scripts: The ground rippled and quivered; chasms opened up and swallowed livestock and wagons; sand and dirt exploded from the ground like volcanic eruptions and blotted out the sun; the Mississippi shook with such violence that the water ran backwards and boats were dragged upstream. 

One boatman, wanting to get away from the trees falling over on the river banks, put his boat out into the middle of the river and soon found, he claimed, that “the current changed, and the boat hurried up, for about the space of a minute, with the velocity of the swiftest horse,” fast enough that he had to hold on to his hat to keep it on his head. 

Gradually, the man said, the river returned to its normal course. Exactly how long that took is unclear, and various firsthand accounts have the river going backwards for anywhere from a few hours to a few days. Whether the river even reversed itself at all is questionable, and the United States Geological Survey says that ground uplifts and waves moving upstream may have just created the illusion that the water was moving backwards. 

What’s more certain is that the Mississippi reversed course for about 24 hours when Hurricane Isaac struck last year, and when Hurricane Katrina hit in 2005.

Do 'Close Door' Buttons in Elevators Actually Do Anything?

When you’re running late for work, one small comfort is finding an empty elevator waiting for you at your office building. You scurry inside, and since no one else is waiting to enter, you jab the 'close door' button. The doors comply, the elevator starts moving, and you breathe a sigh of relief.

This is a familiar scenario for many, but it’s also a big fat lie. That’s because most of the door-close buttons in U.S. elevators don’t actually work. In fact, they’re programmed that way.

But before you get ready to send off a strongly worded email to your office building’s elevator manufacturer, you may want to hear why this is the case. When the Americans With Disabilities Act was first passed in 1990, certain requirements for elevators were outlined, such as the installation of raised buttons, braille signs, and audible signals.

The act ensured that someone with a disability would have enough time to get inside, stipulating that elevator doors must remain fully open for at least three seconds and thereby preventing the button from cutting that time short. Some elevator manufacturers took it one step further by deactivating the button entirely.

Since the life span of an elevator is about 25 years and the Disabilities Act has been around for 28 years, it’s safe to assume that most of the elevators in operation today do not have a functioning 'close door' button, The New York Times reports. Only firefighters are able to close elevator doors manually through the use of a key.

It's important to note that there are exceptions to this rule, though. As the New York Daily News noted, New York City elevators are required by law to have working 'close door' buttons, even though some operate on a long delay (so long, in fact, that it calls the button's usefulness into question).

However, you’re in luck if you’re taking a lift (which, of course, is British for “elevator”). 'Close door' buttons are fully functional in most elevators in the UK, according to The Telegraph. A spokesman for the Lift and Escalator Industry Association told the newspaper that not all elevators have the button, but when they’re present, they do work. Again, the time it takes for the doors to shut after pressing the button varies from lift to lift.

While U.S. elevator manufacturers have a seemingly good reason for disabling the 'close door' button, some may question the point of propagating the myth and installing a button that serves no purpose in the first place. In response, some would argue that placebo buttons serve an important psychological function in society.

"Perceived control is very important," Harvard psychologist Ellen J. Langer told The New York Times. "It diminishes stress and promotes well-being."

That’s right: By believing that you’re in control of your fate—or at least how quickly you can make it up to the sixth floor—you’re better off. It doesn’t end with elevators, either. Buttons placed at city crosswalks are often disabled, and the thermostats in many office buildings are rigged so that the temperature can’t be altered (even if the numbers appear to change).

Some might swear up and down that elevator 'close door' buttons work, but this, too, could be your brain deceiving you. As author David McRaney wrote in an essay: “If you happen to find yourself pressing a nonfunctional close-door button, and later the doors close, you’ll probably never notice because a little spurt of happiness will cascade through your brain once you see what you believe is a response to your action. Your behavior was just reinforced. You will keep pressing the button in the future.”

According to The New Yorker, these buttons are designed to alleviate some of the subconscious anxiety that comes from stepping inside a tiny box that's hoisted up some 20 or 40 or 80 floors by a cable: “Elevator design is rooted in deception—to disguise not only the bare fact of the box hanging by ropes but also the tethering of tenants to a system over which they have no command."

So now you know: Next time you’re running late to work, take comfort in the fact that those few extra seconds you would’ve saved by pressing a functioning 'close door' button aren’t worth all that much in the long run.

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What’s the Difference Between Prison and Jail?

Many people use the terms jail and prison interchangeably, and while both terms refer to areas where people are held, there's a substantial difference between the two methods of incarceration. Where a person who is accused of a crime is held, and for how long, is a factor in determining the difference between the two—and whether a person is held in a jail or a prison is largely determined by the severity of the crime they have committed.

A jail (or, for our British friends, a gaol) refers to a small, temporary holding facility—run by local governments and supervised by county sheriff departments—that is designed to detain recently arrested people who have committed a minor offense or misdemeanor. A person can also be held in jail for an extended period of time if the sentence for their offense is less than a year. There are currently 3163 local jail facilities in the United States.

A jail is different from the similarly temporary “lockup”—sort of like “pre-jail”—which is located in local police departments and holds offenders unable to post bail, people arrested for public drunkenness who are kept until they are sober, or, most importantly, offenders waiting to be processed into the jail system.

A prison, on the other hand, is usually a large state- or federal-run facility meant to house people convicted of a serious crime or felony, and whose sentences for those crimes surpass 365 days. A prison could also be called a “penitentiary,” among other names.

To be put in a state prison, a person must be convicted of breaking a state law. To be put in a federal prison, a person must be convicted of breaking federal law. Basic amenities in a prison are more extensive than in a jail because, obviously, an inmate is likely to spend more than a year of his or her life confined inside a prison. As of 2012, there were 4575 operating prisons in the U.S.—the most in the world. The country with the second highest number of operating prisons is Russia, which has just 1029 facilities.

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