Building an island
September 01, 1993
by Teresa Acklin
Elevator workers, volunteers race against time and the river to save a grain facility in the flooded U.S. Midwest.
When the Mississippi River began to rise in June, Louis Dreyfus Corp. employes at the company's river elevator at Burlington, Iowa, U.S., weren't too concerned. Although the 16,000-tonne facility sits in a flood plain unprotected by levees, only a record-breaking river stage more than 6.5 meters would cause major problems.
But each day, river-crest forecasts, like the muddy water itself, continued to creep higher. As the river stage approached 6 meters, elevator employes suspected they would need to seal the rail pit, which also sits at about 6 meters.
Still, at that point “it was no big deal,” said Bob Sondag, Louis Dreyfus regional manager at the Pekin, Illinois, U.S., office.
But on June 30, the river was still rising. The elevator went to a 24-hour schedule.
The five employes pulled motors and electrical equipment out of tunnels. They began filling and laying sandbags around the office, the motor control room and the truck pit, all sitting at 6.5 meters. Protection of the truck pit was particularly important; because the concrete silos are countersunk, water entering the pit would cause a 2.5-meter flood in the bins.
Rising river breaks old flood record.
By Friday, July 2, the situation clearly had become serious. River stage a day earlier had reached the old 6.5-meter record, and the water was still rising.
Conditions continued to deteriorate. By Wednesday, the river completely surrounded the elevator. The crest was not expected until late Friday or early Saturday at more than 7.5 meters.
Some employes were ferried to the site, while others filled sandbags from dry land about 0.5 kilometers from the elevator. A neighboring business lent its large, front-end bucket loader to deliver the sandbags to the elevator.
“We were building an island,” Mr. Sondag said.
Despite these efforts, the five employes feared they would be unable to keep up with the river. Mr. Sondag called on other Louis Dreyfus employes in the region to come to Burlington to assist with sandbagging.
As Wednesday wore on, the water continued to rise, pushing the sandbag-filling operation further and further from the elevator. At the site, the crew continuously operated 10 pumps to counter seepage from the water's increasing pressure on the sandbags.
Sometime late Wednesday, Mr. Sondag said, someone realized the group had overlooked a potentially devastating detail. Because the water posed no threat to the concrete silos themselves, they had not been sandbagged.
But the silos' aeration fans were located only about 1 meter above the ground. The fans' 36-cm ducts leading straight into the grain were unprotected.
Wednesday night, the workers, fighting currents, waded out to the silos. The fans' bolts and mountings were under water, but the workers were able to pull out the fans and seal the ducts with sandbags.
On Thursday, the ducts became submerged completely, but the sandbags held, protecting the grain.
But the river continued to rise. By early morning Friday, the sandbag levees around the truck pit and office were weakening. The pumps were losing ground, and the facility was in imminent danger of flooding.
What had started a few weeks earlier as an inconvenience had become a desperate effort to save the elevator.
Volunteers respond to call.
A local radio station broadcast a call for assistance throughout the Burlington area, and by 1 p.m., about 40 volunteers were filling sandbags at the dry site near the elevator. More than 25 Louis Dreyfus employes arrived from other sites.
By late afternoon, the pumps were beginning to catch up with the seepage. The sandbag walls, initially 1 meter high by three bags wide, were approaching 2 meters high and 2.5 meters wide and were holding. By 5 p.m., everyone knew their efforts had saved the elevator.
Overnight, the river crested at 7.5 meters.
Mr. Sondag said some 10,000 sandbags and 20 to 25 tandem truckloads of sand were used to save the elevator, also saving the company at least U.S.$250,000 in damages. In addition to grain contamination, flooding would have caused severe damage to the electrical, mechanical and control systems, he said. About 14,000 tonnes of maize, soybeans and sorghum were in storage.
After the July 9 crest, the Mississippi River at Burlington receded by about 1 meter before cresting again on July 26 at slightly more than 7 meters. Forecasts indicated the river would not reach the earlier level of 7.5 meters.
Mr. Sondag said elevator operations would return to normal when the river reopened to barge traffic, expected to be sometime this fall.