Pipe fitting bursts on Hillard Avenue, street section collapses into sinkhole
La Cañada Irrigation District employees worked to repair to a 15-foot sinkhole in the 4700 block of Hillard Avenue Tuesday after a broken pipe fitting led to leakage that caused a sewer trench to subside, water officials reported.
Doug Caister, the water district’s general manager, said the 40-year-old fitting caused water to leak into the gutters along Hillard Avenue. On Saturday, La Cañada Irrigation got calls from residents in the area who noticed water gushing on one side, and then both sides, of the street.
“We got a call from someone who’d seen the water on Friday night and didn’t know what it was,” Caister said Tuesday. “So we went up there Saturday … and we barricaded it.”
By Sunday, the leakage had saturated the ground packed under the street, causing the sewer trench to subside, Caister said. That’s when the portion of the asphalt on Hillard collapsed in a sinkhole estimated to be about 15 feet long by 10 feet wide.
“It got worse from Saturday to Sunday,” Caister said, adding that employees returned the next day and saw a sinkhole. “There was quite a cavern there over the sewer trench. It’s a huge one.”
He explained the ground around the sewer trench may not have been fully compacted when sewer lines were installed on Hillard Avenue, causing the saturated ground to give way some 200 feet north of where residents saw the leaking water. The fitting itself may also be to blame, Caister surmised.
On Tuesday, workers were busy removing pieces of collapsed asphalt from the sinkhole. By then, a temporary patch had been placed on the burst pipe fitting. Caister said the hole will be back-filled and covered over with temporarily asphalt mix and possibly a steel plate to allow Hillard to completely reopen to traffic.
Sometime after that, a La Cañada Irrigation District crew will return to make permanent repairs and then fully repave the street surface, Caister said.
Twitter: @SaraCardine
