‘Derecho’ storm hits Kingsbury County

Damage from storm is widespread, but eastern region hit hardest

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Derecho (duh-RAY-choh), as defined by Wikipedia, is a widespread, long-lived, straight-line windstorm that is associated with a fast-moving group of severe thunderstorms known as a mesoscale convective system (squall line).

The National Weather Service (NWS) classified Thursday’s storm as a derecho. They can cause hurricanic or tornadic-force winds, and they have very unique radar-observed features. While a tornado or hurricane have a “twisted” wind, a derecho will usually involve intense winds flowing in a straight line. Wind speeds can vary along the derecho, and some have been known to span a distance greater than 250 miles wide.

Just after 5:30 p.m. on Thursday, most residents in Kingsbury County could see a line of fast-moving thunderstorms traveling from the south to the northeast at a high rate of speed. The NWS stated the storm was moving at 50 to 70+ miles per hour. The sky was dark and ominous and could have easily been taken from a story line in a Stephen King novel.

The line of storms stretched from eastern South Dakota toward west central Minnesota. In its wake was a path of destruction. Trees were toppled, power poles were either snapped like toothpicks or pushed over. Small sheds rolled around like tumbleweeds, shedding bits of sheet metal as they traveled along. Roofs, shingles, anything the wind could get beneath, were ripped from structures and sent sailing through the air or scooting across the ground, crashing into other structures. Camper trailers and high-profile vehicles were turned on their sides.

Very few residents of Kingsbury County escaped the storm’s destruction without any damage.

THE DAMAGES

The NWS reported that wind speeds associated with the derecho were between 70 and 117 miles per hour. In De Smet, the Wilder Field airport clocked wind speeds at 82 mph that evening.

Damage across the county was more severe on the east side. Arlington was hit especially hard, compared to Lake Preston and De Smet.

While residents were watching the storm roll through and hopefully seeking shelter, law enforcement officers and firefighters were busy watching the storm and giving updates. Seven tornadoes were associated with the storms.

Two of the tornados were categorized as EF2 with winds at 111 to 135 mph. They were in Castlewood and Gary. Four tornados were classified as EF1. Their winds would be 86 to 110 mph, and those were located north of Lake Kampeska, east of Dumont, northeast side of Lake Alice and south and southwest of Webster. The final tornado was a class EF0 with winds at 65-85 mph, and it was located east of Wheaton. All were outside of Kingsbury County.

After the storm pushed through the area, law enforcement officers began patrolling and assessing the damage. It did not take long before most of the first responders in Kingsbury County were busy. Sirens could be heard darting one direction, and another headed in a different direction. Reports are that most injuries were minor, but some required a local emergency room visit. There are now updated reports showing two fatalities associated with Thursday’s storm, but none locally.

In the aftermath of the storms, many residents were without power.

“The eastern half of our service territory was the most affected,” said Kingsbury Electric Cooperative General Manager Evan Buckmiller. “From De Smet west, we did not have any outages. It was all mainly east of Lake Thompson.”

Buckmiller stated that an estimated 60% of their customers lost power, and by Monday morning, 99% of their customers had power restored.

Kingsbury Electric covers most of Kingsbury County except for the incorporated areas and the two southern corners. They maintain 600 miles of electrical lines, with 400 miles of that being above ground. The storm damaged just 12 power poles in their service area.

Out of four substations that Kingsbury Electric utilizes, three substations went off-line.

“Most of our outage time was due to East River Electric having poles broken on the transmission line that feeds our substations,” said Buckmiller.

Power to those substations was restored 28 hours later, on Friday around 9:30 p.m.

The employees of Kingsbury Electric worked Thursday through Monday restoring power. Putting in 12-16 hours a day was common. One tactic that sped up the restoration was tackling all the little problems, while other crews concentrated on restoring the transmission lines to the substations. Once the substations had their power restored Friday night, all the minor problems in the rural areas were already addressed; most customers had their electrical service back on-line.

Otter Tail Power Company, who provides service to Lake Preston, De Smet, Hetland, Erwin and Oldham, reported that an estimated 40% of their customers lost power Thursday. They also had 35 power poles damaged that needed to be replaced. Their service area utilizes 170 miles of electrical lines.

Trees that had fallen across a road were a common concern all over the county. Recent rains had saturated the ground and made the trees easy to blow over, root ball and all. Citizens with chainsaws, tractors and other heavy equipment were soon opening the blocked roads.

Cemeteries were hard hit, especially pine trees. Beautiful rows of tall pine trees now appeared like staggered plantings of trees. Years and years of growth and beauty were destroyed in a matter of minutes.

BACK UP PLANS

Very few residents anticipated a power outage lasting 24+ hours. Shortly after the power went down, you could hear the roar of emergency generators running. At about the same time, the high-pitched whining of chainsaws could be heard as well. Everyone was busy trying to restore some normalcy to their properties and lives.

OBSERVATIONS

Kingsbury County Emergency Manager Cindy Bau was busy all weekend assessing damage across the county. She agrees that Arlington was hit the hardest. The bank on Main Street was destroyed by the winds. By Thursday night, Arlington had their roads cleared of debris, and by Friday at noon, every house had stacks and piles of branches and debris out by the street, waiting for pick up.

Tango Tango, the new communication software the county recently implemented for all the first responder agencies, did what it was designed to do. Communication between the different agencies was improved, and Bau was also able to contact representatives from each agency easily.

NORMALCY

With the dangers over, and the damage assessed, most people had formed a game plan on how to clean up their properties. Driving through the different towns, individuals, families and crews were busy working and cleaning up. They were busy restoring their routine lives the derecho has disrupted just days earlier.

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