Turning gray water green

Article published on ISRAEL21c July 21, 2011

By Karin Kloosterman

A simple Israeli system for collecting, treating and reusing household water arrives right on time for global water shortages.

The facts on the ground are stark: Israel is in a serious water deficit. The Sea of Galilee is shrinking every year, as are its underground aquifers. Yet water needs are increasing along with energy costs.

One answer to this crisis may be found in the water we send down the sink and bathtub drains. Much of this "gray water" can be lightly treated and reused to flush toilets and water gardens.

Putting that ideal into action on a large scale is the target for Gil Ben-Meir, inventor of the Evergreen gray water solution developed by his company, Green Solutions. Some 150 family Israeli homes have already installed Evergreen. This business owner, working since 2009 on the project, is intent on making a dent in the foreign market with Israel's already well-known water solutions that work.

Water levels in the Sea of Galilee are dropping dramatically year by year.

Speaking at the 15th annual Cleantech Exhibition in Tel Aviv in July, he tells ISRAEL21c that the Evergreen system is a small, affordable and easy-to-maintain gray-water processing device that can treat up to 600 liters of household water a day, or about 150 gallons.

Fitted to every pipe but the kitchen sink and toilet - wastewater from these drains contains too much organic material and oil to be safely recycled -- the system collects gray water from baths, showers, hand-washing basins and washing machines. Running through a specially developed biofilter, the treated gray water is then sent to the toilet and to the garden, where it can be reused instantly.

The system may be just the solution needed in chronically dry areas, including the Greek Isles, other Middle Eastern countries and American states like California and Nevada.

Rinse and repeat

The average household in America consumes about 350 gallons of water per day, according to the website drinktap.org. About one third of that could be salvaged, treated and reused with this new Evergreen system.

It's easy to install, the filters are self-cleaning and the maintenance is simple - "once every three or four months," says Ben-Meir. "Everything one needs to operate it is supplied with the system."

With the average cost for parts and installation about $4,000, or NIS 15,000, the return on investment is about five years, and the system runs on the same amount of electricity as it takes to burn a 70-watt bulb all day. Evergreen can be scaled up for apartment complexes and other higher demand locations.

Quieter than an air conditioner, Evergreen measures about 180 by 70 centimeters (71 by 27.5 inches) -- much smaller than similar solutions, says Ben-Meir. "The innovation here is its adaptation to smaller applications with a small footprint. What usually takes three to four square meters of space is now contained in less than two square meters, at a 50 percent cost reduction."

He assumes the tool would also work in cold climates like Canada and northern Europe, since the system can be installed in a basement and operates on the temperature of the water fed into the system.

Evergreen can be fitted with a holding tank to process water and store it for use during peak hours and days.

Energized by Israel's challenges

Ben-Meir founded Green Solutions after living in the United States for 13 years and studying energy management at the New York Institute of Technology.

"I came back from a long stay in the States, where I was doing something completely different, and in 2005 I decided to switch to the environment field -- to the clean-tech sector," says Ben-Meir. "I completed a master's degree and decided to come back to Israel and to work on solutions for gray water."

At that time, Israel was at the start of five years of drought. "There was a serious shortage of fresh water, and I was looking for ways to recycle and save water. Here is the fruitful soil to grow on and develop it," he adds, referring to Israeli expertise in water reclamation.

Based in Zichron Yaakov, Green Solutions currently employs three people, and also provides solar energy solutions for homeowners.