Utility officials today met with North Fair Oaks neighbors to discuss various options that would prevent a centuries-old oak tree from being cut down to make way for a multi-billion dollar water system upgrade in San Mateo County.
The valley oak, which arborists have agreed is more than 250 years old and neighbors have nicknamed "Granny," stands in the path of a $4.6 billion project to seismically upgrade the Hetch Hetchy water delivery
The tree stands on San Francisco Public Utilities Commission property where a new water supply pipeline is replacing two installed in the 1920s and 1930s that are not seismically secure.
The scenarios presented at this morning's meeting included moving the tree to another location, tunneling the pipeline under its roots, and a "trenching" method that would require trimming the tree's roots and burrowing a pipeline around or through them, SFPUC spokesman Tyrone Jue said.
The trenching option, which neighborhood spokeswoman Mary Ann Mullen said could cost as low as $60,000, was least favored by the utility, Jue said.
"It leaves the pipe too close to the roots," Jue said, which jeopardizes the pipeline's seismic integrity.
Moving the tree to another location would be the most expensive process at $350,000, Jue said. It does not appear likely to happen since the tree would not be able to be moved very far.
The 80-foot-tall oak is so big that it could not be moved without temporarily removing major power lines to get it by, Jue said.
The tunneling option, which would cost an estimated $309,000, is the one most favored by the utility.
"Tunneling is one of the options we're continuing to move forward on," Jue said.
The tunneling option would include an agreement in which the utility would hand over ownership of the strip of land where the tree stands to an association of neighbors, who would assume liability, tree maintenance and providing increased public access, Jue said.
"It would take some legwork," Jue said. "But if we could turn it into a mini park or garden where everyone could enjoy the tree, it would be a win win."
Mullen said the SFPUC is moving ahead with the tunneling scenario without completely considering the trenching option.
"We thought that we were going to explore more fully the modified trenching opportunity," Mullen said. "They really closed down the collaboration on this."
The two sides will meet again in two weeks.