Benefits
- Up to 7,000 gallons of wastewater treated daily.
- Plenty of clean recycled water available for drip irrigation, reducing water use.
- Much lower energy use and greenhouse gas emissions than conventional treatment systems.
- Designed for scalability; will be sized up as Esalen develops its recycling practices.
- Native wetland plants fit beautifully into the local landscape.
- Mission Accomplished: Educate people about sustainable ways of living.
The northern California coastline is a national treasure. The Esalen Institute, founded in 1962 presides over their 27 acres of it with pride and a fierce sense of conviction. As an alternative education institute, with nearly a half century history of focus on human potential and living in the world with wisdom, Esalen lives its convictions more than most of us do.
So when Esalen set out to upgrade their existing facilities, they wanted to make sure they could also make a statement about how we should treat our precious resources.
A little background: Northern California has a problem. Aging systems, and thousands of miles of old pipes built out of clay, have made the San Francisco Bay area one of the wastewater spill capitals of the world (over 10 million gallons of untreated or partially treated waste in several recent spills alone). It's understandable, then, that Esalen wanted to provide a good example to their neighbors.
The Tidal Wetland Living Machine® at Esalen takes wastewater from the institute's laundry and lodging facilities and turns it in to clean water. The cleansed water then gets reused for irrigation of the extensive gardens and returned directly to the re-charge the aquifer.
How does that fit with the institute's mission? The Initiatives page of their website says it best:
Esalen's sustainable wastewater recycling model will conserve fresh water, protect Esalen's fragile cliff shelf along 26 miles of prime Pacific coastline, protect the Big Sur bioregion, save energy, promote sustainable economy, and provide a model of green technology for California's educational & business communities and for Esalen's 17,000+ visitors per year.
The Esalen Institute’s Tidal Flow Wetland Living Machine® uses Worrell Water Technologies’ proprietary next generation wetland design, mimicking the flow of tides to safely cleanse wastewater. The tidal flow brings an abundant supply of oxygen to the beneficial organisms that do the primary work of cleaning the water, with a much lower cost in energy than using a mechanical aerator.
Wastewater from the Institute’s existing sewer line and laundry facility enters the Living Machine from a 10,000 gallon settling tank. The tank has two compartments where solids are allowed to settle out and the flow of water through the system is equalized.
After the tank, the wastewater enters the first of six custom designed tidal wetland basins. The basins are connected by subsurface plumbing, and contain a gravel aggregate topped with plantings of a variety of indigenous wetlands plants. The gravel media supports the plants’ root structure and creates a thriving ecosystem for the engineered films of microorganisms that consume pollutants in the water.
The basins are successively filled and drained in several cycles daily as the water is moved through the wetlands basins. It emerges to a final stage where it is disinfected and then stored in an underground storage tank. The naturally cleansed water is then reused to irrigate a 2,250 square foot garden. What isn’t used is put back into the ground, where it can re-charge the local aquifer.
Esalen’s Living Machine is built to grow. As they build their wastewater recycling program, their Living Machine is designed to be readily scaled up to handle more water and put it to use in larger irrigation projects.