Rathbun, Iowa — The Kansas City District, Corps of Engineers continues to monitor record water levels at Rathbun Lake.
"We are forecasting a spillway discharge to start within 24-36 hours," said Kansas City District, Chief of Emergency Management, Jud Kneuvean.
The flow through the spillway will start slowly and may increase in the next five days depending on precipitation in the basin.
Additional personnel have arrived at Rathbun Lake to assist, assess and advice other local, state and federal agencies. "Public safety is our first priority."
The Kansas City District Headquarters deployed 13 dam safety and flood fight experts," said Emergency Operation Center, Battle Captain Seth Laliberty.
The current forecast is the lake level will rise and begin to flow through the emergency spillway could occur as soon as tomorrow. The flow through the spillway will pass around the southwest end of the dam and eventually reach Little Walnut Creek that flows north of the city of Rathbun. This flow is likely to impact all public roads north of Rathbun.
The Corps of Engineers continues to coordinate with Appanoose County officials on potential impacts to roads and other facilities in the area.
Due to last Monday night's heavy precipitation, the Corps of Engineers stopped all releases from the lake to avoid additional downstream flooding. Beginning Wednesday morning increases were slowly increased and will remain constant at 2100 cubic feet per second.
Beginning Thursday morning, lake releases will be gradually increased and downstream conditions will be monitored. "The goal is to increase releases to 3,000 cubic feet per second, but the total release will be determined by downstream impacts and conditions." said Bill Empson, Chief of the Technical Support Branch for the Kansas City District, Army Corps of Engineers. Over the past few weeks, releases have been limited to 1,500 cubic feet per second to avoid downstream impacts. In response to increased flow through the normal outlet channel, additional rock will be brought in to prevent erosion of soil in the outlet channel.
During a flood fight, the Corps of Engineers usually provides assistance by providing communities with sandbags and technical assistance, loaning other materials and equipment, building emergency levees and hiring contractors. Kneuvean said, "Port-a-dams are being brought in from Rock Island and Omaha Districts to protect the fish hatchery. Sandbags and a sandbagging machine have arrived at the pump station to protect the drinking water plant."
Rathbun Lake is currently 22.5 feet above normal and with no additional rain is projected to increase 1.5 feet over the next five days. Rathbun Dam continues to
perform as designed and spillway discharge does not place the dam at risk.
News release July 21, 2010