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UCLA Study Shows Water Reclamation Could Become An Important Source Of Future Water Supplies

October 24, 2002
University Of California - Los Angeles
Southern California's water supply is dwindling and a drought exists in the state, but the public has misperceptions and shows a lack of interest in water reuse, a potential source of water supplies, according to UCLA Institute of the Environment researchers.

Southern California's water supply is dwindling and a drought exists in the state, but the public has misperceptions and shows a lack of interest in water reuse, a potential source of water supplies, according to UCLA Institute of the Environment researchers.

The demand for water outside of California, along with environmental needs, are reducing Southern California's imported water supplies, according to a report in the institute's Southern California Environmental Report Card for 2002. Water reclamation, or the reuse of highly treated wastewaters, potentially can provide new supplies equal to approximately 50 percent of Southern California's water consumption.

"There is a lesson to be learned from the recent energy crisis," researchers Michael Stenstrom and Richard Berk wrote. "We did not construct the needed electricity-generating infrastructure or implement the necessary conservation to provide for the future. The same thing is occurring with water supply. Water-reclamation plants take just as long to construct as electricity-generating plants, and water is much less transportable than electricity."

Researchers also warned that California's drought could be more severe and longer than those in the past, and that "the problem it creates could make our electricity shortage seem trivial by comparison."

Each year, the Institute of the Environment's Report Card examines and grades the region on its progress on a range of major environmental issues. The Report Card is distributed to elected officials, environmental activists and other leaders to help guide environmental policy in Southern California.

In addition to water reclamation, this year's Report Card covers how well cities have disposed of their garbage, the protection of Southern California's biodiversity and sustainable building.

Institute researchers Stenstrom and Berk examined public attitudes toward water reclamation.

In a recent survey of Los Angeles homeowners, respondents were asked whether they would use reclaimed water for certain household and personal activities. Although the question dealt with the use of "reclaimed water at least as pure as water from the tap," respondents said they would use reclaimed water for outdoor uses but few would use it indoors.

Institute researchers noted that water-reclamation projects use advanced technologies that provide treatment well in excess of that provided for tap water. They cautioned the public against believing that water reclamation is a "toilet to tap" water program and also noted that water-reclamation programs are already taking place in California.

Stenstrom and Berk lauded the Los Angeles County Sanitation Districts for producing more than 520 million gallons per day of treated wastewater in 2000. The districts' number of reclamation sites also has increased from 100 in 1990 to 418 in 2000. They also cited the Orange County Water District for its efforts, particularly for the process known as indirect potable reclamation.

Public agencies -- particularly the Los Angeles County Sanitation Districts and the Orange County Water District -- received an "A" for showing leadership and wisely directing public investment into water reclamation.

The public received a "D" for showing a lack of interest and having misperceptions about water reclamation at a time when there is a drought and dwindling water supplies in California.

Preserving biodiversity

California is one of 25 worldwide ecological hotspots, or areas with irreplaceable plant and animal species. Yet, in the past, little has been done to preserve its unique plant and animal species, according to Philip W. Rundel, an Institute of the Environment researcher.

California's Mediterranean-climate region is so unusual that it is one of only five small regions of the world characterized by a climate of mild wet winters and dry summer conditions. This climate has led to the evolution of unique plant and animal species and habitats.

The Southern California coast is the most critically endangered area within California. Its biodiversity exists adjacent to the second-largest urban center in the United States. Los Angeles, Santa Barbara, San Diego and San Bernardino counties are four of 10 counties in the continental United States with the largest number of threatened and endangered plant and animal species.

"Threats to biodiversity in California are real," Rundel wrote. "We know of at least 21 animal species and 34 plant species that have become extinct in recent decades."

Indeed, the California grizzly bear -- the official state animal -- and the gray wolf have become extinct, and the California condor teeters on the edge of extinction.

Rundel cited various ways in which increased development negatively affects the region's plants and animals. For instance, development in the Santa Monica Mountains west of the Los Angeles basin has produced fragmentation of natural areas, including small watersheds. This habitat loss and fragmentation threatens the long-term existence of many native plants and animals, and represents the greatest threats facing biodiversity preservation. Larger mammals, such as mountain lions, bobcats and badgers, are particularly at risk.

Non-native plants and animals, or species that have been introduced by humans, also have affected California. The red-legged frog, once common throughout the state and made famous by Mark Twain in "The Celebrated Jumping Frog of Calaveras County," is now endangered because of habitat loss. Non-native bullfrogs and fish also prey on them.

Rundel highlighted the California Department of Fish and Game's Natural Community Conservation Planning. The program establishes a proactive approach in which both developers and environmentalists communicate at an early stage in the planning process. The program has been used effectively in the Southern California Coastal Sage Scrub Region to protect the threatened habitat, which is home to the rare California gnatcatcher and about 100 other potentially endangered or threatened species.

Local, state and federal agencies and developers received a "D" for their efforts over the past century to preserve habitats and biodiversity.

For the last decade, state and federal agencies, and new proactive planning processes involving both developers and environmentalists received a "C-plus."

Sustainable building

For the first time in the Southern California Environmental Report Card's five-year history, institute researcher Richard Schoen has given letter grades to various agencies for their efforts in sustainable building.

Sustainable building is development defined as "meeting the needs of the current generation without compromising the ability of future generations to meet their own needs."

Schoen noted that although cities such as Seattle, Wash.; Austin, Texas; Boulder, Colo.; and Santa Monica, Calif., have had sustainable building programs, there had not been until very recently anything close to sustainable development in the public, institutional or private sectors in Los Angeles.

The City of Los Angeles started the Sustainable Design Task Force in 1995 and in 2000, three permanent staff members were hired to carry out the Sustainable Design Implementation Program. The Integrated Waste Management Office, which has been renamed the Los Angeles Bureau of Sanitation, also successfully recycled 100 million tons of Northridge Earthquake debris. Schoen noted that the Los Angeles Community College District and the Department of City Planning also have made strides in sustainable development and construction.

The city received an "A" for its efforts in sustainable building.

Schoen also gave an "A" to the Los Angeles Department of Water and Power, Gas Company, and Southern California Edison for their various energy-conservation programs.

Village Homes, a housing development near Sylmar, received an "A" for its highly energy-efficient homes and its proximity to an Amtrak/Metrolink station. The development also received such a high grade because it was an infill construction project.

Urban parks projects received an "A-plus" for developing more park space in Los Angeles, which has fewer urban parks than any similar city in its size range in the nation. Schoen recognized the California State Parks department for its plan to develop a park and recreation complex on two former railroad yards east of downtown Los Angeles, as well as plans for a 12-acre park in Arroyo Seco in Pasadena.

Other construction projects were also cited in the report. These included the Belmont Learning Center, which received a "D" for its poor planning process and other problems, and the Playa Vista development, which received a "C" for unresolved wetland and traffic problems.

Solid waste

Southern California cities have had mixed results in their efforts to meet state-mandated trash-diversion rates, according to Ann Carlson, a UCLA law professor and a researcher with the Institute of the Environment.

The vast majority of Los Angeles County cities met a 25 percent, state-mandated trash-diversion rate as of 1995, and most also had exceeded it by 1998.

Cities received a "B-plus" for their efforts to meet the state-mandated trash-diversion rates. Carlson also noted that cities have encouraged recycling, market-based pricing for garbage pickup and other programs designed to reduce trash and reuse materials.

The grade, however, did not come without some cautionary notes.

Only 24 of Los Angeles County's 88 cities and the unincorporated portion of the county will meet 50 percent trash-diversion goals by 2000, according to the preliminary data Carlson cited in the report. Moreover, the city of Los Angeles and L.A. County's unincorporated positions are not likely to meet the 50 percent goal. Statewide, the diversion rate will equal about 42 percent.

The success in diversion rates is masked by increases in population and economic growth, Carlson said. Cities are allowed to adjust their trash-diversion rates to reflect increases for both population and economic growth. The result is that the total amount of material going into landfills has actually been rising, not falling, since 1996.

In order to increase garbage diversion rates in the future, cities must continue to implement innovative programs, which encourage the public to reuse materials and reduce the amount of garbage produced in the first place. The state must also show more leadership in waste reduction and diversion, Carlson said.

Californians will need to do a better job recycling or reducing the use of certain materials, Carlson said.

The state has already had some success in these areas. For example, the state's bottle bill, which imposes a 2.5-cent deposit on specified glass, plastic and aluminum containers to encourage recycling, has led to a recycling rate of close to 80 percent for aluminum containers and a little more than 60 percent for glass.

Extensive state regulation and research subsidies also have led to a 65 percent recycling rate for the 31 million tires Californians discard each year.

Nevertheless, a large percentage of other materials, including most plastics and food waste, wind up in landfills.

"While we've made significant progress in diverting a relatively large amount of material out of landfills, our population pressures and economic growth will require significant changes in the way we view and handle garbage if we're to continue making progress in reducing the amount of materials landfilled," Carlson wrote.

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Materials provided by University Of California - Los Angeles. Note: Content may be edited for style and length.

Cite This Page:

University Of California - Los Angeles. "UCLA Study Shows Water Reclamation Could Become An Important Source Of Future Water Supplies." ScienceDaily. ScienceDaily, 24 October 2002. <>.
University Of California - Los Angeles. (2002, October 24). UCLA Study Shows Water Reclamation Could Become An Important Source Of Future Water Supplies. ScienceDaily. Retrieved December 5, 2023 from
University Of California - Los Angeles. "UCLA Study Shows Water Reclamation Could Become An Important Source Of Future Water Supplies." ScienceDaily. (accessed December 5, 2023).

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