By Michael Avok
COUNCIL BLUFFS, Iowa (Reuters) - Senior citizens worked side by side with high school seniors on Thursday as efforts to fill sandbags continued here and across the Missouri River in Omaha.
After a short break for the Fourth of July holiday, work has started again to reinforce levees along the swollen river, which has received a record amount of rainfall and snowmelt runoff in June.
Piles of sand and hundreds of sandbags covered the parking lot of the Mid America Center, the Council Bluffs arena and convention center, as more than a hundred people turned out to continue flood prevention projects, from retirees to teens from a Kansas 4-H club.
Leland Christiansen of Council Bluffs was sweating after nearly two hours of filling bags.
"This is about my fifth or sixth time out here," the retiree said running his fingers through his white hair. "It's good exercise."
This season's flooding on the Missouri River has soaked property from Montana through Missouri, forcing residents to shore up protections and evacuate their homes.
North of Council Bluffs in Blair, Nebraska, U.S. Highway 30 remained closed for a second day Thursday as state workers built a barrier to keep the river from overtaking the road.
The closing means that with the exceptions of Omaha and Plattsmouth, Nebraska crossings between Nebraska and Iowa, all bridges are closed along a 228-mile stretch of the river from Sioux City, Iowa to St. Joseph, Missouri. Highway 30 is set to open Friday morning.
Flood preparations and levee monitoring will continue downstream from Gavins Point Dam at Yankton, South Dakota for weeks to come as the Army Corps of Engineers plans to keep water releases at the dam at 160,000 cubic feet per second until mid-month.
The Corps plans to scale back releases at four other upstream South Dakota dams by mid-month, moving Oahe Dam releases in Pierre, South Dakota to 150,000 cubic feet per second. The other dams between Pierre and Yankton also will see lower releases.
Forecasters predicted Wednesday that this summer's flooding season could rival the worst in United States history. In the "Great Flood of 1993," record-breaking floods from April to August cost more than $25 billion in damages in at least nine states.
Due to current high water levels and soaked soil, just a small amount of rain could trigger more flooding in areas that have already seen record flooding this 2011 season, according to the National Weather Service.
(Writing by Michael Avok; Editing by Mary Wisniewski and Greg McCune)