A levee breach along the Missouri River just south of the Iowa/Missouri border prompted a mandatory evacuation for about half of the town of Hamburg, Iowa, on Sunday.
Officials describe the breach as a “boil” — a hole of less than an inch-and-a-half in diameter. It created a small geyser of water that began spraying onto the dry side of the levee.
The National Weather Service warns Interstate 29 will be flooded if the levee fails.
This geyser or boil was found about two miles south of the Iowa/Missouri border, but Derek Hill of the Iowa Homeland Security and Emergency Management division says the water would flow back into Hamburg, Iowa if the levee fails.
“Because of the topography there — it’s fairly flat land; there’s not a lot of elevation change — and the hydrologists explained that’s more than likely the direction the water would flow,” Hill says.
A Black Hawk helicopter was dispatched Sunday to the levee to drop one-thousand pound sandbags in hopes of plugging the hole.
Hill briefed reporters by phone on Sunday afternoon. “(You) use a helicopter rather than putting personnel on the level because of the danger of a…larger levee breach at that time,” Hill says.
Hill has reviewed flood prediction maps from the Army Corps of Engineers, and he’s urging residents in the expected flood zone to move.
“So the Missouri River, at a few points, is going to be extremely broad,” Hill said. The water will stay for weeks, in some cases months, and Hill says not only will mold begin to grow on the structure of a home, but even items which are above the water line in a home will begin to get moldy as well.
“This water is coming…The people that live within the inundation area need to be talking to their county officials as to how deep the water is going to be. Is there a way to mitigate against that water or do they need to be moving?” Hill asks.
“If they have vehicles or farm equipment that are out there, or anhydrous tanks, they need to be moving them to higher ground so they’re not floating down river,” Hill said. Propane tanks also need to be tethered down or moved out of the flood zone.