Washington County plans new box culvert on 128th Place

An old deteriorating box culvert on 128th Place near Wellman is going to be replaced later this year.

At Tuesday's Washington County Board of Supervisors meeting, County Engineer Jacob Thorius got the go-ahead to advertise for bids for the project.

Thorius said that bids will be opened on April 12, with the plan to examine the bids and have a recommendation for the board at its April 13 meeting.

The culvert is on 128th Place, just north of Highway 22, about a mile west of Wellman.

Last week, the board authorized the purchase of additional right of way for the project.

'In June 2019, a hole developed on the north side of that structure,” Thorius said at that meeting. 'The stream bed has been lowered from the inlet of the culvert, so the flow line of the stream is lower than the flow line of the box.

'That has created some scouring issues and some undermining issues with water going around the structure.”

He said the existing culvert cannot be used with the flow line being at two different elevations.

'We need to replace the structure,” Thorius said.

Another issue is that, at the current culvert, the stream has a horseshoe bend, making a couple of 90-degree turns.

'Water does not like to go in 90-degree turns,” he said, added that the turns contribute to the erosion around the culvert.

The new culvert will be installed south of the current one so the water can flow straight through.

Thorius said that the new culvert will be a 10-foot-by-5-foot, 48-foot long box culvert with a 32-foot long flume 'to help minimize some of the scour erosion.”

'Construction will be this year,” Thorius said. 'Ideally, there would be construction sometime this summer or as late as early fall.”