Thursday, May 15, 2008

IN FACE OF WATER SHORTAGES, TOILET TO TAP RECYCLING PLANS GROW

LA TIMES Los Angeles officials will revive a controversial proposal to recycle wastewater as part of a plan to curb usage and move the city toward greater water independence. . . Mayor Antonio Villaraigosa's effort could cost up to $2 billion and affect a wide range of daily activities. For example, residents would be urged to change their clothes' washers, and new restrictions would be placed on how and when they could water lawns and clean cars. . . . Builders would be pushed to install waterless urinals, weather-sensitive sprinkler systems and porous parking lot paving that allows rain to percolate into groundwater supplies.

Prohibitions during the 1990s drought -- banning residents from washing driveways and sidewalks, letting sprinklers flood into gutters and watering grass in midday -- would be enforced again, with additional restrictions. One part of the proposal would limit lawn watering to certain days of the week.

Cities facing the same challenges, including Long Beach, have already moved to curtail residential and commercial water usage and punish waste. . . .

Los Angeles' plan -- a copy of which was made available to The Times -- would invest in projects to capture and store rainfall and clean up a sprawling, contaminated water supply beneath the San Fernando Valley. About $1 billion would be allocated for reclamation, including a politically sensitive plan to use treated wastewater to recharge underground drinking supplies serving the Valley, Los Feliz and the Eastside.

A similar system was approved and built in the 1990s, then abandoned after critics labeled it a "toilet-to-tap" scheme. . .

One critic said voters should decide whether the water supply will be blended with treated wastewater. "It's grossly unfair for the mayor, the City Council or the DWP to decide consumers are going to be using this recycled water," said Gerald A. Silver, president of Homeowners of Encino.

But Millie Hamilton, an Encino Neighborhood Council member and docent at the city's Tillman Water Reclamation Plant, said recycling is safe, needed and nothing new. "There is no new water on this planet," said Hamilton, who was referred to The Times by the mayor's office. "We are drinking the same water the dinosaurs drank. All our water has been and is being recycled."

WALL STREET JOURNAL
Cities ranging from San Diego to Denver already recycle wastewater for irrigation and industrial use. Some communities, such as the Tampa Bay area of Florida, desalinate seawater, which is generally more expensive than recycling. Many cities are also pushing water-conservation initiatives such as implementing restrictions on when residents can water lawns or offering rebates for high-efficiency washers and toilets.

But cities considering large-scale systems that recycle wastewater to drinking standards may face an uphill battle. Such initiatives -- dubbed "toilet to tap" proposals by critics -- have encountered resistance in the past as a result of cost and the overall yuck factor. In 2001, Los Angeles scrapped a $55 million wastewater-recycling project that would have provided the equivalent of the annual water needs of 200,000 city residents. A similar proposal in San Diego was derailed in the late 1990s amid an outcry that poor neighborhoods would be forced to use the wastewater from rich neighborhoods.. . .

The concept of recycling wastewater to meet drinking-water standards isn't new. A handful of cities in the U.S. and abroad have done it on smaller scales and sometimes with older technology. In most cases, the water is disinfected and pumped into an aquifer or reservoir where it remains for a period of time before being distributed to the public through drinking-water wells -- a concept known as indirect potable reuse. Wastewater in Orange County is treated with reverse osmosis to remove viruses, salts and pharmaceuticals.

Recurring droughts and growing populations are increasing the allure of recycling. In Los Angeles, groundwater contamination in the San Fernando Valley, where the majority of the city's groundwater supply is produced, has limited water available for pumping. "If we don't commit ourselves to conserving and recycling water, we will tap ourselves out," says Los Angeles Mayor Antonio Villaraigosa in a statement.

A new system in Orange County, Calif., where water demand is expected to increase 16% between 2010 and 2030, is the largest and most high-tech in the world. . . Other cities that are planning their own projects say they are using the Orange County system as a standard.

It is a three-step process: Sewer water that has already been treated by the county's sanitation district goes through a microfilter to remove solids and bacteria. It then undergoes a reverse-osmosis treatment, which passes the water through a membrane filter that removes viruses, salts, pharmaceuticals and other materials. Finally, it is treated with ultraviolet light and hydrogen peroxide to get rid of contaminants that are left.

The water is then pumped into a groundwater basin where it mixes with other water and filters through materials like sand, gravel, and clay. It takes about a year for the water to travel to a drinking-water well -- so county residents aren't yet drinking water that has been treated with the new system. The Orange County Water District, which manages the county's groundwater basin, compares its quality to that of distilled water.

Parts of Orange County, though, have been drinking treated wastewater since the 1970s through a system called Water Factory 21, which used reverse osmosis on a smaller scale. That system, when it existed, recycled just five million gallons a day.

Doctors and engineers say recycled water is safe to drink. Indeed, reverse osmosis coupled with ultraviolet light and hydrogen peroxide treats wastewater beyond what federal and state drinking standards require, they say.