A new project aimed at cleaning up the arboretum waterway could show improvements in the appearance and smell of the water as soon as this summer.

The project, which dates back at least to 1999, calls for redirecting reclaimed water into the waterway, to freshen it up and make it more like a flowing creek.

Of course, the waterway is not a creek at all. It is a long, narrow 10-acre pond with no natural inflow other than rain and storm runoff. In the summer, the water becomes stagnant — and that lends itself to algae growth, which in turn produces the weird green colors and the smell.

"It is kind of not that appealing and it doesn't smell that great," said Rosemary DiClementine, a library assistant at the School of Law. "It's not that offensive," but enough so, she said, to make her "try to focus on the trees" during her lunch hour walks.

Indeed, an arboretum-sponsored survey in 2001-02 found that more people by far were critical of the arboretum Waterway than any other feature of the arboretum, and they wanted arboretum officials to address the problem.

"So, we're very pleased with the efforts of the campus and provost's office to help us address the problems," Arboretum Director Kathleen Socolofsky said.

The project basically involves an old pipeline, a new connector and a couple of valves. The cost is about $375,000, relatively cheap compared with other campus construction, said David Phillips, associate director of facilities in Operations and Maintenance.

Best of all, said Sid England, the university's director of environmental planning, "We have kind of a unique situation that allows us to do this without increasing our use of water."

So where will the water come from? The campus's wastewater treatment plant, after the water has been fully treated to government standards. Today, that water ends up legally in the south fork of Putah Creek. And that is where the water will still end up, but only after taking a 2¼-mile-long detour through the waterway.

To get treated wastewater into the waterway, the university plans to use a pipeline that formerly carried water from the old wastewater treatment plant to Putah Creek. The university abandoned that line when the new wastewater treatment plant opened closer to Putah Creek. Now the university will simply send wastewater back through the pipeline, this time going toward campus and not away from it.

Circulation upgrades

The treated wastewater would enter the waterway near the waterway's midpoint, so the resulting circulation would be only on the west end of the waterway. To help circulation on the east end, the university plans to pump water from the waterway to the wastewater treatment plant.

"I think it's great. I can't believe it," said Professor Bob Powell, chairman of the Chemical Engineering and Materials Science Department, when informed that his ad hoc committee's nearly 6-year-old idea was nearing reality. "It's really a tribute to the people who have been pushing this behind the scenes."

And while the project is expected to improve water quality, Powell noted: "There's no reason why it shouldn't work. You're certainly not going to see the muck that we end up with, particularly in summer.

"It should be the difference between night and day," Powell said. When the waterway clears up, he added, "You can take a picture of me swimming in it."

In doing so, he would be swimming in campus wastewater — wastewater that had been through what is called "tertiary," or three-phase, treatment. Tertiary treatment produces an outflow that "is suitable for reclamation uses where human exposure is generally unrestricted, including irrigation of parks, schools and residential areas," according to an environmental planning document for the waterway improvement project.

Powell's offer notwithstanding, swimming is not allowed in the waterway, nor is boating or other recreational contact with the water. Nevertheless, signs would be installed to indicate that the waterway contains treated water.

"Tertiary-treated recycled water is generally odor-free," the document states, "and discharge into the arboretum waterway would be expected to reduce the potential for odors that are caused by the existing dry-weather degraded water quality conditions."

The lack of continuous flow is only one factor that contributes to the waterway's smell. Rapid algae growth also stems from what the environmental document describes as "abundant nutrients from decaying organic debris both on the water surface and on the channel bottom, fertilizers in runoff, and fecal matter from the resident duck population."

"As a result, the water typically has a pale green cast and is frequently bright green," the document states. "Occasionally, dense mats of algae form on the surface, creating unsightly conditions and odors."

The improvement project's environmental review process has about three weeks to run, and after that the project should be easy to set up.

If the inflow of treated wastewater proves successful on the west end, the university could consider building a pipeline to put the entry point at the far east end of the waterway.

Peter McFadden, a Davis accountant who walks regularly in the arboretum, said "nothing strikes me as negative" about the waterway's color or smell. He said "having a little motion in the water" would be nice, but added: "I will continue to enjoy it thoroughly if it continues exactly as it is."

He and DiClementine said they hoped the university, in planning to put treated wastewater into the waterway, has set up safeguards to protect wildlife.

In fact, the environmental document states that the university will continuously monitor the waterway's water and automatically shut down the wastewater diversion if problems develop.

Also, the university must consult with state water officials when starting the diversion, to check the quality of the standing water in the waterway. If the water quality in the arboretum waterway were substandard, say, because of too much algae, then there could be no diversion until the project met discharge permit standards. Otherwise, the substandard water could be pushed into Putah Creek — and the university's discharge permit forbids that.

University planners added this consulting requirement to other mitigation measures previously established for campus construction projects. With all mitigation measures in place, the university has declared that the waterway improvement project would not have a significant adverse effect on the environment.

The environmental report is available for review on campus at the Office of Resource Management and Planning, 376 Mrak Hall, and in the reserves at Shields Library; and off campus at the Yolo County Library, 315 E. 14th St., Davis. The report also is available online, www.ormp.ucdavis.edu/environreview (click on "Current Projects" and then look for under "A" for Arboretum Waterway Improvements). Comments are due by 5 p.m. May 24. They should be directed to John Meyer, vice chancellor of Resource Management and Planning, UC Davis, One Shields Ave., 376 Mrak Hall, Davis 95616, or e-mailed to environreview@ucdavis.edu.