Closure structures are meant to be erected during threat of a flood to fill the gaps in floodwalls that now exist to allow pedestrians and traffic to pass. When installed, the structure crossing 16th Street stretches 87 feet across the roadway, requiring 500-pound columns about every eight feet to hold up a set of 16 30-pound stop logs. From end to end, including closing off pedestrian pathways, the structure extends nearly 129 feet.

On Tuesday, workers erected and disassembled the closure structure on one side of the street before doing the same on the other, thus allowing traffic to continue on half the roadway. It took about an hour to an hour and a half to erect half of the closure structure, but the number of workers was about three times the workforce the city can expect to assign to the task an actual flood emergency.

That’s because the department will have not just the 16th Street closure but 20 to 22 flood wall gaps that will require closures once the flood protection project is built, Public Works Director Dan Jonasson. Workers will be spread out over those projects. It is estimated there will be about 88 hours of total assembly time.

Practicing the assembly is beneficial in determining how best to go about the process most efficiently.

Jill Schramm/MDN A worker places a stop log in closing off a pedestrian walkway at the flood wall next to 16th Street Southwest Tuesday.

“As we go along, we are going to find things we can streamline and do better,” Jonasson said.

Trainings such as the one Tuesday will be needed annually. In addition to ensuring workers are familiar with the erection and dismantling processes, it is important to regularly check the condition of the materials, Jonasson said.

In addition to assembly of the columns and stop logs, erection of the closure structures requires cleaning the bases built into the roadways and mobilizing the materials and equipment. The columns and aluminum stop logs used as a temporary closure are all housed in a storage building on site near the Water Treatment Plant.

Tuesday’s training was the second of its kind to occur near the Water Treatment Plant. More than 30 city staff participated in training at the end of June for the portion of the floodwall between 12th Street and 8th Avenue Southwest.

In total, 1,720 linear feet of concrete floodwalls are in place on the south side of the Souris River to protect against a 2011-level flood event, plus freeboard. These floodwalls tie into two new temporary roadway closure structures and earthen levees. New lift stations and the adjustment of intake structures at the treatment plant were also part of the project.

This $25 million project represents the first floodwalls and levees built after the 2011 flood. The Hazard Mitigation Grant Program through the Federal Emergency Management Agency provided a 75 percent cost share, with the State of North Dakota’s providing 10 percent and the City of Minot 15 percent. The HMGP-Water Treatment Plant Project is a stand-alone effort to provide long-term protection to the region’s main potable water treatment facility.