Near Breach on Kadashan Bottom Dam No. 2

Event Shows Need for Maintenance, Repair and Rehab

During April 8-10 over eight inches of rain fell in the Kadashan Bottom Dam No. 2 watershed, more water than the principal spillway could handle in that time period. The continuous flow through the secondary spillway created a headcut that eroded its way back up the spillway into the lake. While the spillway received significant damage, the dam held and did not fail.

The Kadashan Bottom Dam No. 2, approximately four miles west of Coweta and one mile east of the Tulsa County line, was constructed in 1979 by the USDA Natural Resources Conservation Service under the Watershed Protection and Flood Prevention Act of 1954. Wagoner County Conservation District serves as the local sponsor. The dam is 36 feet tall, has a 33-acre reservoir and a 1,946-acre drainage area.

As the secondary spillway began to flow, the county emergency management agency and the sheriff’s department blocked off roads downstream from the dam. Classified as a low hazard dam, with no homes or businesses immediately downstream, a threat for loss of lives was not indicated if the dam had breached.

“This dam was in good working order but still suffered the effects of this major storm event on top of heavy rains earlier this spring and the massive amount of rain our state experienced in 2007,” said Scotty Herriman, president of the Oklahoma Association of Conservation Districts. In 2007 more than 25 other dams suffered similar damage from storms and heavy rains, he said. “Our flood control structures are in desperate need of rehabilitation work, especially in light of this record rainfall,” Herriman said.

OCC submitted to the state Legislature an emergency funding package of $30 million including $8.8 million for dam rehabilitation, $7.1 million for operation and maintenance and $11 million to repair other conservation practices such as terraces, waterways, ponds and riparian areas.