A section of East River Parkway on the University of Minnesota campus will be closed for the rest of the week following a mudslide that barreled down the bluff toward the Mississippi River on Wednesday morning.
Nobody was injured in the collapse, which took out a 100-foot-wide section of the bluff just north of the Washington Avenue bridge. Engineers with the Minneapolis Park and Recreation Board have yet to determine its cause, but heavy rain is suspected to be a factor.
"We're just worried about the inch and a half, inch of rain that's forecast tonight," Cliff Swenson, director of design and project management for the Park Board, said from the top of the bluff Wednesday afternoon. "We just want to make sure that we're prepared, and we're erring on the side of caution."
University staff alerted the Park Board about the mudslide around 9:30 a.m. Wednesday. A walking trail that runs along the bluff was closed immediately, and the parkway between Washington Avenue and Arlington Street was closed about two and a half hours later, Swenson said. Green Line trains that run along the Washington Avenue bridge were temporarily halted.
The area of the bluff that collapsed stands 10 stories above the Mississippi River. Engineers will use drilling equipment this week to analyze the soil, Swenson said.
"In the last five years, we've had six years' worth of rain," Swenson said. "So we're concerned about groundwater elevation. That may be a culprit here, groundwater causing some oversaturation of soils."
In June 2014, torrential rains caused a mudslide on the western bank of the Mississippi River below the University of Minnesota Medical Center. West River Parkway was closed for more than two years for reconstruction.
Park Board engineers were unsure how much debris collapsed Wednesday, Swenson said. The university buildings nearby remained open.
The aftermath of the mudslide was visible across the river from Bohemian Flats Park. Tree roots at the top of the bluff were exposed. A mound of soil settled at the bottom, and toppled trees lay next to the river.