Star Tribune
What we know about the Rapidan Dam on the Blue Earth River
The Rapidan Dam near Mankato is no longer in danger of “imminent failure” but the 114-year-old structure on the Blue Earth River was still battered by the raging water that slammed debris and sediment into it.
State officials on Tuesday said they expect the Rapidan Dam to survive the deluge that’s soaked much of Minnesota for the last few days.
Here’s everything to know about the dam that’s been endangered by catastrophic flooding in southern Minnesota.
Where is the dam?
Rapidan Dam is about 6 miles southwest of Mankato as the crow flies on the Blue Earth River. It was originally built to provide power to the city — the dam doubled the capacity of Mankato’s power system when it was first erected.
When was it built?
The Rapidan Dam was built in 1910. The facility was operated back then by the Northern States Power Co., according to the Blue Earth County Historical Society, and was constructed using a novel method at the time. Builders used hollow reinforced concrete to increase the structure’s durability.
In 1970, Northern States Power (now part of Xcel Energy) transferred ownership of the dam to Blue Earth County. That same year, the unincorporated community of Rapidan opted to skip the Fourth of July, instead celebrating Rapidan Dam Days four days earlier so that Minnesotans from neighboring communities could come and watch the fireworks.
Two years later, the Blue Earth County board ruled that the dam should either be destroyed or rebuilt because it would cause “considerable damage” to the surrounding area if it collapsed. The dam was one of the first facilities to be rebuilt with funding from the Public Utility Regulatory Policies Act of 1978, according to the historical society.
The Rapidan Dam is 87 feet tall and 475 feet wide
What happens to Mankato if the dam collapses?
Not much. Rapidan Dam hasn’t provided electricity to the city for years — a 2019 flood damaged the facility so badly that county officials began to assess whether it was worth repairing enough so that it could generate electricity again. A 2021 study estimated repairs at $15 million and removal at $82 million.
County officials determined the profit they could make on whatever electricity the dam would generate was not worth the investment. Last year, they initiated the process of handing the dam’s operations over to the federal government.
The National Inventory of Dams has determined the dam poses a “significant” hazard potential for anyone working on the structure or people and wildlife downstream.
Still, the dam doesn’t “hold back a significant amount of water,” officials said Tuesday morning.
Since the 2019 flood, the Blue Earth River has fully flowed through the Rapidan Dam. That storm sent 32,500 cubic feet of water through the structure every second. At its peak, the water flowed at 34,800 feet per second during the most recent storm, officials said.
State officials projected that a water flow of 42,000 cubic feet per second would make the water in the Blue Earth River rise about 2 feet within two miles downstream. A larger threat, officials said, looms in the built-up sediment that would be unleashed downstream if the dam collapses.
Is this the largest flood to hit the Rapidan Dam?
No. Back in 1965, officials say, a 500-year flood sent more than 43,000 cubic feet of water per second toward the structure.
The contents of a suspicious package that caused an evacuation of the Minnesota Secretary of State’s office has been deemed non-hazardous.
The office was evacuated Friday after a package arrived there with the return address of “United States Traitor Elimination Army.”
The white powder inside the package was tested by the Minnesota Department of Health and the U.S. Postal Inspection Service, and both concluded it was not hazardous, Secretary of State Steve Simon’s office said Saturday.
In a statement, Simon said: “We are thankful for the quick response by our law enforcement partners to ensure the staff members working in our office were safe. We are also grateful to the Minnesota Department of Health, which completed the initial analysis late into the evening on September 27.”
The Health Department is continuing to run tests, Simon’s office said, and the incident is being investigated by the FBI, postal inspectors and the State Patrol.
Last week, offices in 15 other states received similar packages that also contained a mysterious white powder. Those incidents remain under investigation.
The Secretary of State’s Office has not released details about the size or appearance of the suspect package.
Four Twin Cities residents traveling with a church group, including one who was pregnant, are dead after a four-vehicle crash in central Utah.
A Utah resident riding an all-terrain vehicle was also killed in the chain-reaction accident, which occurred Thursday near the city of Price, according to the Utah Highway Patrol.
The incident began when an SUV pulled into the path of a truck pulling two trailers. The truck driver swerved to avoid the SUV but lost control, crossed the median and hit a Nissan Rogue driving in the opposite lane.
The people in the Nissan were two couples from the Twin Cities, and all four were killed on impact, said Sgt. Chris Pugliese with the Utah Highway Patrol.
“It was a very violent crash,” he said.
The victims were Sang Her, 56, and Lee Thao, 38, both of Brooklyn Center, and Bee Moua, 26, and Mai Lor, 25, both of St. Paul. One of the two women killed was pregnant, Pugliese said.
KSL-TV in Salt Lake City reported that Lor was pregnant and that she and Moua were married earlier this year.
The four Minnesotans were traveling with a church group, which was in another car and escaped the accident. Members of the church group told authorities that the four victims were traveling from Moab to Salt Lake City. Pugliese said they were planning to fly back to the Twin Cities that night.
Two adults and two juveniles were rescued Saturday from a capsized duck hunting boat in west central Minnesota.
All four were able to hold onto the boat after it overturned around 6 a.m. on Bird Lake in Osakis Township, according to the Douglas County Sheriff’s Office, which dispatched a water patrol boat and an airboat to scene.
The four were having a difficult time staying afloat because their waders had filled with water, the sheriff’s office said in a statement. They were treated on the scene for hypothermia exposure.
None of the four were wearing life jackets, and there were not enough life jackets on hand for all the boat’s occupants, the sheriff’s office said.
