Times of social stress, hardship, and uncertainty spur interest in all kinds of divination and prophecy. The public goes to see psychics and fortunetellers more often in times of economic depression than prosperity, times of loss rather than love. It’s human nature, and magical thinking in its various forms—including superstition and conspiracies—helps people cope with daily stresses. People want to be reassured that good things are just around the corner, that fortunes will improve and whirlwind romances with proverbial tall handsome strangers are in the cards. People want an edge against random chance.

This was true during the pandemic, but there are other stresses—environmental ones such as climate change, widespread fires, and an enduring drought that’s kept much of the Southwestern United States parched for years. It’s no surprise that people are getting more desperate to find water.

The New York Times recently reported a jump in interest in, and hiring of, dowsers (or “water witches”), such as Rob Thompson, who “claims that he can locate streams of water in the fractures in the earth’s bedrock, using two L-shaped rods that together resemble an old-fashioned television antenna. Amid California’s extreme drought, just a two-hour drive north of the nation’s technology capital of Silicon Valley, the water-seeking services of a man relying on two three-foot rods and a hunch are in demand. ‘This is my busiest I think I’ve ever been in my life,’ said Mr. Thompson, a third-generation water hunter with silvering hair and the lumbering gait of a bear… His busy schedule is a sign of the desperation of ranchers, vineyard owners and land managers as California reels from a crippling drought that has depleted aquifers, shrunken crops and forced some farmers to sell off their water rights.”

If you’ve ever heard the phrase “They wouldn’t do it if it didn’t work,” dowsing is a perfect rebuttal. People through the centuries have revered and perpetuated practices despite the fact that they simply do not work. Dowsing is a textbook example of this. Part of the reason for dowsing’s longevity is its versatility in the paranormal world. If we conceive of the paranormal as a tasty (but ultimately nourishment-free) meal, dowsing is a sort of all-purpose side dish. It can stand alone as a New Age endeavor when searching for water or missing jewelry, or it goes equally well with a variety of pseudoscientific main dishes, including crop circles and fortune-telling. Dowsing is said to find anything and everything, including missing persons, buried pipes, oil deposits, and even archaeological ruins (see “Dowsing and Archaeology: Is There Something Underneath?,” in Skeptical Inquirer, March/April 1999).

I most often encounter dowsers during ghost investigations. Many amateur ghost hunters use dowsing rods to search for ghosts, believing that ghosts can be detected by (or communicate through) dowsing rods. In 2007, I demonstrated dowsing for the National Geographic Channel’s Is It Real? TV series on “Ghost Ships” in response to a woman who used dowsing rods on ghost hunts.

The dowsing with which most people are familiar is water dowsing (also known as water witching or rhabdomancy), in which a person holds a Y-shaped branch or two L-shaped wire rods and walks around until he or she feels a pull on the branch or the wire rods cross, which allegedly indicates that there is water below. Often a pendulum is used, sometimes held over a map.

According to proponents, dowsing has a robust history, and its success has been known for centuries. For example, in her book Divining the Future: Prognostication From Astrology to Zoomancy, Eva Shaw writes, “In 1556, De Re Metallica, a book on metallurgy and mining written by George [sic] Agricola, discussed dowsing as an acceptable method of locating rich mineral sources.” This widely cited reference is a rather transparent example of a logical fallacy called the appeal to tradition (“It must work because people have done it for centuries”).

However it seems that the dowsing advocates didn’t actually read the book because it says exactly the opposite: Instead of endorsing dowsing, Agricola states that those seeking minerals “should not make use of an enchanted twig, because if he is prudent and skilled in the natural signs, he understands that a forked stick is of no use to him.” So even 465 years ago, dowsing was recognized as worthless.

How Dowsing ‘Works’

If you assume that dowsing works—and that is of course a huge unproven assumption— how does it work? The proposed mechanisms are as varied as the dowsers themselves. One source states that “Dowsing is possible … through the strong psychic energy radiated by the object and picked up by the [dowser]”; another confidently states that “dowsing is not weird or spooky … it is as natural as memory. In fact, some scientists believe it may well be one of memory’s forms … a vestigial memory of a survival method of searching, using senses other than the five obvious ones.” The Amazing Randi in his Encyclopedia of Claims, Frauds, and Hoaxes of the Occult and Supernatural, notes that dowsers often cannot agree on even the basics of their profession: “Some instructions tell learners never to try dowsing with rubber footwear, while others insist that it helps immeasurably. Some practitioners say that when rods cross, that specifically indicates water; others say that water makes the rods diverge to 180 degrees.”

I don’t believe dowsing per se is fraudulent—that is, for the most part it’s not a scam, hoax, or intentional deception. Instead it’s a form of self-deception that often convinces others. There’s no intent to deceive, it’s more of a mistake or misunderstanding. I’ve met many dowsers over the years and without exception they have been credible, down-to-earth people. They seem sincere because they are sincere: they really believe they have this power, and have convinced themselves over and over with their results. In this way they often convince other people—especially those who haven’t researched skeptical or science-based explanations. Sometimes the dowsing rods cross or the forked twig does seem to dip—but that doesn’t necessarily mean there’s water below. The cause is what in psychology is known as the ideomotor effect: unconscious movements that make the dowser think that some other mysterious force is at play. If the dowsing devices were moving independently of the dowser then this should be easily demonstrated, but it doesn’t happen.

Testing Dowsing

Dowsers have been subjected to many tests over the years and have performed no better than chance under controlled conditions. There are various ways to scientifically test dowsing abilities. I have done it several times myself, and read studies done by others. The easiest is to get 20 identical 5-gallon opaque plastic buckets and (with the dowser out of sight or at another location) place a sealed gallon jug of water under one of the buckets (being careful of course not to leave any traces that might reveal where it is). The buckets should be placed 2-3 meters apart (or at whatever interval the dowser claims they can discriminate water from non-water). Have the dowser come out to the field or lot and find the water. You can do a similar experiment hiding valuables on sandy beaches in grids as well. For more on this see CFI’s Jim Underdown of the Independent Investigations Group demonstrating dowsing testing for NBC News.

The problem is that dowsers fail to demonstrate their ability in scientifically controlled experiments and tests. It also depends on what you’re looking for and where. In fact it can be difficult to disprove a dowser’s claim for the same reason: if they claim water will be found in a spot at a certain depth, they can always insist that the water is there—just that they were a bit off on the depth: It’s 50 meters, not 20 meters like they thought. In order to prove or disprove that, of course, you’d need to dig another 30 meters (possibly a difficult and expensive proposition).

And if they find water, does that mean that dowsing works? Not necessarily. In most places on Earth there’s water somewhere below the surface—maybe a few inches, maybe a few meters or more. So any dowser who says “If you dig here you’ll find water” is statistically very likely to be correct—and would be just as correct if he or she chose a spot 10 meters away in any direction, or 10 miles away. There’s also the issue of what psychologists call “confirmation bias,” also known as “remembering the hits and forgetting the misses.” People generally tend to better remember their successes than their failures, or they rationalize away their failures (“I was having an off day,” or “The sun was too hot,” etc.). Unless dowsers keep careful track of all their claims—both correct and wrong— it can be easy to misremember their success rate.

Of course when dowsers are wrong they simply point out that no one is 100% accurate all the time—doctors, mechanics, scientists, and others make mistakes, and this is of course true. But the problem with that comparison is that doctors and mechanics can reliably prove their skills most of the time; this is not true with dowsers, and in fact there is no known scientific mechanism by which a forked branch, pendulum, or two L-shaped rods could possibly “detect” water. Keep in mind that dowsers claim to be able to find a great many “hidden” objects, including missing keys, water, oil, gold, and even ghosts! This raises the interesting question of how dowsers could know what the rods are reacting to: Is it a vein of gold 20 meters below the earth, a reservoir of water 100 meters below the earth, oil shale 200 meters down, or the dead spirit of someone who died at that spot in 1973? There’s no way to know. British Petroleum and other multinational oil companies spend billions of dollars trying to locate offshore oil fields through expensive, difficult, and time-consuming sampling, computer models, and so on.

In fact in September 2015 the Royal Dutch Shell Corporation abandoned its drilling in the Alaskan waters after spending $7 billion searching fruitlessly for oil. Why would they do that if all they need is to have a dowser on hand to point them directly where to drill? Any dowser who could reliably and successfully do what they claim could easily become a multi-millionaire consulting agent. Why doesn’t it happen?

There is no science behind dowsing, and though the main harm is wasted time and effort, it can also cost lives: in 2010, modified dowsing-rod devices claimed to detect bombs were sold by a man named James McCormick to the Iraqi military. As Slate noted, “McCormick’s company was selling these fraudulent magic wands at great expense to the Iraqi government, which spent $16,500 to $60,000 each for these things, devices which might as well have been crayon boxes full of rocks. They were useless. Or, as it turns out, far worse than useless. The Iraqis were using them at military checkpoints. On Oct. 25, 2009, terrorists carrying two tons of explosives got right past the magic bomb sniffer and detonated their cargo, killing 155 people. Two months later, it happened again, with 127 people killed. Not long after, McCormick was arrested under suspicion of fraud.” In April 2013 McCormick was convicted.

The consequences of water dowsing is less dire but no less real: wasted time and effort. Still, as long as there are desperate people who need increasingly scarce resources, water witches will not be far behind.