Rohnert Park company working on more efficient and earth-friendly ways to get the salt out of sea water

Trevi Systems is seeking environmentally-friendly and cheaper ways of turning sea water into fresh water.|

Trevi Systems at-a-glance

Founded: 2010

Officers: John Webley CEO, Michael Greene, Vice President of Engineering

Headquarters: SOMO Village, Rohnert Park

Employees: 13 in Sonoma County, 1 in Japan, 1 in France

Product: Environmentally friendly desalination


Editor’s Note: The Press Democrat is publishing a series of stories about Sonoma County innovators who are tackling global warming. We invite readers to propose stories of those involved locally in climate change. Share your ideas by contacting our editor,

As the current drought stretches into its third year, demands to desalinate ocean water rise, especially in such places as Sonoma County and its more than 55 miles of coastline.

But putting a desalination plant on the Sonoma County coast seems unlikely, especially after the California Coastal Commission in May rejected construction of a desalination plant in Huntington Beach that had been studied for more than 15 years, said entrepreneur John Webley.

He should know. As CEO of Trevi Systems in Rohnert Park, he’s been experimenting with desalination for 12 years. He says the journey, though hard, has been worthwhile, especially now.

"I'm a hands-on engineer. I like to fix things that are broken. I thought, let's go do something about this,” said Webley during a recent interview at Trevi’s SOMO Village headquarters. “There wasn’t such a mandate when we started, but now I believe the drive to make renewable water treatment is here to stay.”

Trevi Systems, named after the Trevi Fountain in Rome, is primarily trying to solve two problems.

One problem is energy. Today’s dominant desalination methods use large amounts of energy, mostly from fossil fuels with significant CO2 emissions.

Number two is waste. These desalination methods leave behind a large volume of high-salinity water, or brine, that must be deposited somewhere, often back into the ocean.

These issues make desalination expensive for customers and taboo for environmentalists.

Trevi Systems has experimental work underway in both areas.

In June, Webley was in Kailua-Kona, Hawaii, for the commissioning of a pilot desalination plant fueled 24/7 by the sun. When the sun isn’t shining, the operation is powered by heat captured from a solar plant and stored in water tanks.

Meanwhile, at the lab in Rohnert Park Trevi chemists and engineers believe they’re closing in on a process that could nearly eliminate the brine.

These projects are fourth- and fifth-generation versions of the work Trevi Systems has been doing for more than a decade. Along the way, they’ve spotted a possible new customer: agriculture.

Drought-wary agriculture is searching for new sources of water, especially since 2014 when the California legislature passed the Sustainable Groundwater Management Act that began regulating groundwater for the first time.

Since agriculture uses about 80% of California’s water, according to the state Department of Water Resources, new water for farmers could free up other water for public use, Webley said.

“That’s what I’m trying to solve now,” he said.

To vastly oversimplify, desalination is a way to make clean water out of seawater or waste water by using osmosis, which moves liquid through a semipermeable membrane or filter.

Most desalination plants use reverse osmosis, where salt water is forced through a filter that lets fresh water through and leaves a salty, watery brine behind. The process consumes a lot of energy, and the remaining brine must be discarded.

Trevi Systems and others are trying forward osmosis, where a concentrated solution draws fresh water across the membrane, requiring less electrical energy. Going two steps further, Trevi’s team is using solar heat for power, not fossil fuels, and they’re refining the process to try to eliminate the brine.

Trevi has tested desalination systems in Port Hueneme, Kuwait, Abu Dhabi, Orange County, Saudi Arabia, Cyprus, Oman and Hawaii, each time learning and refining, Webley said.

Trevi is a small player in an industry that has roughly 20,000 desalination operations worldwide, including 12 in California, many built by global giants.

Trevi assembles its systems in Rohnert Park, with parts it brings in from around the world, and it ships assembled components to plant sites.

None of the Trevi plants produce water for people to drink. For example, water produced by the Cyprus plant goes to a research facility to water its campus, and in Oman, the water goes to oil and gas companies for industrial use.

In Hawaii the water will go to Cyanotech, a Kailua-Kona company that makes health and nutrition products like Spirulina from microalgae, which it will irrigate with desalinated water.

“Cost, along with less tangible environmental benefits, will define the viability for this technology here and elsewhere,” said Gregory Barbour in a recent email, speaking for the state agency that heads the project.

Meanwhile, back in Rohnert Park Trevi is working on the high-salinity brine, with potential agriculture customers in the wings.

“I met John through the National Alliance for Water Innovation, and I told him what I wanted to do,” said Clark Easter, CEO of Global Water Innovations in Cambria. “He disappeared for about a year, and then he called and said, ‘I think I have a solution.’”

Easter wants to use desalination to treat brackish groundwater and create new supplies of water for California agriculture, but the salty brine that traditional technologies leave behind is costly to discard and wastes water.

Trevi is working with Easter, Idaho National Laboratory and others, with some grant funding from the U.S. Department of Energy, to try to treat that brine and leave behind only slightly moist salts that farmers could take to a landfill or even tap for minerals to recycle to manufacturers.

Easter said he has seen Trevi’s process in action and it is “compelling and a game changer.” Now the trick, Webley said, is to build a plant to do it in the real world.

“It’s quite the challenge, but I get ag inquiries every day. Ag could be a major business for us,” Webley said.

Trevi’s early-stage financing has come mainly from family, friends and local investors.

“If not for this community, we wouldn’t be in business,” Webley said.

The company is not yet profitable. Webley said revenue is “several million dollars a year” not counting nine grants. A recent $10 million investment, led by two Japanese companies that supply key components for the Trevi desalination process, is enabling Trevi to grow its business, Webley told the Water Desalination Report journal in November.

Webley, 64, cofounded two prominent telecommunications companies in Petaluma, Advanced Fibre Communications in 1992 and Turin Networks in 1999.

In 2010 Sonoma County scientists Gary Carmignani and Steve Sitkiewitz brought osmosis ideas to Webley's Innovative Labs, a technology incubator he founded to give help and seed money to people working on thorny problems “because it’s fun,” he said.

Webley saw potential and he and the scientists started Trevi Systems with Webley as CEO and Carmignani as chief science officer. Carmignani has since retired.

“It’s a lot harder to innovate in this field than in telecom, but the payoff for society is much bigger,” Webley said.

Mary Fricker is a retired Press Democrat business reporter. She lives near Graton. Reach her at

Trevi Systems at-a-glance

Founded: 2010

Officers: John Webley CEO, Michael Greene, Vice President of Engineering

Headquarters: SOMO Village, Rohnert Park

Employees: 13 in Sonoma County, 1 in Japan, 1 in France

Product: Environmentally friendly desalination


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