The living machine or Eco machine is a wastewater treatment system that naturally treats sewage and industrial waste to re-use quality. An important consideration as fresh water becomes one of the most important commodities in the new millennium. The initial development of living machines is generally credited to John Todd, and fall within the emerging discipline of ecological engineering, and many similar systems are built in Europe.”

How does it work?

ECO Machines accelerate nature's own water purification process. Unlike chemical-based systems, ECO Machines incorporate helpful bacteria, fungi, plants, snails, clams, and fish that thrive by breaking down and digesting organic pollutants, pollutants that normally deprive the water of oxygen. This clean, simple approach efficiently transforms high-strength industrial wastewater and sewage into water clean enough to be recycled for reuse.

The scale of living machines ranges from the backyard experiment to dependable public works. Some living machines treat domestic wastewater in small, ecologically-conscious villages, , and some treat the mixed municipal wastewater for semi-urban areas

Each system is designed to handle a certain volume of water per day, but the system is also tailored for the qualities of the specific influent. For example, if the influent contains high levels of heavy metals, the living machine must be designed to include the proper biota to accumulate the metals

for more information
http://www.toddecological.com/ecomachines.html

http://en.wikipedia.org/wiki/Living_machines