Repairs to a failing 6-inch-diameter sewer pipe running the length of a small canyon on Alcott Street were successfully completed without the further removal of trees. The less invasive methods employed at the urging of adjacent homeowners actually saved the city $20,000, announced Chris Toth, deputy director of wastewater collections, at a Peninsula Community Planning Board meeting June 15.
“It was a good surprise,” Toth said of the city’s reaction to the savings.
Last November, city crews razed the bottom portion of the overgrown paper street in order to reach and replace the underground pipe. More than a dozen small trees and a towering, four-story-tall eucalyptus were removed in the process. The Metropolitan Wastewater Department claimed that two sewage spills during the previous eight months constituted an emergency and necessitated the extreme measures.
Throughout December, outraged residents with homes bordering the once lush oasis pressured the city to leave the remaining section of the canyon in tact and finish the rest of their work without the mass removal of vegetation.
After meetings facilitated by District 2 Councilman Kevin Faulconer, the city and community agreed upon a pipe bursting technique for the remaining section of decrepit concrete.
On April 26, contractor Zondiros Corporation inserted an Insituform fiberglass lining into the pipe through a manhole at the top of the canyon and exited it through another manhole about halfway down the hill. The liner was expanded, heated and cured to form a hardened resin that sealed off all holes, including lateral connections, which were subsequently reestablished robotically.
Roughly 145 feet of pipe was replaced or rehabilitated for $31,500, said Toth, adding that trenching the same area would have cost an estimated $51,000. Because the technique did not disturb the surface of the soil, the city saved on erosion control, revegetation work and tree removal in the final section.
In an effort to maintain good relations with Loma Portal residents, the city has recruited their leadership in developing a revegetation plan for the bare section.
“I think it’s going to be in many ways up to [the residents],” Toth said of selecting particular plants and trees.
Meetings have been tentatively scheduled for July to decide how to best spend the $8,000 allotted for the canyon’s restoration, and whether to use volunteer labor instead of city forces to stretch the dollar further.