It’s said that business ideas often come to people in the shower. For Santa Monica resident and former visual effects tinkerer Garry Sato, his new business idea didn’t just come to him in the shower, it was about the shower itself.

He wondered: Instead of allowing the water to flow down the drain, into the sewer system and out into the ocean, why not divert the water into a separate set of pipes and reuse it to water his garden?

Reusing shower, sink or washing machine water is nothing new, of course. It even has a name: greywater. But to reuse the water, a homeowner must either capture it in buckets or go outside the house and turn a valve.

Sato’s shower inspiration five years ago was to develop a diverter valve and a companion remote control; so equipped, a homeowner can instantly switch from sending greywater into the sewer to diverting it into a reusable water system.

“The idea is that with just the pressing of a button, you can be generating greywater,” Sato said.

Sato, 65, is now on the verge of bringing his greywater diverter to market, with an expected final deal with a major national plumbing supply retailer set to close within weeks.

Niche market

But Sato also faces a tough challenge. His diverter would only be one component in a larger greywater piping system both indoors and outdoors. So, only homeowners willing to spend a few thousand dollars up front for such a system are likely to have their plumbing contractors buy the diverter. That might not be enough demand to turn Sato’s product into a moneymaker.

“Right now, the market size is not defined for this diverter,” he said. “So we’re focused on defining that market.”

That was not uppermost in Sato’s mind while he spent three years developing the prototype diverter in his garage, using skills he acquired from his days as a motion picture visual effects supervisor, where many of his effects used water that had to be piped in. He then sought and received the first-ever plumbing industry certification for a diverter specifically for greywater. All this cost him about $200,000 of his own money.

The diverter contains a valve and pipes that branch out in a Y shape; the valve allows water draining from a shower or washing machine to switch from a pipe connecting to the sewer to a pipe for water to be reused outside the house.

The reason for the valve and dual pipes: Not all water in a home can be reused. Toilet water is completely off limits. But it also violates health codes to reuse water from a washing machine load containing soiled diapers; that used water must go directly to the sewer to be treated.

Until now, the market for greywater among homeowners has been tiny, confined mainly to Ed Begley Jr. types who devote their lives to rigorous conservation goals or to very small-scale use, such as taking a couple of buckets of shower water outside for use on plants.

Sato has installed the system in his home and said he saves about 100 gallons a day as a result. Now, he’s hoping the drought will drive his product into the mainstream. The idea: When residents face stiff financial penalties from water agencies for exceeding their allotment of water – the city of Los Angeles is even considering even shutting off water in egregious cases of overuse – reusing more of their water will make economic sense. Sato’s diverter would allow homeowners to reuse a larger share of water than possible with buckets and would be more convenient than an external valve.

Sato is close to finalizing a deal to supply five Santa Monica-area stores of Newport News, Va., plumbing parts giant Ferguson with his greywater diverter. The valve is expected to retail for a few hundred dollars.

Ferguson spokeswoman Christine Dwyer confirmed the chain is placing the order for the diverters and that they will soon be on store shelves. Sato has made roughly 200 diverters himself; he and Ferguson are both talking with a contract manufacturer to ramp up production.

“We’re excited to see how the product does locally,” Dwyer said last week.

But industry analysts and officials at cities developing greywater policies say Sato’s diverter is likely to face a tough time gaining traction among homeowners. That’s because the diverter can only be effective if it’s part of a much larger – and costly – greywater plumbing system, both inside and outside a home.

First, as even Sato admits, additional piping is needed inside a home to accommodate his greywater diverter. Depending on the age of existing pipes and the amount of new piping needed, that cost alone could be more than $1,000, especially in homes built on concrete slabs that have to be pierced in order to install new pipes.

Once outside, local plumbing and health codes require the water to remain at least two inches underground. The codes ban the dispersion of greywater above ground – either with a hose or existing sprinkler system – because of the risk of spreading bacteria in what’s essentially untreated wastewater. So another extensive plumbing system is required, and that in turn requires a municipal construction permit.

“You’re talking about a perforated piping system or drip irrigation system, which requires a pump and a timing device in addition to all that piping,” said Ed Saltzberg, a Van Nuys forensic plumbing consultant who frequently testifies as an expert witness.

Costs mount even further if a homeowner plans to store the greywater until enough accumulates to give outdoor plants a good soaking. The stored water must be passed through a filter first.

As a result, more complex greywater systems can cost more than $10,000, which must all be spent before the first drop of water can be reused.

What all this means is that Sato’s greywater diversion device alone is unlikely to convince existing homeowners to turn to greywater use. Rather, it’s part of a much larger financial commitment to use greywater; an up-front investment of thousands of dollars that could take years to recoup, even factoring in drought-related financial penalties for water use.

“The diverter is just a single component in a much larger system,” said Craig George, environmental sustainability department manager for Malibu, which has developed greywater regulations. “It’s an important part of a system, but only a part. You can’t just install one of Garry’s diverters and be ready to move over to greywater.”

New construction

Given this huge outlay, both George and Saltzberg said Sato’s device is best suited as a plumbing component in newly built homes. That way, a homeowner would face additional costs mainly for only the outside piping system.

“This is best done up front in new construction,” Saltzberg said. “That’s where the real use for (Sato’s) device would come in, as one of the components that a plumbing contractor on a development project would use.”

Sato agreed, saying that’s why he’s trying to convince state officials to enact a mandate that all new residential construction contain dual piping for greywater systems. He hopes this mandate can be included in the next overhaul of the state’s building code, due out in three years – or even sooner if possible.

George said Malibu has a requirement that dual plumbing for greywater be included in new development projects where feasible.

“It gives the owner the capability to divert greywater outside the building if they so wish,” he said.