The Wetlands,
your indoor garden...
The wetlands are an important part of the Earthship concept. All the wastewater (other than the toilet) is drained into these structures and used to grow your indoor garden. Excess water can even be filtered through the wetlands and used again.
The walls of the wetlands are built using old cans or bottles, these serving as air gaps in the concrete leaving a very strong "honeycomb" support structure. The plumbing drains are then fed into the wetlands at one end, the unit sloped away so that water entering will flow downhill (through a mixture of stone, sand, charcoal and dirt) being purified along the way.
Our home has two wetlands, one at each end of the "face" area of the building. One receives the water from two sinks and the shower - the other from the kitchen sink and the washing machine.
The above grade surface of the wetlands walls can be finished as you like. Typically these will receive a smooth adobe finish similar to those of the interior walls. Our wetlands are not yet completed, but you can see that a few "volunteers" have already made themselves at home.
Just to give you a sense of what they may look like when completed, we borrowed this picture from another completed Earthship (below right).