Rapidan Dam before-and-after 'partial failure' seen on satellite

Rapidan Dam before and after satellite images

Credit: Maxar Technologies via Storyful. Satellite imagery shows the Rapidan Dam on south central Minnesota’s Blue Earth River before and after the dam experienced a partial failure.

MANKATO, Minn. (FOX 9) - Satellite images show the before and after view of the Rapidan Dam, which has been a focal point of Minnesota flooding this week after the dam suffered a partial failure. Maxar Technologies captured before photos dated September 6, 2011 and June 26, 2024 after the incident.

Concerns about bridge as erosion worsens

Blue Earth County officials said Wednesday there has been a "dramatic" shift that has seen the river cut deeper into the west bank of the river. As a result, a neighboring house that was teetering on the edge of the bank has now fallen in entirely. Officials say there is now concern about the Glacier Road Bridge, which runs over the Blue Earth River just south of the dam.

Concerns over bridge near Rapidan Dam

Blue Earth County officials say they are concerned about the bridge near the Rapidan Dam after the dam failed earlier this week.

"There is currently little to no flow through the gates of the dam as the majority of the flow is going around the west side of the dam," officials write. "Although the water flow has slowed slightly, the water is still flowing at a rate that inhibits emergency mitigation strategies. The focus has shifted from the dam to the bridge given the recent erosion."

County officials say they are continuing to monitor the situation with help from state and federal partners. But, each day brings continued amazement at how much more land is carved away.

"I can’t believe how much bank is gone," said Tom Kispert of Mankato.

The canyon created by the Blue Earth River around the Rapidan Dam is now about as wide as the dam it bypassed, and a favorite landscape is forever changed, if not lost.

"It was just nice to come out here and stand on top of the dam. You feel like you were in... not in Minnesota, you know," Kispert reflected.

This is how it looked before the floods, and this is how it looked a couple of days ago. So much has been lost so quickly, and now it’s gotten even wider.

The water level is dramatically down because the erosion is so extensive, exposing the bottoms of the supports under the bridge next to the dam. This is a huge concern, which is why no one is now allowed on the bridge – not first responders, not even engineers who’ve used it to drop gauges into the river.

At the base of the bridge, what was a city park is now just a void in the earth. The playground has already gone into the river. Crews removed the park pavilion to avoid adding even more debris to the floodwaters. A couple of days ago, it was a good fifty yards from the edge.

"And it’s hard to fathom, too, that the last time I was at the Dam Store I didn’t think this is the last time I’m going to be here. This is the last time I’m going to stand on the dam. This is the last time we’re going to have the kids running around at the park. You don’t think like that," Stacy Fisher added.

Now, the edge creeps ever closer to the historic Dam Store, after claiming the family’s home Tuesday night. The ground is too unstable to do anything to try to save the store itself. But behind it, crews removed an old mobile home, just in case it gets that far. Hopes remain that the store survives, but that’s far from certain.

"And the store... it’s unfortunate. Had a lot of good pie there. It was a great place to go," Kispert lamented.

Family watches as house falls into Blue Earth River

The worst outcome from the Rapidan Dam’s partial failure has arrived.

The Hruska family watched their home fall into the Blue Earth River Tuesday night and that might not be the last of their losses. It’s a waiting game now to see if their store — sitting there for more than 100 years now — will also fall in.

House falls into river at Rapidan Dam

Credit: AW Aerial. Video shows a white house fall into the Blue Earth River at the Rapidan Dam in south central Minnesota.

The house and the dam store stood along the river for more than 100 years. The business and the pies have been synonymous with the Hruska family since the 1970s.

But now the store stands alone and maybe not for long. Engineers and Blue Earth County leaders are worried the erosion could soon take out the bridge just south of the dam. And losing the store now seems inevitable.

If the store does not fall into the river, the family is hoping they can pick it up and move it to another location and get the business up and running again. They have started a GoFundMe page to do that and to rebuild the family home.

Timeline of Rapidan Dam emergency

Blue Earth County Public Works and Emergency Management are continuously monitoring the dam. Routine monitoring occurred Saturday, Sunday and remains ongoing.

On Sunday evening, June 23, the dam exhibited high flows and additional debris, but still displayed adequate capacity.

Around 1:30 a.m. on Monday, June 24, notice was issued that there was water overlapping the dam. Around 3 a.m., notifications were sent to regulatory agencies per requirements of the dam Emergency Action Plan.

As flows peaked on Monday, there was partial failure of the west abutment, resulted in the washing away of an Xcel Energy substation causing power outages. The term "imminent threat" was used as outlined in the the County’s Emergency Action Plan.