Workers retiring an underground water pipeline in Oakland accidentally dumped 120-170 cubic yards of cement into a nearby creek Wednesday morning, an East Bay Municipal Utility District spokeswoman said Thursday.
A contractor with EBMUD was working on filling the 2-mile-long, 24-inch-wide old pipeline with cellular cement, a standard practice by the district for taking a pipeline out of service, but someone accidentally left a valve on the pipe open, allowing the cement to flow into Glen Echo Creek, EBMUD spokeswoman Abbie Figueroa said.
The pipeline and creek are underground where the crew was working, but a neighbor near Broadway Terrace, downstream from where the creek emerges, noticed the substance flowing through the creek, Figueroa said.
EBMUD was alerted to the spill at about 11 a.m. and shut off the valve around noon.
A storm drain was dammed about a half-mile down the creek to keep the substance from flowing into Lake Merritt and the Bay and the water was diverted into a sewer, Figueroa said.
Biologists are testing downstream to determine if any of the cement made it past the dam.
State regulatory agencies were alerted to the spill to take appropriate action, Figueroa said.
The cleanup is expected to take at least the next two days.
Crews are manually shoveling the “goop” out of the creek and they plan on flushing the underground portions of the creek later Thursday.
Investigators have still not determined whether it was the contractor, a subcontractor or EBMUD workers who accidentally left the valve open.
“It’s a mistake, it should not have happened…We’re going to be looking into this thoroughly to find out how it happened and make sure it never happens again.”