Raindrops

The home sits at the bottom of a steep, two-to-one slope in Encino, Calif. When our Garden Artisan, Scott Cohen, arrived on-site, three retaining walls were rising up the slope – all made from braced railroad ties – to protect the home below from potential disaster. It was a late 1950s/early ’60s tract house, well maintained but in a tired style, and the man of the house said he didn’t even like the home and he might be inclined to cut and run.
The swimming pool and its surrounding structures replaced all three of the ugly retaining walls and enabled them to plant and beautify the slope. The backside of the wall was waterproofed with a hydrostatic-relief system in place and included a new, thoughtfully engineered drainage system that would collect all water from behind the wall and allow it to flow safely around the pool, deck and house on its way to the street. As for the pool and spa, they formed what Scott would call a nice little composition, with beautiful materials inside and out and a whole new look that transformed the backyard from “disaster in the making” to “gem set in a dramatic space.”
The pool is long enough for a bit of short-course lap swimming, while the spa is actually oversized and will hold a good number of family members or party guests. There’s a nice shallow lounging area, and the limestone decking connects the poolscape to a new outdoor kitchen that replaced a battered rolling barbecue.
Then there was the fun part in the form of a new waterwall that was to complete the adjustment of the outdoor environment.
For some time, Scott had been thinking about ways to replicate the experience of sitting and listening to falling rain from an up-close (but dry) perspective. Natural rain is generally not a steady pelting of a whole area: Instead, it moves in bands and waves across a space, falling heavily in one spot at any given moment before sweeping on to another, not necessarily adjacent spot.
The water wall he designed stretched for 35 feet along the edge of the pool. To cover that much area, our team set up split outlets for each of the manifold’s eight heads and mapped where we’d connect each of the 16 outlets at the wall to a four-inch pipe we’d use to distribute the water in a random pattern. We then took the 35-foot section of pipe and, using a drill press, cut quarter-inch holes with precise quarter-inch gaps between them.
The pipe isn’t pressurized by the 16 evenly spaced outlets at the pump speeds we tested, so the water introduced to the four-inch pipe drops to the nearest run of holes and flows out quickly, localizing a stronger flow to spans of about two feet across (or less) in each case. The flow through the eight-port valve is completely adjustable through the use of a variable-speed pump, so the effect can be altered according to the clients’ desires. As a result, with the pump at low speeds, the water flows out with the sort of random rainwater effect we were after. At higher speeds, the flow fills the four-inch pipe more or less completely, so the random look vanishes in favor of a strong, steady flow.
Through experimentation, we found just the right flow to achieve my desired effect and identified it as one of the presets for the pump. The client can work around that target at will.
As for the wall itself, we surfaced it with stone pieces set with irregular profiles, adding dimension to the sound of the falling water and preventing any excessive monotony when the clients crank up the flow.
The thing about this rain effect is that it’s subtle. Because the flows are randomized at 16 places along the pipe, two at a time, it’s difficult to develop a sense of pattern that makes for the sort of mesmerizing experience found with, say, the side-to-side waves of the water wall at the Aria Resort & Casino in Las Vegas. The intention here is more about integrating sight with sound: The noise made by the falling water attracts the focus of the beholder to an area of heavier flow for just a second or two before the sound and visual effects move to a different spot. That’s why the videos we’ve made are inadequate: They don’t let you target the sound the way you can in person, so the changes in flow don’t show up as urgently as they do when you’re sitting there on site.
The homeowners’ new backyard is so special that they’ve decided to stick around to enjoy it. They love the shallow lounging area, the outdoor kitchen, and the decks as much as they do the pool and spa, but their special favorite spot is the little in-pool table placed opposite the water wall: It’s the perfect place to relax with a glass of wine and listen to the rhythm of the falling rain.