Head guard Mike White stands beside one of the impellers.
Watching kids bobbing up and down at the Desert Wave pool raises an important question: how does the wave pool make its waves?
I needed an answer so I talked with lifeguard Michael Rigby and head guard Mike White, who explained it all to me. To my surprise, I already knew. I found out that I had discovered the basics of the wave pool 57 years ago, at 66 Tracy St. in Buffalo, N.Y., in my bathtub.
I was sitting in the tub, bored to death, looking at a little boat that was floating at the foot end of the tub like a dead goldfish. Making one of those random motions that kids do, I gave the tub water a push from the bottom toward the boat. The boat rose up, then came down and a second later the water came up a little bit around my chest and went down.
I did it again. Then I discovered that if I have a little push every time the water was high at my chest and heading down, I could make bigger waves. And bigger. It was not boring anymore. Colossal waves, oceanic waves, surrounded me.
Then - and you knew this was coming - one of the waves breached the end of the tub and splattered on the floor. My mother barged in a second or two later and screamed, "What's going on in here?" In all honesty, I told her, "Nothing."
The technology has improved since my unpatented discovery, but the principle is the same. Here, according to Rigby and White, is how it works.
At the deep end of the pool is an elevated deck that runs the entire width of the pool. Behind the deck is a building that houses the machinery we'll talk about in a minute.
Underneath the deck is a series of vaults that are partly filled with water. The water in the vaults is exactly as deep as the water in the pool. This is because water from the pool connects to water in the vaults through the grated openings you can see at the bottom of the wall, and the water on both sides of the wall seeks the same level.
Above the water in the vaults is air. Vents lead into the tops of the air chambers. Outside the chambers, in the basement of the building, gigantic blow-dryers are connected to the vents. Technically, they are called impellers, but hurricane-force blow-dryers is what they are.
To get things going, a lifeguard pushes a few buttons on a control panel on the top floor of the building. Then a series of rhythmic things begins to happen. High pressure pistons close little doors on the vents forming an air-tight seal. The impellers then send a whoomph of air into the top of the vaults.
The pressurized air forces some of the water down and out through the grates at the bottom and into the pool. (This is what my five-year-old hands were doing in the tub.) The water itself doesn't move very far, but the pressure wave goes all the way to the shallow end. Then the little doors on the vents open, releasing the pressure. Water comes back in. This goes on over and over, with each pulse amplifying the wave action until the whole pool is in motion, with white capped waves forming at the shallow end.
If you are a careful observer, you will notice that the pattern of waves in the pool is not the same all the time. This is by design. By forcing water out only through the center vaults, guards can create standard-issue waves, rolling one after another. When the vaults on the sides come into action, waves will reflect off the sides of the pool and converge in the middle, forming a diamond pattern of great mounds of water.
You can hear the whole process from hundreds of yards away, but inside the building it is louder than a rock concert. Nobody goes in there without ear protection.