The Power of Water Pressure
When we turn our tap on and fill a glass of water, we’re benefiting from one aspect of water under pressure. It is easy to take this for granted, and it provides very little insight into the real power of water when put under pressure. High-pressure water occurs naturally in nature, found in everything from geysers to tsunamis. Likewise, mankind has found many ways to put water under pressure to work for many purposes.
A Sense of Urgency
Interestingly, the word pressure comes from the Latin word urgentia, which means to be under pressure. It is also where we get the word urgent, when we feel under pressure to get something done quickly. In reality, all of nature is subjected to various forms of pressure, and it can be creative or destructive.
We use pressure with water to power our fire hoses, clean dirty surfaces, and even to cut metal into various pieces and designs. In fact, one of the first inventions to start the Industrial Revolution was a steam engine, used to move a piston with pressurized steam. Along with the many thousands of different ways we put water to work today, tools like a snap-on pressure washer seem like a very sophisticated device compared to those early steam engines.
A cubic yard of water weighs just under 1,700 pounds, as much as a small electric car. When that water accelerates, it creates a force much like being hit by a moving car. If the force is the wave from a tsunami, the speed of the car-like water can exceed 40 miles per hour. It is easy to understand, then that being hit by tens of thousands of cubic yards of water traveling at that speed has the destructive power of an equal number of vehicles crashing ashore.
In the tsunami that hit Japan in 2011, scientists estimate billions of cubic yards (all weighing 1,700 pounds) hit the coast, causing immense damage. Beyond tsunamis, however, pressure from even gently flowing water reshapes our landscapes and grinds down mighty boulders to small stones.
Modern structures, such as dams and bridges, have to be built with the power of water taken into consideration. For example, the base of the Hoover Dam has to withstand pressures of more than 45,000 pounds per square foot. To do this, the engineers on the dam had to use more than three million cubic yards of reinforced concrete.
Good or bad, water pressure is a force of nature to be reckoned with.