UPDATE: Workers plan temporary fix for Bagley Downs sinkhole

Public works crews are dealing with a stormwater-system sinkhole discovered Tuesday morning on a small side road north of East Fourth Plain Boulevard, south of state Highway 500 and west of Andresen Road, in the Bagley Downs neighborhood.

The sinkhole at 6300 N.E. 32nd St. is centered by a manhole cover that fell in, leaving only one side visible near the road surface.

Under the pavement is an older stormwater drywell made up of two large cylinders, one atop the other, said Loretta Callahan, spokeswoman for Vancouver Public Works.

Each cylinder is about 4 feet in diameter and 5 feet tall; they had a pipe leading from them.

“What happened is the top cylinder had slid off the bottom cylinder and had tipped slightly, making the manhole lid fall in and off the top of the drywell,” Callahan said.

The hole around and outside of the cylinders now is only about 3 feet or so deep, since some material washed around it, Callahan said.

Callahan said Chris Marler, public-works supervisor in the Stormwater Operations and Maintenance section, had explained to her what happened.

Capt. Kevin Stromberg with the Vancouver Fire Department said part of the area appears to have “washed away with all the water we’ve gotten the past month.”

The area immediately surrounding the sinkhole was protected by cones to warn drivers away. No one had been reported injured as of Tuesday evening, Stromberg said.

City workers plan to conduct a temporary fix today, filling in the old drywell with rock and patching the asphalt surface, at a cost of less than $1,000, Callahan said.

Later, engineers will design a replacement for the drywell, likely a solid stormwater manhole with piping, Callahan said.

The cost and timing for the replacement hadn’t been determined Tuesday.

John Branton: 360-735-4513 or john.branton@columbian.com.