Practical purpose

September 18, 2011 at 12:00a.m.

Waterfall doubles as eco-friendly reservoir

McClatchy Newspapers

GREEN, Ohio

Karen and Bill Hoffman’s new waterfall has a serious side.

Sure, the waterfall is beautiful, tumbling down the Hoffmans’ sloped front yard in Green. But the aesthetics disguise its practical purpose: It’s a rainwater harvesting system, designed to capture runoff and hold the water for reuse.

Think of a rain barrel, only bigger and prettier.

The pondless waterfall is just the decorative part of the system, which catches water running off the Hoffmans’ roof and sends it into an underground reservoir. There the water is constantly recirculated to feed the waterfall, but it’s also available for watering plants, washing cars and other uses that don’t involve drinking it.

That will save the Hoffmans money on their water bills as it benefits the environment, noted Jeff Weemhoff, president of Atlantic Water Gardens, the Mantua company that manufactured the system’s components and oversaw its installation.

Karen Hoffman said her main motivation for adding a waterfall was to cover the traffic sounds she can hear through the couple’s bedroom window. After all, her husband, Bill, is in the water-feature business: He owns both Pond Supplies of Ohio, a wholesaler of water gardening equipment, and Hoffman’s Garden Center, which caters to do-it-yourselfers who want to build ponds and other water features.

Making the waterfall functional and green as well as decorative didn’t involve that much more expense or effort, so it only made sense, she said. “I mean, why not?”

The Hoffmans also used the installation as a sort of on-site classroom so Pond Supplies’ landscaping crew could learn how it’s done.

Instead of flowing into a pond, the waterfall pours into a gravel bed that disguises a reservoir below. The reservoir is a 7-by-8-foot, 35-inch-deep hole in the ground, lined with a rubberized material and filled with two layers of porous plastic blocks called Eco-Blox that support the gravel and some larger decorative stones.

The blocks, which look a little like plastic milk crates, were used because they provide much more strength than just covering the opening with a grate, explained Atlantic’s rain harvesting sales manager, James Lavery. A layer of landscape fabric over the blocks keeps small stones from falling through the openings.

The reservoir is fed by an underground plastic pipe connected to the Hoffmans’ gutter system. When it rains, water coming off the roof flows down a downspout on the side of the house, through a diverter and into the feeder pipe.

The diverter doubles as a filter to keep debris out of the reservoir, Lavery said. Flexible plastic fins bounce bigger pieces of debris out an opening in the front of the diverter, and a screen catches smaller pieces.

The diverter is also designed to allow the first flush of water coming off the roof to bypass the reservoir and go straight to the storm sewer. Dirt, bird droppings and other contaminants are washed off the roof in the first couple of minutes of a rainfall, Lavery explained, so the system lets the first eight to 12 gallons pass right through an opening in the bottom of the diverter and into the sewer drain.

Absorbent rings near that bottom opening swell as the water passes through them and push on a stopper, sealing the opening after about two minutes. The water is then redirected into the pipe that leads to the reservoir.

If the reservoir reaches its 1,000-gallon capacity, an overflow pipe will send any excess to the storm sewer, Lavery said. Should the water level drop, an auto-fill device would refill the reservoir from the municipal water system.

The reservoir has two energy-efficient pumps, one that operates the waterfall and the other that pressurizes the water to about 65 pounds per square inch, comparable to household water pressure. That pressurized water feeds a 1-inch outlet to which a garden hose or spigot could be attached.

Lavery said the Atlantic system costs about $2,700 to $3,500, depending on its capacity.

But since much of the work involved in installing the rainwater harvesting system has to be done anyway when a water feature is installed, the system doesn’t necessarily add that full amount to the cost of the water feature, he said.

“It’s an easy add-on to something people already do,” Lavery said.

And it makes going green just that much more attractive.