Someday, Cesar Chavez Boulevard will be a glamorous, tree-lined thoroughfare equipped with clever design touches that allow cars, bikes, and pedestrians to share the street safely and efficiently. But today is not that day. Today, Cesar Chavez is a gnarled maze of traffic pylons, heavy equipment, and congested traffic. Yet amid all the construction chaos, one new feature is rather conspicuous: a large white tent that was recently erected at the intersection with Florida Street.
For residents of Bernalwood’s north side, the purpose of the tent has become the object of much conjecture and speculation. Some say the the tent will serve as the venue for a Teatro ZinZanni-style pop-up dinner theater, with the menu selected and prepared by chefs from the Hillside Supper Club. Others cite rumors which say the tent will play host to the bar mitzvah reception of young Herbert Schwartzmann of Peralta Avenue, who requested a “Bob the Builder” theme.
Fellow citizens, your Bernalwood investigative team is here today to tell you that those theories are incorrect. The truth of the matter is that the tent shelters the access point for a high-tech effort to stabilize the subterranean 19th century sewer pipe, which was recently supplanted by the brand-new pipe installed on the north side of the street.
The stabilization effort uses a technology called Cured-In-Place-Pipe (CIPP) that involves stuffing giant, resin-impregnated felt tubes into the old old sewer pipe. You can see a pile of the felt tubes stacked up here:
The felt tubes are become solid when they are cured with hot water, which stabilizes the old sewer pipe — eliminating the need to dig up the street to remove it.
Here’s an explanation of the process from the website of Sak Construction, which is performing the work on Cesar Chavez
During the wet-out process, the felt tube, coated on the outside with a continuous impermeable layer of polyurethane, is resin-impregnated, fully saturating the felt so that no voids or pockets of air remain in the tube. The wet-out liner is inverted into the existing pipe using a hydrostatic head or pressurized air. As a result, the resin-saturated side of the liner interfaces with the wall of the existing pipe. The reverse side of the liner—which is coated with polyurethane—thus becomes a smooth interior surface to effectively carry the rehabilitated pipeline’s flow.
Once the liner is in place throughout the entire length of the pipeline that is being repaired, we inject hot water or steam to cure the liner resin. When properly cured, this provides a continuous, jointless “pipe-within-a-pipe” and restores structural integrity to the damaged pipe.
This video shows how all the pieces come together:
PHOTOS: Courtesy of @SomaFMRusty