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Karen “K.B.” Bailey, garden steward of Boxerwood Gardens, grasps the greenhouse handle — itself a cast-iron hand grasping a sculpted, botanically-themed handle — and opens an artistically wood-reinforced door to a different world.

On the left side of the domed space, tropical plants, grown gigantic after feasting on water-borne nutrients, lift leaves into a humid atmosphere which, on a winter day, hopelessly fogs glasses and camera lenses.  Near huge philodendron leaves and parallel-veined banana fronds, an impatience plant bursts with health — and with glowing, magenta flowers — while a 4-foot-tall ginger plant proffers white blooms sweet-scented as any gardenia.

Across the greenhouse, separated by a narrow walkway, is another mini-oasis, where water, splashed by fountains and sprays, dallies beneath more philodendra before flowing through a pipe into a fern-bordered fish pond.  Colorful carp flicker and weave restlessly in the depths, testimony to the healthiness of their watery world, and a shy, green frog hides, waiting his chance to emerge and feast on clouds of tiny dancing insects.

Paradise found?

Yes — and no.

 An apt acronym

The greenhouse and all that’s in it are actually a “constructed wetlands,” the next to last stage in Boxerwood Gardens' recently installed Nature-Emulating Waste Treatment System, or NEWTS.

That acronym, reinforced by the system’s logo of two spotted salamander circling each other, seemed particularly apt this winter, when newts and other amphibians, like the frog in the fish pond, moved into the wetlands for warmth, water and food.

NEWTS, which uses microbes and plants to digest and remove nutrients in waste, was built in 2004 to replace Boxerwood’s small, conventional septic system.  The new system processes all human, as well as other kitchen and bathtub, waste originating in both the increasingly used lodge nature center and the Orchard House, a smaller permanent residence.  Taking the purification process much further than septic tanks, NEWTS transforms waste into “resource,” mainly remarkably clean water.

Besides its practical and environmental benefits, NEWTS is also a teaching tool, as befits an educational center.  Indeed, since August 2004, as many as 2,500 people, from area school children to garden club members and even wedding guests, have toured the system and learned about alternative waste treatment.

Visitors last August included over 80 participants in a tour, sponsored by Healthy Foods, of five alternatively constructed homes.  While four of the homes contained composting toilets, which use both oxygen to hasten decomposition and fibrous material to soak up some liquids, and the fifth boasted a particularly scenic outhouse, none offered the cutting-edge technology — so new, and yet as old as Mother Nature herself — of Boxerwood’s NEWTS.  Indeed, there are only a handful of systems like NEWTS in Rockbridge County, and none with as full an array of components.

 How it works

Along the NEWTS “trail,” visitors may follow a series of signs, many mounted on ring-patterned, naturalistically shaped planks of wood, leading from Munger Lodge through a series of treatment stations and ending in a rain garden.

The first sign, located just north of Munger Lodge, the former home of the family of the late Dr. Robert Munger, is entitled “Wastewater Source.”  An illustration shows a schematized drawing of the house, with two bathrooms and a kitchen sink, while the text explains that the lodge is host to thousands of visitors each year who, along with nature center staff members, use water in the lodge in a variety of ways.

“All this water goes down the drain,” the sign reads, “but it would be irresponsible (and illegal) just to put it in the ground.”  Viewers are then asked to think of three reasons why doing so would be irresponsible.

Second stop is the septic tank, located underground but marked by another sign.  Here, a picture shows three levels of waste inside the tank.  At the bottom is a “sludge” level, where anaerobic digestion, or digestion without oxygen, occurs, like that which happens “in our gut,” as the sign explains.  On top is a layer of “scum, namely grease and fats.”  Between these two levels is clearer, partially treated water, or effluent, and it is this water which, after remaining in the tank for between one and two days, is piped to the next stage for further treatment.

Visitors now walk a few more feet to learn about another underground installation, the pumping station, to which water from the septic tank flows by gravity.  When water reaches a certain level in the station, a pump switches on, sending the water up to the media filter, above-ground, concrete boxes containing three grades of gravel through which the wastewater is sprayed, then passing slowly across surfaces covered with microbes which digest and metabolize the pollutants.  The wastewater seeps through the gravel filter several times by means of a distribution box, which allows one-fifth of partially treated water to be piped on to the greenhouse, but sends fourth-fifths of it back to the pumping station and through the filters again.

Having learned this much, NEWTS visitors entering the greenhouse understand that this is no simple growing environment, but rather a functional, if highly attractive, stage in a “living machine.”

In the greenhouse, water from the distribution box flows into two lined ponds, a “subsurface constructed wetland” and a “free surface constructed wetland,” both filled with gravel and supporting aquatic vegetation.  In summer, reeds, sedges and bulrushes, the “real workhorses” in the greenhouse, according to Bailey, feed on and remove wastewater elements such as nitrogen and phosphorus and even take up heavy metals and other toxins they may find in the water.  After these plants die back in winter, tropical plants take over, doing the same work.

Water, now filtered and cleaned by the plant roots, is piped slowly from the subsurface pond through an ultraviolet light disinfection element, which kills almost all remaining bacteria and viruses, and then enters the “free surface” wetland by means of fountains and sprays.  These allow the water to absorb dissolved oxygen, making it a richer resource for living beings downstream.

Water from this wetland, now filtered, disinfected and aerated, enters the fish pond where the carp are not just pretty fish, but rather aquatic “canaries in the coal mine,” attesting to the purity and oxygenation of their surroundings.

Water from the second wetland may also be used to water other plants in the greenhouse or may be discharged into the rain garden outside on the hill below.  During last August’s tour, a ruby-throated hummingbird hovered over the rain garden, sipping nectar from a cardinal flower — the happiest of end-users.  

Unique in Rockbridge

Boxerwood’s system is the only one like it in Rockbridge County , said Hunter Mohring during a recent talk in her office at Munger Lodge.

“Ours is the only one that has the dual components of media filter and greenhouse,” she explained.  “It’s overkill, really, but we wanted to be able to demonstrate both methods.”

Also unique is the system’s educational use, she said.

“Other people install their systems and then, essentially, turn their backs on them.  We made ours educational, so the public can see it.”

On this day, the garden’s executive steward is especially pleased with the system, having received its annual test results from a government-certified lab.  The tests, performed on samples taken from a pipe near the end of the system, showed reassuringly low numbers in a range of indicators, including Biological Oxygen Demand and Total Suspended Solids.  Also gratifying were the samples’ ph levels, which were within the normal range, and, most important for public health, levels of fecal coli form.  These were so low they couldn’t be measured, Mohring said.

Noting that Boxerwood’s original septic system, the familiar underground tank and lines, was built in the 1950s to serve a family of five, Mohring explained that the old system soon became inadequate for the hundreds of visitors the nature center sometimes has on a busy school day.  Actually, the old system was “failing” from the beginning, she said, since it was located on land that didn’t perk.

“Perk,” short for percolation, refers to a soil’s ability to absorb water.  While all soil types have some ability to absorb water, not all perform that function at a rate that enables the soil to provide adequate treatment for waste.

“Because of our karst geology in Rockbridge County , we have to perform a balancing act between two problems, one when the perk rate is too low and the other when it’s too high,” Mohring explained.  “Both conditions exist in the county, and we can have both extremes in the same place.”

An illustrated sheet in her office showed how a heavy layer of clay in the soil can prevent draining and result in surface and ground pollution.  At the other extreme, porous limestone — prevalent in the county — with its sinkholes, caves and fissures, can mean quick contamination of ground water due to inadequate filtering by soil.

“Though we’re part of the [Chesapeake Bay Foundation’s] Save the Bay, we needed to protect our own watershed, not just the Bay,” Mohring continued.  “This way, we’re protecting both.”

Mohring first heard about processing waste by “mimicking” nature many years ago during a visit to the Findhorn community in northern Scotland .  A few years later, she attended a conference in Massachusetts where one of the creators of the first “living machines” was a speaker.

“I was enthralled with the idea of copying nature to process waste,” she said.  “Now that I knew about it, I met with a local engineer, who was dubious at first but then ran into John Schofield [of the local office of the Virginia Department of Health] who said, ‘Yeah, we could do it.’”

From then on, NEWTS was a go.

After drawing up a rough schematic, Mohring submitted the plan to the Department of Environmental Quality, which oversees above-round discharge systems of this size.  The health department oversees below-ground systems and single-family, above ground discharge systems.

Given five years by the DEQ to install the new system, Boxerwood did it in two.

Now, NEWTS is maintained by both Bailey and Mohring, and Mohring, who served as contractor for the system, has also completed and submitted for approval by the DEQ an owner’s maintenance manual, complete with detailed maintenance schedule and list of contact names.

 “I’ve been involved in every inch of the [NEWTS] system and every drop of water that comes from it,” she said with satisfaction.  “I’ve learned a lot — and most of it is exciting.”

As a result of her familiarity with NEWTS, which can only be called intimate, she was recently asked to serve on a regional task force on alternative, on-site waste treatment systems, organized by the not-for-profit Canaan Valley Institute.  

‘No away anymore’

From Mohring’s office, it’s a short walk back to the greenhouse for one last look — and another chance to take in its tropical ambience, a welcome contrast to the snow outside.

Inside, warm air is blown through the two layers of the greenhouse’s plastic covering and a heater guarantees a minimum of at least 50 degrees Fahrenheit. Today, also, the sun gleams through the layers, adding its share of heat.

Bailey, looking over the plants in the constructed wetlands, commented that she planned to set aside a day soon to trim back summer’s reeds and other temperate-zone plants.  Suddenly, she turned to the reporter with an intense expression.

“You know, taking care of waste, whether it’s trash or biological waste, is an increasing problem on our planet,” she exclaimed.  “People used to think that they could just throw, or flush, it away, but there’s a problem with that.  Where is away?”

She flung an arm wide to take in the greenhouse and the world beyond.

“There is no away anymore,” she declared.  “We have to be responsible about the sewage issue, especially in Rockbridge County , where every rock has a crack, and every crack eventually leads to ground water.

“This system isn’t perfect,” she finished.  “Improvements are being discovered all the time.  We’re just doing something.”