From Organic Spa Magazine:

Designed for a family that loves to play in the pool, this luxurious, green-built grotto will endure for generations.

By Laurel Kallenbach

When a Wilmington, Vermont, family asked architect Joseph Cincotta of LineSync Architecture to design a swimming pool where they and their young children could relax and play, Cincotta dug deep—literally. He created a cavern-like grotto that naturally blends into the woods around the owners’ home, which overlooks Lake Whitingham.

Partially burrowed into the hill, this wood-and-stone grotto encloses a 40-foot infinity-edge pool, spa pool, waterfall, splash pond, slide, sauna, steam shower and dressing room. Cincotta covered the structure with a living roof planted with sedum and native wild strawberries, which also helps insulate the grotto.

This watery playground incorporates nature’s elements: sunlight, water, wood, stone. The dark, gray-blue schist that dominates the grotto was quarried just 50 miles away and installed by local masons working. Western cedar and southern yellow pine for the roof beams and decking came from nearby Maine.

These locally sourced materials drastically reduced fossil fuels used for transportation—and the materials themselves are already adapted to the local environment. The New England lumber is naturally resistant to area insects and rot, and wood is a logical choice for a (lightly) chlorinated area because it doesn’t rust.

“Durability is the hallmark of sustainability,” says Cincotta. Long-lasting materials don’t have to be replaced or constantly maintained, and stone doesn’t need fresh coats of paint. This grotto will look as good as it does now in 100 years.
And while it’s luxurious, Cincotta and builder Jim Lynch were conscious about conserving resources at every turn. The back wall is built into the same hill as the house, creating the ultimate insulation. The remaining doors and the glass walls (which use super-insulated SeriousGlass technology) are far more energy-eficient than code. To keep the sandstone-tile floors comfortably warm beneath bare feet during winter, Cincotta chose radiant in-floor heating—a method that also saves energy and causes less window fogging than traditional forced-air heat.

While they’re backstroking beneath the grotto’s skylights, pool guests will never guess the many behind-the-scenes energy- and water-saving methods. Heat from the sauna is piped into the pool water rather than exhausted outdoors. The slide is made from a recycled-plastic resin so slippery that it requires very little water for a smooth ride. And filtered pool water recirculates through an aerating waterfall that cascades into a 4-inch-deep toddler pool situated adjacent to the spa tub, so parents can soak while their children splash just an arm’s length away.

“When I design a project, I want it to be timeless, an heirloom—something that won’t be torn down in 20 years,” Cincotta says. “The owners wanted this pool for their children, so I designed a place they’ll pass along for generations to come.”
 
TIPS FOR A HEALTHY ECO-POOL

1. Conserve heat and water. 
Evaporation depletes a pool’s water level by 30 to 50 percent and wastes heat. To reduce evaporation:
• Cover your pool—indoor or outdoor—when it’s not in use. Solar or “bubble” covers absorb 75 percent of the sun’s heat that hits the pool surface and release it into the water.
• Add a windbreak: trees, shrubs, a fence. Be sure not to create shade, which blocks natural heat from the sun.

2. Generate alternative energy. 
Install a solar pool heater, which uses solar panels mounted in sunny spots on your roof, fence or yard. The sun heats water in the panels; it’s then pumped through a filter and into your pool to warm the water.

3. Reduce chemicals: 
Chlorine can irritate your eyes and skin, and studies link swimming in chlorinated pools with childhood asthma. Use only a fraction of the chlorine in your pool by:
• Installing an ozone generator that destroys bacteria, algae and organic debris, leaving water clear.
• Adding mineral treatments (primarily silver and copper) to decrease chlorine amounts by 50 to 90 percent.

4. Circulate water wisely. 
Pool water must pass through a filter, but pumps don’t need to run 24 hours a day to be effective. Save electricity by:
• Attaching a timer to shut off your pump for at least 12 hours a day.
• Choosing the smallest pump possible for your pool.
• Installing a solar-powered pool pump.
 
Freelance journalist Laurel Kallenbach writes about sustainability and travel.
 

Also on HuffPost: