Last Sunday I visited the Alaskan Eco Escape Permaculture Center, Alaska’s only bioshelter. A bioshelter is a solar greenhouse managed as an indoor ecosystem.
As an educational center, the bioshelter hosts permaculture workshops and various other custom events. It is also home to permaculture instructor, Cindee Karns, and her husband, Curt. The couple has lived there for five years since purchasing it from the original builder. They still consider the bioshelter a research facility. “I think every year we live here without getting sick is research,” Cindee said.
Funded by a federal grant in 1987, Bob Crosby built the bioshelter as a low-tech demonstration of a house without a well or septic system. However, the government ultimately declined to use the design because Crosby’s clever water filtration system cost $5,000. Cindee noted that installation of a water and septic system today costs around $50,000.
To filter and reuse the house’s greywater, the bioshelter’s water filtration system utilizes a solarium—essentially a large greenhouse space complete with lush vegetation, potted apple trees, and golden coy fish swimming in the pond. The bioshelter’s website has a great video with more detail about the solarium. So for this post I will focus on the water filtration system (pictured above).
All the house’s greywater (shower, sinks, washing machine) is piped into a 55-gallon plastic barrel in the basement. This fill tank is elevated above the two other tanks, all of which have an emergency overflow pipe. At the bottom of the fill tank is an upside down paint can connected to tubes from a simple home aquarium air pump. Dials on the air pump allow users to control the air flow which burps water into the next tank about every five seconds.
The next tank, called the settling tank, is another 55-gallon barrel. Sediment collects at the bottom and must be emptied every three to five years. Water flows from the top of the settling tank into the clarification tank, a third 55-gallon barrel.
While good bacteria are present in each of the three tanks, most of the bacteria live in the clarification tank where it breaks down many of compounds and particulates in the greywater. Without oxygen, the bacteria will die, as happened once when Cindee turned off the air pump while out of town. However, the bacteria can easily be restored using a common product called Rid-X.
In the bottom of the clarification tank, another upside down paint can connected to air tubes burps water up into a bucket on top of the tank. The bucket is filled with geofabric and a type of furnace filter made of hog hair and coconut husk, all of which serves to catch any particulate as the water passes through back into the settling tank.
The water continues to circulate back and forth between the settling and clarification tanks for 15 days or more depending on the inflow of greywater into the system. When the water in the clarification tank reaches a certain level, a float valve sends the water to the solarium pond where the non-edible fish test its purity. Cindee admits to having killed two sets of fish in the process of finding suitable cleaning products. She now used Nature’s Gate shampoo, Dr. Bronner’s soap, 7th Generation powdered dishwashing soap, and BioClean laundry detergent.
The water stays in the pond until it rises to the height of an outflow pipe which drains it into the surrounding gravel wetland. That wetland also holds rainwater collected on the roof.
From the wetland, water is pumped through a UV filter and into two 5,000-gallon storage cisterns. Between the cisterns and the faucet, the water passes through a sediment and carbon filter. Just to be safe, Cindee uses a final 5-micron filter on the faucet for her drinking water.
To reiterate, here is a basic overview of the eight steps that the water passes through:
greywater—>fill tank—>settling tank—>clarification tank—>solarium pond—> gravel wetland—>UV filter—>cistern—>sediment and carbon filter—>faucet
The question is: by reusing their water and supplementing with collected rainwater, does the bioshelter offsets the costs of its maintenance? The short-term answer is yes. Water in the nearby city of Anchorage costs $90/month no matter how much you use. The bioshelter system requires electricity to run the pumps, but other than that there are no substantial monthly costs. However, the rainwater-collecting roof needs repairs estimated at $25,000. Thus, by being an unusual system, specialized repairs are often expensive in the long-run. If only the water filtration system were more common.
Cindee and Curt say they will continue to live in the bioshelter and run the Alaskan Eco Escape Permaculture Center. Would they recommend living in a bioshelter to others? The answer is complicated.
“Once you have to take care of your own water, it becomes more valuable,” Cindee said. “Once you grow a zucchini in your converted toilet waste (thanks to the worms), you understand the true cycle we are meant to live within, not the constructed cycle of the American lifestyle which wastes all sorts of resources throughout that cycle without caring, or even knowing that they are wasting resources. So I would always recommend this to everyone, but only a few would ever do it.”
For more information on the bioshelter’s water filtration system, visit Bob Crosby’s company website: http://biorealis.com/biofilter/drumbiofilter/