Last month, the U.S. Army Corps of Engineers issued a terse press release saying "historic" walls lining Minnehaha Creek below the famous Minnehaha Falls were in "imminent" danger of collapse and repairs must be undertaken "sooner rather than later." 

The Associated Press distributed the story and the local media, including the Star Tribune and KARE-11, devoted major features to the crumbling "historic" walls, adding that the Corps was ready to contribute $1 million for the project.

Only problem is, there's no solid evidence when the walls were built or who did the work and, according to the Corps' own archeologist, Brad Perkl, there's no basis for saying they're "historic" as trumpeted in the Corps' press release and other documents.

The Corps' May 5 press release accompanied a $226,000 environmental assessment that made a strong case that the walls were a "piece of Minnesota history." The Corps said the walls were 1930s-era structures built by the Works Progress Administration (WPA), part of Franklin Delano Roosevelt's New Deal to reduce unemployment during the Great Depression. 

Corps lacks evidence
The Minnesota State Office of Historic Preservation agrees that if the walls were built when the Corps said they were, they'd be historic. For something to be designated historic, the state office would formally concur with a letter from the Corps stating the basis for historic designation. But the Corps hasn't sent a letter because it now says it doesn't have the evidence it needs to write one. 

"If we cannot confirm that these walls are historic, we cannot recommend the project," said Tom Crump, project chief in the Corps' St. Paul office. That's because the project would have to compete nationally for funds, and without a historic designation it's unlikely the project would be approved.

State Rep. Jim Davnie, DFL-Minneapolis, was chief House author of a section in a bonding bill passed by the Legislature that approved $2.9 million to advance some 23 projects headed by the Minnehaha Creek Watershed District (MCWD). Davnie said he was told the walls were historic. 

The state money will be combined with $1.6 million from MCWD and another $300,000 from the Minnesota Veterans Home for an overall project of $4.8 million. 

Repair will happen, regardless
Mike Wyatt, a planner with the MCWD, said that historic or not, the walls will be repaired beginning as early as this fall — even if the Corps does not come through with its funding.

"It will only mean that other projects on our list will have to be curtailed or postponed," Wyatt said. "But the walls must be repaired."

Indeed, key parts of the 1,390 feet of walls lining the creek below the falls appear to be in danger of failure. At one point immediately downstream from the falls a section has collapsed into the creek. 

As it is now, the current is often swift over the rapid elevation drop from the falls to a stretch farther downstream that opens into broader valley called "the deer pen" (although no animals are penned there). Without the walls, stream-bank erosion would occur in the narrow gorge, threatening a popular pathway along the creek and also retaining walls and other park structures above. 

The 193-acre park, which is classified as a Historic District, draws some 500,000 visitors annually. It's managed by the Minneapolis Park Board.

There's ample evidence of the area's overall historic significance. 

It's one of the nation's oldest parks, and it's where Minnesota's first parcel of land was platted.  It was a popular tourist attraction in the 1840s and 1850s when "fashionable tour" steamboats would chug up from St. Paul to bring visitors to the park; they'd hike into the falls area on the same footpaths that still run along the creek to the Mississippi River. 

Worldwide fame came in 1853
The falls became world famous when in 1853 Henry Wadsworth Longfellow penned "The Song of Hiawatha" (even though the renowned poet never saw the falls).

Geologically, the falls were once located much farther downstream on the Mississippi River. They migrated up and divided at Minnehaha Creek, with the falls on the main-stem river continuing to migrate up to the present-day falls at St. Anthony — falls now kept in place by concrete.

Take a hike through the Minnehaha Falls area with folks like retired geologist Rudy Hoagberg of Edina and you'll learn about the sandstone and other formations that have been exposed by the retreating falls. Hoagberg will also say that erosion is what rivers and creeks do, without exception. No matter what is done to control erosion, as with the stream-bank walls, in time they'll erode away. 

The waterfall itself has changed notably over the last 100 years or so. A photo from 1895 shows a broad curtain of water that contrasts with the much narrower gusher of today.

Geologists like Hoagberg think in terms of millions of years and have trouble with the concept that things are "historic" after 50 years (the time line used by places like the state's Office of Historic Preservation). 

Besides, he was alive when the now "historic" WPA projects were thriving. "What does that make me?" Hoagberg asked as he enjoyed a fish stew at the Sea Salt restaurant in the park.