Wednesday, Dec. 17, 2008 | Last year, almost 1 percent of the city of San Diego’s drinking water supply — 635 million gallons — got sprayed on freeway shoulders to keep plants green.
The water was pumped hundreds of miles from Northern California and the Colorado River, pushed through a vast system of pumps and aqueducts and treated to be safe for human consumption. Then CalTrans bought it from the city for $2.2 million and sprinkled it on medians and shoulders to accomplish what, in this semi-arid region, Mother Nature couldn’t.
CalTrans says it uses the water to irrigate plants that beautify highways, block views into private homes, create buffers in medians, control erosion and provide fire protection. Many of the plants are drought-tolerant, requiring less water than others, but they would not survive without irrigation.
The transportation agency doesn’t use the water it buys as efficiently as it could. The agency doesn’t have smart irrigation controls on 75 percent of its roadside sprinklers. Those would allow one person to turn sprinklers on or off with the touch of a button on a central computer.
Instead, many sprinklers are manually programmed to water three times a week in summer, twice a week in spring and fall and once a week in winter. Because they’re not easily adjustable, the sprinklers can operate even during rainstorms unless CalTrans staff shut them off, one-by-one. The agency sends its workers to turn them off when more than one-quarter of an inch of rain is forecast, said Hayden Manning, a CalTrans spokesman.
As the region’s water supply gets restricted, attention is increasingly turning to CalTrans’ use of drinking water for maintaining roadside landscaping. The region’s two major supplies are crimped by drought and endangered species protections. Water agencies say residents must save water by reducing outdoor irrigation. And few in the region pour more water on plants than CalTrans. It’s the city of San Diego’s fourth-largest user; it’s the top user in the Helix Water District, which serves La Mesa.
CalTrans hasn’t made more upgrades to reclaimed water for the same reason that many large water users haven’t: Water is cheap. Water-efficiency upgrades aren’t.
The city of San Diego charges commercial customers $.003 for each gallon — less than a cent. Even those users with the highest bills say they have little financial incentive to make water-efficiency upgrades. They don’t pencil out for more than a decade. While the city gives residential customers a financial incentive to use less water, it doesn’t do that for businesses. For them, the first gallon costs as much as the millionth.
Large agencies acknowledge that water is precious and that conserving it is the right thing to do. But they also say many upgrades do not provide a fast enough return on investment to be justified solely on their monetary savings.
“It’s kind of a Catch-22,” said Manning, the CalTrans spokesman. “We want to be good stewards of the taxpayer’s dollars. We also want to be good stewards of the taxpayer’s water.”
Water agencies are looking for ways to get CalTrans and other large consumers to use less drinking water. One local agency plans to do that by changing its rate structure to provide financial motivation. The city of San Diego questions whether CalTrans should continue building landscapes that need water at all.
The San Diego County Water Authority, the wholesaler that supplies all local water agencies, will also consider this week whether to lobby for statewide legislation to require CalTrans to use reclaimed water for irrigation — a requirement already in place for other state agencies. Reclaimed water is highly treated sewage that’s not clean enough for human consumption.
CalTrans currently uses drinking water in most of its landscaping in San Diego County. About 2,730 of the 3,300 acres CalTrans irrigates use drinking water.
“This is attempting to close a loophole to bring CalTrans into the fold of state agencies required to get off potable and on to recycled,” said Dennis Cushman, the water authority’s assistant general manager. “Where reclaimed water is available for use for a user such as CalTrans, to use potable water is clearly not the best use of that resource.”
Mayor Jerry Sanders and other regional officials have spent the last 18 months calling for users to voluntarily cut water consumption 10 percent. CalTrans didn’t meet that goal. It cut consumption 3 percent from July 2007-June 2008 compared to a year earlier. If CalTrans had cut its use by the recommended amount, it would have saved as much water as 5,000 single-family homes making the same effort.
Prioritizing water-efficiency upgrades in the CalTrans budget comes down to a “question of resources,” said Ted Thurston, CalTrans water manager. A system-wide upgrade to centrally controlled sprinklers would cost millions.
“Water doesn’t cost that much, frankly,” Thurston said. “It takes a lot of savings” for conservation to pencil out financially.
Alex Ruiz, assistant director of the city of San Diego Water Department, questioned why CalTrans doesn’t eliminate plants in its new construction projects as it has in parts of the South Bay. CalTrans used decorative rock for landscaping along Interstate 5 in Chula Vista. There, starfish and egret designs cover the road shoulders. But that is more expensive and was done there because plants wouldn’t grow in the salty soil.
Stephen Alvarez, a CalTrans senior landscape architect, said making changes across all the region’s roadsides will take time. “To do a hairpin turn is not realistic,” he said.
“It takes so many years to build the infrastructure,” Alvarez said. “It’d be unrealistic to think that tomorrow we could do something else and still serve the functional needs of the roadside.”
CalTrans has begun using reclaimed water, Alvarez said. But expanding that purple-pipe system is costly, both for CalTrans and the city of San Diego, which provides the pipes. And such infrastructure may become irrelevant if the city continues pushing forward with plans for a full scale sewage-recycling system. That would turn reclaimed water into a drinking-water source.
Water’s economics pose a significant hurdle for the city and other water agencies as they continue calling for conservation. That message is expected to be amplified next year. Water deliveries from the Sacramento-San Joaquin River Delta, a major source of San Diego’s supplies, have been cut to protect an endangered fish, the delta smelt. The Colorado River, the region’s other major supply, has been suffering from prolonged drought.
As those conditions persist, businesses and large users say making upgrades that effect long-term conservation are often tough to justify within limited budgets.
John Dilliott, energy and utilities manager for the University of California, San Diego, the city’s third-largest consumer, said the school gets a faster payback from energy efficiency upgrades.
A campus-wide program that replaced more than 50,000 lights with energy-efficient bulbs cost $1.5 million and will pay for itself within four years, Dilliott said. Spending the same amount to expand the use of reclaimed water for campus cooling towers would pay for itself in 15 years, he said.
The university has made some upgrades anyway, planting drought-tolerant landscaping and switching to drip irrigation, which releases water more efficiently than sprinklers. It has a centrally controlled irrigation system and uses reclaimed water to irrigate large athletic fields.
“We’re still trying to do everything we can,” Dilliott said. “We understand it’s a problem and we want to help fix it. We’re not ignoring the problem just because the financial impact isn’t there. It’s coming.”
The city charges residential customers a higher rate as they increase use. It doesn’t do that for commercial and industrial customers, who pay a flat rate: $2.60 for every 748 gallons they consume.
Water agencies throughout the county are considering temporary drought rates that would increase water’s price to ensure conservation if supplies are cut next year. Such hikes would make up the lost revenue that would result from selling less water. Some agencies are considering making those structures permanent.
The Helix Water District is undertaking a complete rate restructuring to encourage conservation. Bigger users will pay more, said Mark Weston, the district’s general manager. Helix will create five classes: government agencies; businesses; multi-family residential; single-family residential; and irrigation.
Government agencies such as CalTrans, Helix’s largest user, will be told how much water they can use. District staff will examine CalTrans property and specify exactly how much water CalTrans needs. Weston said customers who exceed their allocation will pay at least 50 percent more for water.
“We’re going to send a huge message through our rate system,” Weston said.
That type of rate structure is vital for encouraging conservation, said Don Wood, a retired San Diego Gas & Electric energy efficiency advisor.
Without it, “there’s no carrot,” Wood said. “There’s no opportunity for [businesses] to recoup their costs or convince their managers that they can recoup costs.”
Ruiz said the city of San Diego will also consider that when it restructures its rates in 2011. If water is being used to create landscapes that aren’t natural, “then maybe it’s time to look at what we’re doing as a community and how we’re designing our landscapes,” Ruiz said.
Businesses want to be sure that if such rates become more prolific, they won’t be penalized unfairly. Mike McDowell, vice president of Atlas Hotels, which operates the Town and Country Resort in Mission Valley, said rate changes should take into account the benefits that water-consuming businesses provide: jobs, tax revenue, tourists.
Weston said the conservation rates for businesses pose a unique challenge. Helix plans to wait at least one year before applying those rates to businesses. “What do you do with a microchip factory versus a restaurant?” Weston asked.
But if the region’s water troubles continue, businesses, like everyone, will have to play a role, he said.
“If we use up all our available water and go to mandatory restrictions,” Weston said, “then everybody is going to be hurt by the fact that we don’t have enough water.”
This article relates to: Science/Environment