Purification system that makes toilet water clean enough to drink is closer to coming to San Diego

SAN DIEGO - The San Diego City Council's Natural Resources and Culture Committee asked city staff Wednesday to begin planning for a system to recycle used water into drinking water, and report back in three months.

The panel's action comes after a one-year "indirect potable reuse" pilot project found that the product that would go into the city's water supply would be of higher quality than what is currently available. The data was derived from 9,000 laboratory tests.

Staff will look into two concepts -- an indirect method in which water is purified and delivered by pipeline into the San Vicente Reservoir, and an alternative that would send converted water directly into city pipes.

Legislation is being circulated in Sacramento that would allow for the direct route, which would cost the city far less money since the 22-mile pipeline wouldn't have to be built.

Since the proposed state bills are new, most of the planning for what used to be criticized as "toilet-to-tap" has focused on an indirect system.

"The general public I think has recognized that indirect potable reuse is now something that is not only possible but is the right way to go," committee Chairman David Alvarez told reporters. He said polling shows nearly two-thirds of San Diegans opposed IPR nine years ago, but now about three-quarters support the idea.

According to Marsi Steirer of the Public Utilities Department, the $369 million IPR system would take used water, send it through a three-stage cleansing process -- filtration, reverse osmosis, and ultraviolet light and oxidation treatment -- and deliver it to be mixed with reservoir water.

It would then go through the city's standard treatment process for drinking water before delivery to customer faucets, Steirer said.

Thousands of people in Orange County have been drinking and bathing in exactly this kind of recycled water since 2008. Tests show it comes out more pure than standard tap water.

Some San Diegans, when asked if they would drink this type of purified water, did not jump at the prospect.

"You know, I don't… I don't know for sure if I would or not," said Sarah Zimmerman, who lives in North Park.

Mission Hills resident Adam Strohl said, "If the purification process is legitimate and works, I think it's something to look into."

San Diego Mayor Bob Filner would not talk about getting people over the "toilet to tap" concept. Instead, he called it something else: "Showers to flowers."

The city says its study shows more than 70 percent of San Diegans support it. However, according to a scientific 10News poll, only 39 percent of San Diegans say they support the "toilet to tap" concept while 51 percent said they oppose it.

Supporters say the resulting augmentation of the water supply would reduce San Diego's dependence on imported water, which they expect to increase in cost by 6 percent annually.

"The successful implementation of advanced water purification can help save taxpayers $1 billion in improvements that are currently needed out at Point Loma," said San Diego City Councilman Todd Gloria.

Exploring IPR is part of City Council policy to have "an affordable, reliable, energy-efficient and environmentally safe water supply for San Diegans," Councilwoman Lorie Zapf said.

Steirer said that once financing for the indirect system is arranged, it would take eight to 10 years to put into operation -- with most of the time consumed by pipeline construction. If a direct system is authorized by the state, a water recycling program could be put into effect faster, she said.

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