OAKLAND, Calif. (KTVU and wires) – The concrete spill in an Oakland creek is worse than initially thought, an East Bay MUD spokeswoman said Friday.
An additional 150 to 200 feet of contaminated creek was discovered by a resident Thursday evening.
Andrew Hughan with the U.S. Department of Fish and Wildlife said the new damage was found up creek and was overlooked because crews were focused on cleaning up the area downstream the day before.
"We were so focused on getting that cleaned up because that is where residents were that we frankly did not do a great survey," Hughan said. "We'll do a better job next time."
Fish and Wildlife and East Bay MUD officials obtained maps from the City of Oakland to do a thorough survey of the creek. So far, a half mile portion of the creek from Harbord Drive and Florence Avenue down to the Claremont Golf Course is affected.
The general manager of East Bay MUD said the agency and the contractor take full responsibility for the damage. So far, dozens of insects have died along with two birds.
The spill took place Wednesday when a non-standard valve turned the wrong way caused about 12 truckloads of cellular cement to be pumped into Glen Echo Creek.
The mix was not considered toxic to humans, but at least one bird has died and another was sickened by the spill.
The accident happened while an EBMUD subcontractor was working on replacing a 2-mile-long, 1930s-era pipeline that supplied water to 13,000 homes in the Oakland Hills.
The new pipeline has already been built and is in use. Before abandoning the existing, degraded pipe, the district planned to fill it with a lightweight cement to solidify it and prevent any structural issues.
But despite an inspector reporting the more than a dozen valves along the 24-inch-wide pipe were closed, when a subcontractor began pouring the cement, it flowed from an open valve into the creek.
The valve turned in an opposite direction than most of the district's 70,000 valves, so while the inspector thought it was closed, it was in fact wide open, Figueroa said.
A neighbor in the Clarewood Townhouses noticed the cement flowing into the creek and reported it at about 11 a.m., Figueroa said. The utility district responded, halted the pumping immediately, located the open valve and closed it off by about noon.
The substance – a lightweight cement with a foaming agent called "cellular cement" that dries into a spongy material called cellular concrete -- turned the creek into a light gray goop that crews were scooping, shoveling and vacuuming from the creek bed on Friday.
Figueroa said the clean-up would last through the weekend, but how long after that is undetermined. She said crews would remain on site for as many days as needed to remove the concrete.
"We're very dismayed that this happened," Figueroa said. "We are working very hard on clean-up efforts and trying to get that done as fast as we can so we can move on to the restoration of the creek."