New construction on the Oroville Dam spillway in Butte County, Calif., has developed hairline cracks. The spillway, damaged in February by a combination of corrosion and record rains, has been a cause for concern.
This upcoming month, the California Department of Water Resources (DWR) rushes to make sure the dam is strong enough to withstand the winter. The contractor, Kiewit, is using a sturdier cement than what was available 50 years ago when the dam was originally built.
The DWR told the dam’s federal overseers in a letter that the added layer of steel reinforcement caused the hairline cracks and is not a cause for concern. The letter said that, “the hairline cracks are a result of some of the design elements included to restrain the slabs and produce a robust and durable structure.”
