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The HESCO barriers could only take so much.

After holding back major flooding for months in Burlington, a temporary sand-filled barrier breached Saturday afternoon, causing some residents to flee and the Mississippi River to encroach on a portion of the downtown.

While the breach wasn't as far-reaching, it had striking similarities to the HESCO failure a little more than a month ago in Davenport that drowned the downtown and closed more than 30 businesses.

Burlington's barrier held steady as the Mississippi River rose toward historic levels and proved its strength against Davenport's temporary flood protection. But as rain added to the already swollen river and high water continued to flow downstream, Burlington's HESCO wall failed to hold up.

Unlike Davenport, Burlington is in the early stages of constructing a permanent flood wall. Temporary barriers were used to fill in the places where work has yet to begin. 

Burlington City Manager Jim Ferneau said the HESCO barrier had been in place for around 80 days, lasting through several crests, before the barrier failed south of Memorial Auditorium.

"We canceled events and had people move their cars, knowing that we were using the HESCOs too high. We had water at about 7 feet up on those HESCOs and carrying a lot of head pressure from the river current," he said. "We knew there was potential to have an issue." 

The city had been monitoring, and in some cases patching, parts of the barrier. But the spot where the wall failed was not of great concern. 

In the area of the breach, Ferneau said the land is porous, which made it difficult to find a sturdy base when placing the wall. HESCO barriers have failed nearby in the south end in previous years. 

Crews will not be able to evaluate damage or the exact cause of the breach until the flood waters recede.

When the river retreated in Davenport, city officials learned it wasn't the ground, but the strength and stacking of the barrier that caused the failure. The barrier did not hold up as the river rose higher than expected. And the city throwing sandbags on top of wall made little difference.

Davenport rebuilt its flood wall ahead of more flooding, placing HESCO barriers in different locations. Public Works Director Nicole Gleason said the wall is so far holding strong.

Many in Burlington are defending the city's use of HESCO barriers, a system used for years with few problems, Ferneau said. Some argue the wall was simply holding back too much water for too long.

"I think they've been up too doggone long. Like anything that's temporary, it's not meant to stay there forever," said City Councilman Jon Billups. "We've had some repair projects on the riverfront, so city staff did everything they could to prevent it. I don't blame the HESCO barriers." 

Officials with HESCO denied to speak on the record. 

On Tuesday, most Burlington businesses were back at work, with at least one exception. The Burlington Memorial Auditorium and Port of Burlington remained flooded, and the Market Street lift station remained offline. 

Can we be doing more?

Rather than pointing to an inadequacy in HESCO protection or the city's flood fighting efforts, some in Burlington have questioned whether the U.S. Army Corps of Engineers is doing enough to protect riverfront communities. 

"We came in this season with a river that was just below the beginning of moderate flood stage, and (the Corps) had only half of the gates open," Ferneau said. "Coming into this season, when the Corps was releasing projections about a lot of snow melt occurring, we could have had the river a lot lower if the gates would have been opened sooner." 

Chris Trefry, water control chief for the Corps in the Rock Island district, countered and said the dams are not used as a flood management system, but to manage navigation on the Mississippi River.

"The dams are operated to maintain a nine-foot navigation channel on the Mississippi River," he said. "So we hold the pool to maintain that channel, and as the river comes up and there's more flow from upstream, we open the gates to maintain that pool at the same level." 

Unlike many of the others within the lock and dam system, Lock and Dam 19 in Keokuk is privately owned by energy company Ameren Missouri, which maintains the pool to fit its own needs to generate hydroelectric power.

Billups has argued those overseeing the lock and dam system are more concerned about generating power than protecting against the flood. 

"We have no capacity for storing water like some reservoirs, so the Corps tells us what's coming down river, and we pass down that amount of flow," said Ameren Plant Manager Larry Weiman. "When we have flooding like this, we have no way of keeping any control over the river. It's just running. Water is high enough we're not even operating our plant at the present time." 

Weiman said Ameren is "shut down like the rest of the city," and some employees are walking across the dam to get to work from Illinois while they can't access the bridge. 

The Corps of Engineers does provide flood assistance to communities when it's requested by the state. Iowa requested the Corps provide Davenport with a HESCO technical adviser and other support while constructing its new wall, said Sarah Jones, with the Emergency Management Division. 

Jason Smith, a program manager with the Corps in Rock Island, said to protect against major flood events, communities are tasked with moving assets out of the flood zone and putting up barriers. The Corps steps in when the state requests it.

But he thinks the Corps and stakeholders should be doing more to respond to major flooding along the Upper Mississippi River. As flooding becomes more common, Smith is working on a project to create a comprehensive regional flood risk management strategy, which already exists for the Lower Mississippi, he said. 

The study, he said, will focus on "where the water would go during these large events and who is going to take that water," a system the lower part of the Mississippi has in place. Smith said the holistic approach also would explore ponds and reservoirs for storing water, as well as agriculture and urban land management practices. 

"Having a comprehensive plan for the watershed would help folks identify the highest priority items to be completed within the watershed," he said. "The highest priority would be focused on flood risk management, but also navigation, water quality, habitat and ecosystem. The stakeholders would understand the trade-offs, and we'd advance the highest priority items in order to create a more resilient watershed." 

While opinions differ on what steps need to be taken to prepare and manage flooding, many argued cities are struggling to keep up with flooding of this frequency and magnitude, and more needs to be done. 

"Out of our 10 highest crests, we've had around eight of those since 2008," Ferneau said. "I've been here eight years, and we've dealt with flooding around five of those years. We're asking these HESCOs to do things on a river that's acting differently than it has in the past." 

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