The aptly-named Black Mountains behind my home have been turned a beautiful shade of green by recent and relatively abundant rainfall. Even a brief rain event in Southern Nevada is welcome, but the last month or so has been exceptional and it has me thinking of potential opportunities. Each time I see water dripping off my roof or running down the gutter, I think of the lessons I’ve learned from architect and visionary Michael Reynolds and his revolutionary Earthship structures, as well as Brad Lancaster and his excellent series of books, “Harvesting Rainfall for Drylands and Beyond.”
For example, Reynolds’ homes harvest rainwater, store and filter it onsite, then reuse every gallon up to four times before returning it, relatively clean, to the environment. Lancaster’s common-sense ideas about water harvesting are equally beneficial. I like to think that the long-term solution to our water issues, and our quest for sustainability, lie in adoption of concepts like these rather than the business-as-usual, environmentally-destructive approach of massive engineering projects (think pipeline) that move us in the opposite direction.
Here’s how an Earthship water system works. The roof is used to gather rainwater which flows through a natural filtration system before being stored in a cistern. A pump and modern filtration system sends potable water to a pressure tank to provide conventional household water for bathing, washing, cooking, etc. That is beneficial use #1. Then the fun begins.
Each Earthship has a built-in biological graywater treatment and containment system, or in layman’s terms, an interior, lined, sealed and plumbed planter. They typically run along the south side of the home near south-facing windows that provide plenty of light and warmth. These systems are full of plants that clean the air and water while providing an aesthetically-pleasing feature to the home. In certain cases they may even grow food. Beneficial use #2.
Next, the cleaned graywater is used for flushing toilets, putting an end to the ridiculous but currently accepted practice of flushing with potable water. Beneficial use #3.
Blackwater is sent to an outdoor biological filtration system that creates odor-free green space, filtering and cleaning the water before sending it back to the environment for further irrigation, or via pipeline to Lake Mead. Look no further than the Springs Preserve to see an elegant and natural water treatment system in use every day. The system is described as “a beautiful onsite waste-water treatment system. The system included a primary treatment tank, constructed wetlands, a recirculating sand filter, mechanical filtration equipment, and an irrigation system. The system was designed to produce reusable water from the blackwater collected in the Springs Preserve buildings. The treated grey water is reused within the Desert Living Center and the gardens to reduce potable demand.” Beneficial use #4.
When coupled with Lancaster’s simple, proven techniques to naturally enhance on-site irrigation (read his books to see what I’m talking about, especially if you are a commissioner, council member, city planner or state water engineer), we have the potential to make a serious dent on our need for fresh water from the Colorado River while also cleaning up our water supply and reducing the massive amount of energy we currently use to pump water throughout the valley.
Our average annual rainfall is only four inches, but we could do a lot with that by implementing a long-term vision of transformation. Let’s use a home with 2,000 square feet of roof area on a lot of 7,500 square feet for this example. Let’s further assume that our codes have been wisely improved to allow these techniques and even to harvest irrigation water from the sidewalk and half of the street, a resource that is available in front of every home (remember, this is a long-term vision). With just our average rainfall and the multiplier of beneficial reuse for all indoor water use, we can potentially save 40,000 gallons (or more) of water annually per home. For a home that now uses 85,000 gallons from the water district, the reduction is significant and could even exceed 50%.
Retrofitting our existing housing stock to make use of these concepts would require a lot of money, but so do expensive pipelines. Unlike the latter, deep-green efficiency moves us toward sustainability. It can also provide a lot of local jobs: landscaping, plumbing, carpentry, horticulture, and local food production are but a few I can think of. We also benefit by reducing our flood potential, saving lives and property. Our biggest liability can become our greatest asset, improving our economy as well.
Successful green living is the product of vision and action. Think about it.