A utility official says repairing the Wanapum Dam will likely require anchoring the entire spillway to bedrock, not just one section where a crack was discovered.
Grant County Public Utility District chief financial officer Kevin Nordt said Tuesday his $61 million repair estimate includes the cost of installing anchors on each of the spillway's 12 monoliths or massive concrete sections.
The Wenatchee World reports when the Columbia River dam was built in the early 1960s designers believed its mass alone would be enough to hold it in place.
The reason for the 65-foot crack that was discovered Feb. 27 has not officially been determined, but officials have said it could have been caused by water pressure. The reservoir has been lowered for repairs.