WATER SERIES POST 3: The Red Submarine Solution

Written by Todd, Homeowner

Local geology, climate, our living habits, and the house’s legacy garden collided to make the Water Petal the biggest hurdle for us to leap. The last in our series about the challenges of meeting LBC’s Water Petal.

Anyone could spot Anne James’s deep care for gardens.  Anne almost always shows up with a broad smile and a high laugh.  She purrs when she stands next to a delicate planting. Her eyes firm when she talks about protecting the roots of old trees. And when she wants a large invasive plant pulled out of the ground, her skipping laugh descends, and she growls, “Can someone put a chain on that thing?!”

We saw her determination as we wrestled with the LBC’s water petal.  The goal of the Challenge is to meet 100 percent of our water needs without relying on the city system.  The big question was this: how could we and the garden make it through the summer when almost no rain falls?  To store enough to bridge those dry months, we were faced with installing an expensive 30,000-gallon concrete cistern, which created its own massive carbon footprint and invaded the natural, shallow water table. “The Water Petal is always the hardest,” Miller Hull principal Brian Court often reminded everyone.  We were learning how true that was.

Instead of finding cheaper ways to store water, can we reduce the cistern size by further reducing our irrigation? From an airplane flying over, this doesn’t look like a problem.  Mature native evergreens create a lush canopy for the property. The native evergreens live perfectly well in our climate. But they are underplanted with ornamental Japanese maples, flowering trees, rhododendrons, and small shrubs and groundcovers, all of which have matured beautifully over 50 years.  These plants below require water in the dry summer months to stay alive.

Anne, was our first line of defense. Unlike many designers today who draw their plans on a computer, she works a pencil on a garden design like the ancients worked levers on large stones. Small movements, big changes, all hand done. Draft #2 of her design and water estimates emerged. This plan involved separating thirsty plants from the drought-tolerant ones and creating distinct irrigation zones so that nothing received more water than necessary.

Good effort. But the LBC required us to add food crops to satisfy the agriculture mandate, sending us further in the wrong water-use direction. Draft #2 wasn’t enough, and we still needed the concrete cistern.  She returned to the pencil. Draft #3 sent Anne’s voice downward, near the growl register.  She feared we would starve the existing garden.  And our new vegetables would wither. Anne and our architects John MacKay and April Ng have a wonderfully collegial relationship. But a tension entered our conversations about meeting the water goals.  

Meanwhile, Todd turned to his favorite coping skill, denial. He retreated to the previous step in the water-storage process, feverishly searching the web for inexpensive and attractive cisterns.  That time was not well spent.

No Small Feat: Anne James drew by hand the existing garden and then inserted new plants grouped by watering needs.

Finally, after a lot of false starts, we came up with a compromise and a plan:  We begin by meeting the home’s potable water needs by catching 36,000 gallons of rainwater from the roof and storing some of it in a relatively svelte 10,000-gallon tank. When dry midsummer comes and the garden needs more than our greywater provides, we supplement the garden irrigation with city water.

Under Anne’s redesign, the garden used 25 percent less water, about 72,000 gallons, even with our added agriculture. Of this smaller amount, half was recycled from the house. The other half came from the city system, or, more precisely, Bainbridge’s aquifer.

In the end, we reduced our projected water consumption from the aquifer by nearly two-thirds – from 100,000 to 36,000 gallons, and we immediately sent it, naturally filtered and cleaned, back to where it started a thousand years ago. This was our best effort at balancing practicality, the impact on the land, the impact on the Puget Sound and the garden’s legacy.

Would this eliminate us from LBC certification? Miller Hull’s Chris Hellstern laid out our case, and the folks at ILFI, to our relief, agreed.  They understood that a huge concrete cistern with a vast carbon footprint and prohibitive cost clashed with the LBC’s own goals.  And they recognized the diligence Anne, Biohabitats and Miller Hull brought to solving the problem.  (The Living Building Challenge, which is wonderful about improving itself whenever it learns something new now seeks to address the rigorous Water Petal requirements in a more holistic way.)

Biohabitats’ plan harmonized our water needs with the aquifer and the land’s water cycle.

Karen assessing the excavation: “When can I drive?!”

The ILFI recognized that our land could support the water cycle that existed before a house landed there, and we could fulfill our responsibility to care for a landscape that had thrived for a half century and more.  Anne’s careful work – her willingness to distinguish between water-loving and water-saving plants and her eagerness to lever her pencil again and again, organizing plantings, selecting drought-tolerant new plants, and arranging them all in an aesthetically pleasing way – in the end, led us to an effective compromise

The LBC has a “scale-jumping” provision, which allows someone to mitigate an environmental impact on another site, where it is more feasible.  As a last resort, owners who need, say, agriculture on their lot to meet petal requirements, can create it on some other site nearby.  While scale-jumping doesn’t fix the bigger problem – in this case our world’s lack of water self-sufficiency – it gives much-needed flexibility.  The LBC required us to create a water offset for what we drew from the city. (That project will be the subject of a future post.)

Tomb of Xerxes, c2019 CE.

When the day came to install the cistern, a tank looking like a big red submarine floated down our narrow road. A crane lifted its 10,000-gallon mass from the truck and lowered it into the hole. Burying a smaller cistern felt to us, in itself, like a massive undertaking.  But now we stand ready, with Anne’s help, to harvest the aquifer in the sky to good effect.

Perhaps the real value of this long process was that it showed us what we were taking from the ground, what we were putting back and the difficulties in balancing the two in our climate. The Pacific Northwest gets rain so regularly in 3 out of 4 seasons, a home doesn’t have to store much to deliver water most of the year.  A small cistern will find itself continually refilled. But those three months of summer drought. They’re murder.

By stretching to pursue a standard as difficult as the LBC Water Petal, we can see a way to address our region’s water woes affordably. The most practical approach for most homes would be to settle for a slightly different “sweet spot” than we did.  An inexpensive system could take advantage of the Northwest weather to vastly reduce, even if not completely replace, our water footprint.  We asked Biohabitats to use the learning on our job to design an affordable setup for a home that could be installed simply and inexpensively in many houses. We hope that the design, which covers about 80 percent of a family’s water use, will help others. If everyone reduced their water use by even half that, we’d tremendously improve our aquifer and the Puget Sound. 

Written by Todd, Homeowner