Politics & Government

Landscape experts say Caltrans water-saving projects could harm trees

Gov. Jerry Brown’s January order to cut state-government water use 20 percent rippled through the bureaucracy early this year as high-level officials rushed to find ways to conserve.

California State University, Sacramento, President Alexander Gonzalez issued a statement about the school’s low-flow toilet conversion program. Parks and Recreation officials went a step further, announcing that they were closing some campsite showers and restrooms and setting up portable toilets. Lawmakers agreed to let the grass die in Capitol Park to “set an example in our front yard for people to follow in their front yards,” a state spokesman said at the time.

At Caltrans, Director Malcolm Dougherty issued a Feb. 7 memo that, among other things, ordered a 50 percent reduction in water used on its vast inventory of irrigated-landscape freeway areas.

The 30,000 acres of grassy plots, trees and permanent plantings cover an area roughly the size of Disney World and account for three-quarters of all the water Caltrans uses each year. Cutting irrigation watering in half, plus 20 percent cuts elsewhere, would more than meet Brown’s order.

To do so, Caltrans allocated $48 million for emergency no-bid contracts statewide to, among other things, upgrade irrigation systems and apply mulch.

In its effort to save water, however, Caltrans has approved new irrigation systems that arborists say are threatening the lives of mature trees on thousands of acres near California freeways, offramps and rest areas.

Experts contacted by The Sacramento Bee say trees best absorb water and nutrients at the edges of the root system on the outskirts of a tree’s canopy.

Caltrans, however, ordered a company working on several projects in the Sacramento area to install water lines running to the bases of mature trees.

The firm, WABO Landscape and Construction Inc., installed the lines for 40 or 50 trees in the greater Sacramento area and the Grass Valley/Nevada City area, co-owner Scott Esson said. The lines were installed to trees whose sole watering source had been sprinklers that the state has shut off to save water.

Base-watering older trees “is one of the biggest mistakes that homeowners make,” said Joe Benassini, urban forester for the city of Sacramento. “They water the base of their trees and in 10 years wonder why their trees are dying.”

Erika Teach, director of urban ecology for the Sacramento Tree Foundation, said that base-irrigating established trees doesn’t help them. After viewing photos of Caltrans water lines at the base of trees, Teach said the method “is not in line with the methods we recommend for mature trees.”

Chuck Ingels, horticulture adviser with UC Cooperative Extension in Sacramento County said, “When you have wet soil right around the trunk, you’re opening things up to fatal soil disease problems.”

If a tree isn’t watered appropriately, Ingels said, it becomes weak and prone to a borer insect invasion.

“They lay eggs near sunburned, damaged bark,” he said, “and the larvae feed on the cambium,” the tree’s growth-producing layer.

The experts interviewed by The Bee offered different opinions about how to best deliver water to a mature tree, whether by sprinklers, slow drip lines or the quicker-flowing bubbler lines that Caltrans installs. But all agreed that deeply watering around a tree at the edge of its canopy is the best practice.

Caltrans officials defended the systems they installed. Esson said the projects have been “a win-win” for the state, his firm and other contractors, and that Caltrans signed off on all the work performed.

Caltrans architect Chris Johnson said he has installed “thousands of acres of irrigation and plantings” and has “rarely seen tree failure using that method of planting irrigation.”

“(The single-bubbler system) is our standard,” said John Rodrigues, Caltrans chief of Northern California construction. He acknowledged that the department uses that standard for seedlings and young trees and does not have a separate policy for irrigating mature trees.

Asked whether the single-lime bubblers were a good idea, WABO’s Esson said, “That’s what I’ve been doing for 28 years,” and that he doesn’t think the practice is a “bad thing, and it certainly doesn’t waste water.”

Caltrans landscape inspector Larry Raupp, however, told The Bee that when he reviewed the Sacramento-area work this spring, he was “incredulous” that Caltrans officials would sign off on watering the bases of mature trees. He said he raised his concerns with superiors, who eventually took him off oversight duty for similar emergency conservation projects with another private firm.

In a June 12 email to Raupp, David Gamboa, a Caltrans Technical Services branch chief, cited “differences with your inspection philosophy and direction I had given you” in removing him as an inspector on the work.

Caltrans documents reviewed by The Bee show that as of April 10, the department had awarded 18 contracts to 15 private contractors, including $2.5 million to WABO to “upgrade the existing (irrigation) controllers. Modify existing irrigation systems and install mulch … around existing trees, shrubs and ground cover.” It also required the company to modify old, inefficient watering systems “to direct water in the most efficient way to the remaining landscaping.”

To expedite what officials considered emergency work, the department skipped its usual contract bidding and project planning processes. Instead it awarded the contracts to WABO and other firms that had worked on other Caltrans projects. The plans weren’t as detailed as they are with normal projects, said Esson, who served as WABO’s project superintendent.

“You could get a verbal agreement on a Friday and you’d start work on Monday,” Esson said. “Then you’d be working six days a week, 10 hours a day, and the scope of the work was never really defined.”

Caltrans tacks on a 21 percent markup for the contractors on no-bid emergency contracts. For example, wood mulch used on the eastbound Interstate 80 loop at the Riverside exit in Roseville cost WABO nearly $12,000. The state paid the company $2,500 more. WABO reported a day’s labor cost on the project totaled close to $3,400. The state paid the company nearly $4,100.

Rodrigues said that the markup compensates contractors “for things that aren’t in the direct cost of the labor and equipment,” such as workers compensation coverage and equipment insurance.

Raupp said he also raised questions about whether the payment system was encouraging more mulching than was necessary.

Raupp had told a director on a different project he inspected to keep mulch application to areas surrounding trees and shrubs and leave uncovered areas without permanent plantings.

But he said his supervisor had noticed a WABO project at Interstate 50 and Mather Field Road had been fully covered in mulch. It looked nice.

“He asked me, ‘Larry, why are you being so skimpy with the mulch?’ ” Raupp recalled.

That led Raupp to look at the Mather Field Road site and others WABO had worked on. Several were covered with mulch that he believed served no water-conserving purpose and worse, went beyond the scope of the contract.

“Why would you put mulch where nothing you want to keep is growing?” Raupp said. “I can tell you why. It’s easy money for the contractor.”

Caltrans and WABO both said that mulch on open areas cuts down on weeds, prevents erosion and reduces maintenance costs.

Esson also denied creating busy work to pad his company’s bottom line. He cited WABO’s half-century of state-contract jobs and the invitation to do the emergency work as proof of the firm’s ethics.

“These were state-awarded contracts, run and inspected by state personnel,” Esson said. “We did what we were asked to do.”

Raupp raised his objections to his boss and then to his boss’s boss.

“We agreed,” Rodrigues said. “Now we’re mulching less.”

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