Mike Clarke, the former Davenport public works director who first brought HESCO barriers to the city as a way of fighting floods, said Wednesday he believes the barriers would have held if they had been built more strongly.
"It appears to me they (the city) deployed the HESCOS as they always have done it, the way I designed it," he said when contacted by the Times for his opinion.
"But they were fighting the last flood," he said. "I would not have gone into a 22-foot flood fight with just one line of HESCOS. No way."
Nicole Gleason, Davenport's current public works director, said at a news briefing Wednesday morning that the city was prepared for the level of flooding that had been forecasted.
At the end of day Friday, not only were the HESCO barriers in place, but they had been topped with about 15 inches of sandbags, which would have held for the forecast of 20.5 feet, she said.
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But when the flood forecast changed to 22.2 feet on Monday because of rain, it was too late to fortify them further, she said. "We didn't have time to erect another flood wall in the time we had."
Clarke said that for a higher flood, the baskets could have been double-stacked at the base, with another line on top for additional height. And baskets could have been placed perpendicular to the line every so many feet for additional strength.
"The weight of the HESCO barriers has to be greater than that of the river," he said. Clarke left the city abruptly abruptly in early 2016 in a move that was called retirement. But he had another job within six weeks, and he later explained he was forced out, adding that he and then-interim City Administrator Corri Spiegel had distinct differences of opinion. He now is the public works director of St. Pete Beach, Florida.
The HESCO barrier at Davenport's 2nd Street and Pershing Avenue breached about 3:30 p.m. Tuesday. Gleason said she still does not know exactly what happened, but it appears that the barrier was simply just shoved out of the way by the sheer strength of the water.
Or, there could have been a street washout below, she said.
As of Tuesday, barriers have been up for 48 days.
"We just haven't had anything like this happen before," she said.
The areas of Pershing Avenue/2nd Street and the Village of East Davenport have been of highest concern, she said at the news briefing. While Pershing has failed, the barriers in east Davenport still are holding, she said.
How the rest of the fortifications will hold up is unknown.
"They've worked very well in the past," Davenport Mayor Frank Klipsch said at the briefing. "We'll look at how they may work better in the future."
Another consideration is whether, with time, the sand inside the baskets gets so saturated that it liquifies. "That's a question to ask," Clarke said. "But because it's in a basket, that shouldn't have happened in 30 days."
The height, speed and weight of the water all has to be factored in, along with the likelihood of debris in the water that could puncture the baskets.
If city staff had any question about the endurance of the HESCO barriers, they could have consulted with the U.S. Army Corps of Engineers, Clarke said.
Gleason said Wednesday she isn't sure whether that happened.
Clarke said he had not been keeping tabs on the flooding situation in Davenport, but one of his sons still lives in Iowa, and his son's finance sent a text about Tuesday's breach. Over lunch Wednesday in Florida, Clarke watched the news briefing.
"It's a travesty," he said. "With better leadership and better planning, you wouldn't be in this situation. They're (city staff and officials) saying all the things you say when you know you screwed up."