Not-quite-five-foot Jo Hanson, soft gray eyes sparkling, demonstrates the high-pitched staccato trill made by male toads in spring near her water garden.

"And before long, here came six girl toads from the neighborhood, leaping up the driveway, through the garage, and out the back door," she said, laughing and pointing out their path to her quiet pond. We crouched on hands and knees on the large stones at the edge, noses near the water to peer beneath its surface.

"See those little tadpoles swimming around the hyacinth roots?" she said, indicating the shiny half-inch-long black swimmers. "The girl toads stayed to lay their eggs in the water, then went back home. Those babies will become tiny toads and leave the water in a couple of months. I love to have them living here; they eat bad bugs!"

Hanson, a 69-year-old Overland Park resident, was one of the 92 founding members of the Kansas City Water Garden Society, which began 18 years ago, and she is community service projects chairwoman.

All around the city, Water Garden Society members are preparing for the 17th Annual Kansas City Water Garden Tour this month. It's one of the largest of its kind in the United States and is the main fundraiser for the society's community projects.

The members design water gardens at area schools and nursing homes, about 60 across the city. To receive the benefits of the society's expertise and effort, all a facility need do is contact the society. The members teach from beginning to end about the philosophy, science, and engineering involved. A major benefit of society membership is the annual members-only plant trade, intended to help members get new ponds started. But much of the pot-bound growth is also donated to these institutions.

Hanson's driveway holds an ad hoc collection of pots and cut-off barrels, each containing sprigs or clumps of water plants—yellow flag iris, scouring rush, floating hyacinth. Hanson uses the plants every spring to train science classes in her garden.

Hanson introduced a long-time neighbor, Aggie Hunt, who admires Hanson's garden. But Hunt, 85, can't manage the maintenance required, so together they designed and installed a "bubbler"—a large potato-shaped rock about 1 foot wide and 1.5 feet tall with a hole through the center. In an intimate fenced garden at the entrance to Hunt's home, it sits over a buried 50-gallon basin covered by a sturdy grate and hidden by small river rocks. An electric pump recycles water up through the rock and it slips down the surface, glistening and gurgling.

Hunt loves her ritual of morning coffee and a crossword puzzle at a small table a few feet away. But this pleasure doesn't stop at summer's end. Her breakfast nook is just inside and, through her window, she watches water skim over the rock's surface, forming ice sculptures as it freezes and splashes like a winter stream.

According to Hanson, the society recommends that a pond be about 13 by 18 feet in size and 2 feet deep, with a pump and waterfall. Costs vary, depending on design and how much work the residents do themselves. Hanson says people should join the society before they start a pond.

"We have checklists and lists of approved contractors to keep people from making big mistakes," she said. "If it's not done right, it usually can't be fixed; it usually has to be torn out and started over."

A nice water garden can cost $1,500 if you do the work yourself or up to $6,000 if contracted out. A bubbler needs very little maintenance and can be achieved for much less, between $250 and $500. The society recommends bubblers for small areas and for older people who can't manage pond upkeep.

The society's 700 members, many of whom are older adults, sign up for volunteer projects. Some perform regular maintenance on the water features at the Kansas City Zoo, and they often supervise exhibits at the Home Remodeling Show and the Flower and Garden Show. The group produces a monthly newsletter and has monthly meetings September through May at the Discovery Center.

Ponds of society members are chosen for the garden tour each year. They range from charming small gardens to complex gardens with bubbling streams, waterfalls, bridges, and huge plants, akin to a rain forest. A bus tour is available if you want to see all 43 gardens without driving.

Many deep friendships form around this engaging hobby. Some members tour the country together, sometimes in motor homes, cooking and fishing and visiting famous gardens and lakes. Many other members, like Hanson, love sharing their passion and knowledge—and one thing is for sure: You'll want to get in touch with them if you want one of these delightful environments at your home.