As California's water woes continue to stress local trees and inflate water rates, Palo Alto officials are preparing to move ahead with a $35 million project that would significantly increase the city's supply of "drought-proof" water.

The City Council on Monday will consider approving an Environmental Impact Report for a major expansion of the city's recycled-water system -- a project that would bring recycled water to south Palo Alto and the Stanford Research Park. If the council OKs the project, as recommended by city staff and the Utilities Advisory Commission, the city would pursue grant funds for a program that officials hope could transform how water is viewed. The vision calls for greater differentiation between types of water, with potable water generally reserved for drinking and recycled water used for things like landscaping, toilet flushing and processing.

This project would be the second major expansion of a system that has been in place since the early 1980s, when recycled water began to flow to the Shoreline Golf Links in Mountain View. The delivery system was later expanded to the Palo Alto Municipal Golf Course, Greer Park and the areas around the Regional Water Quality Control Plant in the Baylands. Later proposals to expand the system were not pursued after city officials deemed them too expensive.

Now, with the drought stretching through its fourth year, city officials believe the time is right to pursue with the expansion. Karin North, watershed protection manager with the Public Works Department, noted that the city now has four different companies trucking recycled water to customers.

"There's a whole new industry that's been coming because of the drought," North said at the Sept. 2 meeting. "We did not, a few months ago, have four recycled-water haulers essentially selling our recycled water to customers."

In the new phase, pipelines would run past Mitchell Park, delivering recycled water there, and into Stanford Research Park, home of large corporate campuses with lush lawns. A staff report from Public Works notes that this area was chosen because it is "the largest concentration of customers with irrigation needs" in the city.

The project has drawn some concerns from Stanford University, which owns the park, and from groups such as Canopy, which urged the city to make sure that the salinity levels in the recycled water don't have a negative effect on local trees. To address these concerns, the city has committed in the environmental report to monitor salinity on a monthly basis and, if needed, undertake one or more strategies to reduce the saline level. The proposed strategies include exempting redwood trees from recycled water; blending recycled water with other water that has lower salinity; and treating the water.

The project has received strong support from the Santa Clara Valley Water District, which has its own long-term plans for purifying wastewater so that it's potable. Gary Kremen, chair of the water district's board of directors, noted that the district has some money that could be used for this project, including funds from Proposition 1, a $7.5 billion bond that California voters approved last year for water projects. Hossein Ashktorab, manager of the Recycled Water Unit at the Santa Clara Valley Water District, also spoke in glowing terms about Palo Alto's latest effort to replace potable water with recycled water where suitable.

"It's really water for the future," Ashktorab said. "Recycled water is drought-proof and it's going to be locally controlled so we don't have to import it from anywhere."

Palo Alto is by no means the only city that is taking a closer look at improving and expanding use of recycled water. Mountain View, one of Palo Alto's partners in the Regional Water Quality Control Plant, has expressed an interest in analyzing the prospect of treating and blending recycled water to improve quality, according to the Public Works report. And Sunnyvale is now upgrading its wastewater-treatment plant so that treated water can be used for its groundwater-recharge operations, according to staff.

In Palo Alto, Phil Bobel, assistant director at Public Works, told the utilities commission that the city will probably eventually "have a bunch of different kinds of water, and we're going to match that water with the need."

"Everyone will sort of have to go with the flow here and utilize the water that is correct for their need," Bobel said.

The Utilities Advisory Commission had few qualms about moving the project along. In its Sept. 2 discussion, all five participating members supported the staff recommendation. Commissioner Judith Schwartz said she very much likes the idea of a "targeted system," which she called "the wave of the future." Commissioner James Cook agreed.

"With water costs going up ... and our preference to use our beautiful Hetch Hetchy water for drinking, I'm all for going with the staff's recommendation on this," Cook said.