UCLA works to conserve, not consume
By Heidi Redlitz
Feb. 2, 2010 11:04 p.m.
From its five swimming pools to its massive medical center and 419-acre campus, UCLA consumes 2.4 millions gallons of water per day, totalling an expense of $6 million a year, said Tova Lelah, assistant director of Campus and Environmental Planning.
To alleviate the high economic and environmental costs of water consumption, UCLA is conducting ongoing research and construction projects to direct alternative sources of water to facilities requiring high volumes of water.
“Recovered water is kind of an umbrella term. Instead of going down the drain, it’s recovered and reclaimed and reused,” Lelah said. “The (Los Angeles Department of Water and Power) water supply chain has shrunk. In the future, we’re going to have static or reduced supply, and the only way we can make it up is if we use (recovered water).”
Lelah heads the Water Task Force, part of UCLA Sustainability, which researches methods to reduce water consumption and to promote sources of water reuse.
The cooling towers of the university’s co-generation plant stand as the largest source of water consumption at UCLA, claiming 24 percent of UCLA’s total water expenditure, Lelah said.
“The amount of water consumed in that process can be as high as 400 gallons per minute. Most of the time, it’s significantly lower; it probably averages 200 gallons a minute,” said Dave Johnson, UCLA’s director of energy services and utilities in Facilities Management. “During (winter)time, the number is probably 50 gallons, so it varies significantly.”
Incoming heat from the campus’s buildings is diverted to the constantly running cooling towers so that on a hot, high-humidity day, water evaporates from the towers to provide cooling. There are 11 towers on the roof of the power plant to cool at least 40 campus buildings, Johnson said.
One cost-effective method of water reuse is the circulation of recovered water from natural sources, like the groundwater surrounding Ronald Reagan UCLA Medical Center’s deep foundations, to the Co-gen cooling towers.
The recovered water supplies 70,000 gallons daily, said Johnson, which translates to nearly $100,000 in annual savings on water expenses.
The water condensate air conditioning system is another sustainable process that brings chilled water from cooling tanks, like that at Co-gen, to campus buildings that run as far north as Murphy and Melnitz halls, Johnson said.
All buildings have an internal air distribution system, with fans drawing air from the outside into heating and cooling coils of each building. When air passes through the cooling coil, the resulting condensate from the temperature difference between the warm air and cool pipes is collected into an alternate pipe and circulated back to the cooling towers, said Johnson.
“Water is not consumed in the process. It’s almost like a truck that’s carrying cooling some place, but in this case it’s a liquid,” Johnson said.
This method reduces the amount of water needed from the LADWP by about half, Johnson said.
While the condensate recovery system and groundwater recovery system from the medical center serve as functioning examples of reuse, the task force has many projects on its wish list.
One project in the works is a proposal to install artificial turf onto the Intramural Field, an expanse of grass that requires 3.9 million gallons of water a year, said Richard Ohara, senior grounds superintendent for UCLA Facilities Management.
The field’s high water consumption is a result of its sand basin, used as a method of water dispersal to alleviate ceiling pressure on the parking garage beneath the field. If the field had instead been constructed with the proper 18 inches of topsoil designated for a field its size, the amount of water absorbed by the soil would have created too heavy and unstable a ceiling above the parking lot, Ohara said.
“I’m basically watering sand. That water goes down into our storm-water system. None of the landscaping water gets recycled yet,” Ohara said.
But attempting to reclaim used irrigation water rather than sending it to the storm drain is a long-term investment still some years away, Lelah said. Greater efficiency systems cost money, a commodity almost as scarce as the water it funds. So improvement projects are done in phases that accord to budget allocations for irrigation-related expenditures. One initial phase is to retrofit new sprinkler heads to the old, less-efficient heads of the 1960s and 1970s. The new heads would use only two gallons per minute, despite any changing pressure in the pipes pumped by the LADWP, Ohara said.
Drip irrigation is a new technology also utilized for campus. A series of underground pipes drip water adjacent to the plant, eliminating excess water dispersal and runoff on the ground’s surface.
“With the drip system, instead of gallons per minute, we do gallons per hour now,” Ohara said.
Despite budgetary limitations, UCLA’s various operations departments are promoting water-saving efforts for both economic and sustainable incentives. Yet looking to the future of lessened consumption also invites a retrospective view of water use. Lelah has compiled water consumption data back to 1979.
“Over that period we have reduced water consumption almost 30 percent, and we have added millions of (square feet) for new buildings. And buildings consume more water than irrigation,” Lelah said. “It’s still a lot (of water). There are 200 buildings and 60,000 people on campus every day.”
