The Eco Machine™ at the heart of the Omega Center for Sustainable Living is the latest in nature-influenced technology designed by John Todd, a pioneer in the field of ecological design. An Eco Machine™ is a water reclamation system that cleans water by mimicking the processes of the natural world. Together, John Todd Ecological Design, Inc., Biohabitats, BNIM Architects, and The Chazen Companies designed an Eco Machine™ to address Omega's unique needs as a seasonal educational retreat center.
All the water from Omega's campus, including water used in toilets, showers, and sinks, flows to the Eco Machine™, where it is purified by microscopic algae, fungi, bacteria, plants, and snails. This natural water reclamation process cleans the water using zero chemicals. In large dispersal fields under the parking lot, the purified water is returned to the aquifer deep beneath campus.
The OCSL's Eco Machine™ treats wastewater in seven steps: 1) Solid Settlement Tanks 2) Equalization Tanks 3) Anoxic Tanks 4) Constructed Wetlands 5) Aerated Lagoons 6) Recirculating Sand Filter, and 7) Dispersal Fields. It processes up to 52,000 gallons of water per day when Omega's campus is open (May to October), and about 5,000 gallons of water per day in the off season (November to March). Each component of the Eco Machine™ at the OCSL is designed in a number of cells that allow Omega to manage the flow of wastewater. When our water usage is low, we divide the wastewater among the various cells to efficiently "feed" all the living organisms and plants that purify the water. This keeps the Eco Machine™ running well year round.
Solar energy supplies 100% of the electricity necessary to power the natural water reclamation achieved by the Eco Machine™. In addition, Omega's campus is located on the side of a hill, so gravity aids the water's flow to the Eco Machine™, reducing energy demand.
Settlement & Equalization
STEP 1: SOLID SETTLEMENT TANKS
Solid settlement tanks are the first step in the Eco Machine™ process at the Omega Center for Sustainable Living. From various tanks located throughout campus, wastewater flows into multiple solid settlement tanks. All solids settle out in the tanks as sludge and are injected with microorganisms to accelerate decomposition. The remaining wastewater flows out of the solid settlement tanks to the equalization tanks, step 2 of the Eco Machine™.
STEP 2: EQUALIZATION TANKS
All the wastewater from the solid settlement tanks flows into the equalization tanks (one of which is pictured above), the next step in the Eco Machine™ process for natural wastewater reclamation at the OCSL. Two 6,000 gallon tanks equalize the flow of water over 24 hours. This helps balance out natural surges in water use on campus (typically in the morning and early evening), evenly releasing water to the anoxic tanks, step 3 in the Eco Machine™ process.
Without the equalization tanks, the Eco Machine™, and the Omega Center for Sustainable Living, would need to have been designed and built at a much larger scale. By using equalization tanks, we were able to build the smallest facility possible, greatly reducing the carbon footprint of the Omega Center for Sustainable Living.
STEP 3: ANOXIC TANKS
Step 3 in the Eco Machine™ at the OCSL is the anoxic tanks. Two 5,000 gallon tanks are located underground, right next to the constructed wetlands at the OCSL. Here, naturally occurring microbial organisms use the wastewater stream as food. They begin to digest ammonia, phosphorus, nitrogen, potassium, and many other substances in the water. This process happens with very little oxygen (called either anaerobic or anoxic) and produces a modest amount of methane gas, though not enough to harvest and use as an energy source.
When it's time for the water to move to step 4 of the Eco Machine™ process at the Omega Center for Sustainable Living, the constructed wetlands, a splitter box evenly divides the water in half and distributes it between the upper two wetlands.
STEP 4: CONSTRUCTED WETLANDS
There are four constructed wetlands in the Eco Machine™ at the Omega Center for Sustainable Living, each the size of a basketball court. They are three feet deep, lined with rubber, and completely filled with gravel. About two inches beneath the gravel is wastewater, which flows from the anoxic tanks, to the splitter box, to the upper two constructed wetlands. The wetlands use microorganisms and native plants, including cattails and bulrushes, to reduce biochemical oxygen demand, remove odorous gases, continue the denitrification process, and harvest nutrients such as phosphorus. As the wastewater flows through the wetlands, the microorganisms and plants are fed.
Once the wastewater is processed in the upper two constructed wetlands, it flows via gravity to the bottom two constructed wetlands. In total, a lot of digestion happens in the wetlands of the Eco Machine™ at the OCSL. There is a 75 percent increase in the water's clarity and a 90 percent reduction in the water's odor by the time it is ready to leave the wetlands to move to step 5, the aerated lagoons. However, not all the water that enters the wetlands travels to the aerated lagoons. The plants absorb some of the water during the purification process in the constructed wetlands, and some of the water evaporates.
STEP 5: AERATED LAGOONS
From the constructed wetlands, the water is pumped into two highly oxygenated aerated lagoons of the Eco Machine™ at the OCSL. The aerated lagoons are divided into four cells, each 10 feet deep. At this stage, the water looks and smells clean, but it's not safe to touch. The plants, fungi, algae, snails, and other microorganisms of the aerated lagoons are busy converting ammonia into nitrates and toxins into harmless base elements.
There is no soil in the aerated lagoons at the OCSL, yet beautiful tropical plants thrive here. The plants live on metal racks and their roots extend up to five feet into the water. The roots of the plants act as a habitat for the organisms in the lagoon, and are sustained by them. The flowers of these tropical plants illustrate the beauty that naturally treated "wastewater" can yield. The blooms are abundant and are a source of flowers for Omega's classrooms.
We've learned many lessons from the aerated lagoons since we began operating the Eco Machine™ at the Omega Center for Sustainable Living in 2009. One important development was getting to know the microcommunity of bugs that needs to be in balance in the lagoons. We discovered how to identify and treat their overpopulation sustainably, so the aerated lagoons can work optimally.
Sand Filter & Dispersal
STEP 6: RECIRCULATING SAND FILTER
From the aerated lagoons of the Eco Machine™ at the OCSL, the water is sent to a recirculating sand filter. There, sand and microorganisms absorb and digest any remaining particulates and small amounts of nitrates that may still be present, and provide a final "polishing" to the water. The sand filter completes a tertiary level of water processing meeting standards for disposal into rivers, lakes, and wetlands. The effluent can also be used for irrigation.
STEP 7: DISPERSAL FIELDS
After the water has been through the recirculating sand filter, it is pumped to two dispersal fields under Omega's parking lot, each about the size of a basketball court. In the dispersal fields, the reclaimed water is released back into the groundwater table, located below the surface. The reclaimed water is further purified by nature as it trickles down to the aquifer that sits 250-300 feet beneath campus.
With this final step in the Eco Machine™ process at the Omega Center for Sustainable Living, Omega completes a closed hydrological loop in our water use. We draw water from deep wells that tap the aquifer; use the water in sinks, toilets, and showers; naturally reclaim the used water with the Eco Machine™ at OCSL; and release the purified water back to the aquifer, where the process can begin again.
The first step in designing a natural water reclamation system is to understand your existing water usage. Before an efficient design for the Omega Center for Sustainable Living was determined, a complete water conservation program was designed and put into place at Omega, including low-flow toilets and low-flow fixtures in sinks and showers. By examining water usage, not just water treatment, Omega was able to achieve the highest level of efficiency in both the construction and operation of its water reclamation system, the Eco Machine™. We also achieved the three criteria we set out for reclaiming all water used on campus: The Eco Machine™ uses net zero energy and zero chemicals to process Omega's wastewater, and it is housed in the Omega Center for Sustainable Living, an educational facility.
Omega considers water to be a precious resource. As Omega CEO Skip Backus says, "If you're calling it waste, then you've just decided to end the process in the wrong place." With the completion of the OCSL, all water on our campus is used and purified in a closed hydrological loop. Omega's water is drawn from deep wells that tap a natural aquifer. Once the water is used—in showers, sinks, and toilets—it flows to the Eco Machine™ at the OCSL, which cleans the water by mimicking nature's purification process. The purified water is then safely dispersed back to recharge the aquifer.
Within the Omega Center for Sustainable Living, our water reclamation efforts go a step further. Rainwater is collected, purified, and then used for both maintenance purposes and in the building's toilets. When the toilets are flushed, the water is then processed by the Eco Machine™.
Eco Machine FAQs
Where does Omega's water come from?
Omega's water comes from an aquifer located deep beneath campus. The aquifer is part of the Wappinger Creek watershed.
How long does it take for the Eco Machine at the Omega Center for Sustainable Living to process wastewater?
Depending on flow, it takes approximately 36 hours from the time the water is used on Omega's campus to the end of the purification process.
How many gallons of water does Omega's Eco Machine process each day?
Omega is an educational retreat center that runs seasonally from April through October. In the off-season, our Eco Machine processes approximately 5,000 gallons of wastewater per day. On an average day during the season, it processes about 25,000 gallons. The Eco Machine is designed and licensed to process up to 52,000 gallons of water per day.
How do solids get processed in the Eco Machine at the Omega Center for Sustainable Living?
Organic solids, as well as a number of man-made products that get flushed down the toilets, go to solid settlement tanks. All solids settle out as sludge and are injected with mircroorganisms to accelerate decomposition. Undigested sludge is pumped out by a licensed facility.
How does the Eco Machine adjust to fluctuating use?
The Eco Machine at the Omega Center for Sustainable Living was specifically designed with numerous individual cells that allow us to control the flow of wastewater. In this way, we can "feed" the microorganisms of the Eco Machine evenly no matter how much water is being processed on a particular day. In addition, the circulation of water can be controlled to increase or decrease through the Eco Machine as demand changes.
Once the water is treated by the Eco Machine, where does it go?
The water purified by the Eco Machine is released back to the aquifer beneath our campus in two large dispersal fields under Omega's parking lot. This final step completes a hydrological loop: we draw our water from the aquifer, use it, purify it, and return it to the aquifer again.
How does the Eco Machine work in winter? Does it freeze?
The Eco Machine works well year round. Even during the coldest winter months, the microorganisms within the Eco Machine produce enough heat to keep the water from freezing. Also, the plants in the wetlands and the green roof are perennials that go dormant each winter and being to grow again in the spring.