Sinkhole closes part of West River Parkway; officials stumped on cause

A sinkhole — 6 feet wide and 15 feet deep — has shut down a portion of West River Parkway in downtown Minneapolis and left officials stumped as to a cause.

It formed next to the bicycle path adjacent West River Parkway, near Mills Ruins Park, and was reported Wednesday morning to the customer center of the city's Park and Recreation Board.

The site was assessed by officials but the cause remains unknown.

"Once we understand what exactly occurred, we can make sure the solution doesn't suffer the same occurrence again," said Justin Long, assistant superintendent of environmental stewardship division of the park's board.

In the meantime, the parkway, between Portland Avenue and 4th Avenue North is barricaded, and the bike path closed.

"We're asking patrons to stay away from it," Long said. "It's right on the very edge of the pathway and goes two to three feet underneath the pathway. It's not safe for pedestrians or cyclists."

The road will remain closed until the repairs are done. Detours are posted.

A work plan could be developed Thursday and filling could begin as early as Friday if a cause is determined from data collected from Wednesday's assessment. There's no active city utility in the area and old tunnels that run from the Fuji Ya building to the Stone Arch Bridge were determined to be stable, ruling out those factors, Long said.

The crater's opening is 6 to 7 feet in diameter but widens 10 to 12 feet underground. With the current weather forecast, it could get bigger before it's closed.

"We're hoping it doesn't get any larger," Long said.