Dry spell: they may seem like a contradiction, but dry streams make perfect sense if you create the right illusion

Pool & Spa News, April 23, 2004 by Rebecca Robledo

Here's a quick pop quiz: What function does a stream without any water serve?

A. Covers up drainage areas in an aesthetically pleasing way.

B. Brings homeowners closer to nature in a drought-friendly environment.

C. Creates an outdoor work of art.

D. Tests builders' skills in rock placement.

E. All of the above.

If you answered "E," you're correct. While some people can argue that dry streams are not as beautiful as their wet counterparts, most can't deny they make bold statements when done properly.

Dry streams are formed using the same rockwork as their wet cousins, but they contain a dry material in place of water. Usually, gravel or pebbles are used to evoke the image of water, though sometimes designers put in ground-covering plants.

No water means no worries about containment, leak-proofing and hydraulic design. You just need to be sure you bury the rocks deep enough in the ground to stand stable and look believable. Then place a landscape fabric under the stream before laying the gravel down. This helps keep soil from moving up through the gravel and into the stream.

While these techniques simplify construction, it's still up to the designer to paint a picture of water in the viewer's mind. But with the right touches, and careful choice of pebble filler, you can create a masterpiece.

Realistic design

Artists utilize out memories to convince us that we see something when it's not present, says David Slawson, a Japanese-garden designer and author of Secret Teachings in the Art of Japanese Gardens. This also happens when you imitate nature, whether you have water or not. With a dry steam, however, you're missing a vital component, so it becomes more difficult, almost like a game of connect the dots.

"The dry landscape works even more powerfully on the basis of illusion, which means that your mind is filling in the blanks," Slawson says.

He likens it to a painting or a drawing with just a few strokes. "If it's done well, you can capture a caricature of a person's face, for instance. In the same way the dry landscape, if done well, can capture the quality of various aspects of a landscape, such as a waterfall coming out of some hills."

To do this, use single large rocks instead of piling smaller specimens. Include plants, islands and different elevations. Don't build the streams straight or flat. Let them meander, narrowing and widening as they do in nature, says Tire Hansken, a landscape designer with Galaxy Landscape Co. in Occidental, Calif.

"In broad turns in a stream bed, the inside curve will be a sandbar or bank, and the outside curve will be stone," Hansken says.

Large rocks should indicate waterfalls or even multilevel cascades. Choose them as if they are going to direct and sculpt the water. You should even place berms, plants or bends to hide the "source" of the "water," just as you would with a wet stream.

When working on dry streams, designers have a tendency to skimp on some of these important details. For example, some builders place the gravel at the same elevation as the banks. Because there's no water to hold in, they should place the material directly on the ground.

"You want the gravel sunk in," says Bill Castellon, owner of Bill Castellon Landscape Service in Oakland, Calif., and a Japanese gardening instructor at Merritt College in Oakland. "It leaves a better feel and it's more believable." This also helps contain the aggregate so it doesn't get blown out.

Color and texture

If the dry stream were a painting, the boulders would be your major brush strokes. The material used to fill the stream adds the final artistic touch, reinforcing the exact illusion you're trying to create.

Look at the aggregate's color. Strive for one that contrasts with the rocks you've used to outline the stream, Hansken says. Don't use dark gray gravel with dark gray boulders, or tan and tan. You could also use more yellow or pale orange gravel to offset brown or gray boulders. Dark Mexican river rock can accent the banks and offer a nice contrast to the paler gravel.

Hansken tries to avoid using brown materials. "Brown is a murky color," he says. "It's like putting soil in your water." On the other end of the spectrum, white marble is just too bright and polished to look realistic. He prefers the less slick granite over marble.

Choose textures that create the surface you're trying to evoke. Wider streams tend to run more quietly, so you want the illusion of slow-moving water. In this case, Castellon uses smaller, finer-textured granite for a calmer, smoother surface. In choosing a variety of stone, moss rock works well for imitating slow water, he says.

Faster-moving "water" occurs in narrower streams. Mixing larger pebbles with a fine material gives the appearance of turbulence by breaking up the surface. Turbulent streams tend to be shallower, exposing smaller rocks or boulders lodged in the bottom, so scatter much smaller versions of the outlying boulders among the gravel/pebble mix. River-washed pebbles look authentic as a filler material because they were actually created by fast-moving water.