Cleaning Water like a Marsh We live on a planet in which water covers 71% of the Earth's surface. It would seem that there is plenty; however only a tiny fraction of this water is available to us for drinking, washing, industrial processes and agriculture. About 97.4% of the world's water is too salty for our uses, and of the remaining 2.6% most is frozen or inaccessible. This leaves our global population of over 6 billion and all of the other terrestrial and freshwater organisms on Earth to use the 0.014% fresh, usable water (Miller, 2004, p. 314). With all of our uses of water, it is very important that we work to reduce the pollution of our limited supply. The World Heath Organization (WHO) estimates that 3.4 million people die of water-related illness world wide (Miller, 2004, p. 484). Cleaning out water is critical to the health of our ecosystems and ourselves.

In the early 1980's a marine biologist named John Todd found that his family had to buy bottled water because the local tap water was unhealthy. He realized that if he had been cleaning water for his fish farm with tomatoes and lettuce plants he could "bloody well learn how to purify water for people" (Lerner, 1997, p. 48). "From an engineering point of view, modern sewage treatment is expensive and fairly sophisticated. It is symptomatic of a disconnected culture. Why not instead view wastes as resources out of place?" (Todd as quoted in Ausubel, 2003, p. 23.)

Ecologist John Todd, of Ocean Arks International, and The New Alchemy Institute, is creating innovative waste water treatment facilities using "living machines." From the outset he recognized that nutrient-rich waste which can be environmentally destructive if not managed, is problematic because it is an overabundance of a resource to aquatic life. If sewage is released untreated into water systems it disrupts the ecological balance and creates incredible algae blooms, which trip off a series of effects known as cultural eutrophication resulting in a dramatic decrease in dissolved oxygen and subsequent animal death. Human sewage is especially nutrient rich because unlike cow stomachs we are very inefficient at digesting nutrients (Lerner, 1997, p. 49).

Todd's ecological purification system begins with the raw sewage entering a passive solar green house or outdoor area containing tanks inhabited by a complex community of organisms. These tanks are then connected to a system of other tanks each with their own ecosystem specializing in a particular phase of decomposition and breakdown of organic and inorganic matter in the water. After spending ten days in this filtering series of ecosystems the water flows clear into an artificial outdoor marsh or wetland to be reintroduced into the local hydrologic cycle. The water can also be rendered drinkable by using an ultraviolet light or by passing the water through an ozone generator (Miller, 2003, p. 483).

Todd, an avid observer of nature found inspiration exploring the tide pools and wetlands of his Cape Cod home. "What I learned of various ecosystems, the more I perceived their ability to self-design, self-organize, self-repair, and self-replicate" (as cited in Ausubel, 2005, p. 20). He began studying filtering species from around the world. Each plant, fish, snail, or zooplankton species provided a lesson and lent a gift to the process. Rushes are able to filter out suspended materials, other plants sequester (absorb) toxic metals such as mercury and lead, others secrete natural antibiotics to kill pathogens.

Todd's living machine's filter water for companies such as Ben and Jerry's™ and for townships such as Providence Rhode Island. They can be constructed for single buildings, such as the Environmental Science building at Oberlin College, or be made as movable "rafts" to clean up a polluted pond or lake. "Ecological machines are in many ways like ordinary machines. Like all machines they are intended to do work. But the difference between the eco-machine and the inert machine is that the living one is made up of hundreds, occasionally thousands, of species of life forms ranging from microorganisms to mollusks, and fish to higher plants, including trees. All these species work together symphonically as part of a dynamic integrated system." (John Todd as quoted in Ausubel, 2005, p. 20)Not only are these living systems cleaning waste water without using harmful chemicals, but they are living growing systems. Selling ornamental plants, trees, and baitfish which grown ecstatically in the systems help reduce the costs (Miller, 2004, p. 481).

These "constructed wetlands" can be produced in low tech manner such as those Mark Nelson is developing to treat raw sewage from hotels, restaurants and homes in developing countries where it is often otherwise dumped directly into the ocean or shallow holes (Miller, 2004, p. 506.) Natural environments can also be use if natural appropriate wetlands would already appear. Some townships are adopting constructed wetlands models, such as the one in Arcata, Ca. which won the 1987 Government Innovators Network award for construction. In the 1970's this growing coastal town found itself faced with a state mandated water treatment plan costing over fifty million dollars. Instead they decided to use the money to treat their sewage more efficiently and at the same time restore a damaged local wetland. Their "treatment pond" is now the 170 acre Arcata Marsh and Wildlife Refuge which is a popular local recreation site and attracts 80,000 visitors a year. There has been a reported increase in wildlife, especially birdlife returning to the area and both the commercial and recreational fisherman have noticed increased productivity of the local salmon fisheries (Harvard University, 2005).

From what we need to consume to what happens to our waste. In all steps of our economy and our lives we need to recognize that in spite of all our technology, including controlled climate cars, we are still part of the systems of nature. We need to look to nature to be our guide. We need to ask "what would nature do?" (Benyus, 1997) and then we need to be curious, open-minded and humble. Above all, we need to be willing to admit our mistakes and change for the better.