Summer floods prompt repairs to Oklahoma’s flood-control dams

The month of June 2016 saw state of emergency declarations by Oklahoma Governor Mary Fallin due to flooding, and the completion of repairs to flood control dams that were damaged during last year’s severe storms.

According to the USDA Natural Resources Conservation Service (NRCS) Water Resources Office in Oklahoma, flood control dams prevented $19.3 million in damage in June 2016. In total, dams have prevented $83.6 million in damage this year so far.

In light of the flooding Oklahoma has experienced despite having the most flood control dams in the nation, April Burns, acting state conservationist for water resources said “It’s important to remember that Oklahoma’s network of 2,107 flood control dams are designed to control and reduce flooding, not prevent it. The damage we suffered would have been much worse were it not for these dams.”

The town of Maysville saw particularly heavy flooding on June 12. Five of the six dams that protect the town along Beef Creek had water flowing through their auxiliary spillways. Auxiliary spillway flow occurs when water from upstream exceeds the capacity of the main spillway and must divert around the dam. Auxiliary spillway flow is an indicator of extremely heavy rainfall.

Throughout the June 12 storm in Maysville, NRCS staff were joined by Garvin Conservation District and Oklahoma Conservation Commission dam inspection staff to monitor the situation at the dams and ensure they continued to function safely.

“I wish I knew how many times those dams were walked across and the depth of water in the spillways was measured that day. It was a lot!” said Brandon Chandler, NRCS District Conservationist for Garvin County.

Repairs to Big Wewoka Dam No. 22 in Seminole, otherwise known as Sportsman Lake, have been completed. During storms in 2015, rushing water caused severe erosion in the area where the dam releases water downstream. Left untended, the erosion would worsen in future storms, potentially leading to a failure of the dam and loss of life and property downstream. The dam was repaired using funds from the NRCS Emergency Watershed Protection (EWP) Program and Oklahoma State Emergency Fund. EWP pays 75 percent of the cost of repairs and allows states to match the remaining 25 percent with direct funding or in-kind contributions such as labor.