Flume repair is on schedule so far

Work progresses on Shelbyville's damaged stormwater flume, with the replacement tube in the ground. Public works director Mark Clanton said everything is on schedule so far. (T-G Photo by Brian Mosely) [Order this photo]

Work on Shelbyville's storm water flume is right on schedule, with the massive steel pipe in the ground and ready for a concrete base.

Despite the threat of wet weather over the past two weeks, work has been running smoothly off of North Main Street, where crews have been busy piecing together the 200 feet of steel that make up the segment replaced after underground flooding apparently caused the flume to collapse in April.

Public works director Mark Clanton said Tuesday that everything with the flume is progressing on schedule.

Crews have laid down the section of tube that replaced the damaged steel and will begin to lay down concrete around the base of the flume for stabilization before adding fill material, Clanton explained.

Clanton says if all goes according to plan, the addition of the fill material would happen by the end of this week or the first of next week.

After that comes the back fill process, which Clanton said could happen as early as this coming weekend or next week.

When that step is complete, then work will begin on getting North Main put back together "and get this thing opened up and get it done."

Digging up the entire region, ripping out the old flume and laying down the new steel section has taken just a little over two weeks, Clanton said.

Clanton also mentioned there have been a number of near misses with summer storms threatening to disrupt work no less than six times, but he said the crews have been lucky, with no major rain stopping the construction.

"It's gone real well," he said.

As for determining the cause of the collapse, Clanton said that "is still being investigated."

On June 5, workers discovered that an old sewer line, which was recently replaced by contractors for Shelbyville Power, Water and Sewer, was still open, which could have caused stormwater runoff to enter the area surrounding the flume.

"It suggests that during the flood event, when there was an awful lot of pressure, that the water came back through the old line and then washed out somewhere underneath the flume," city manager Ed Craig said last week.

Craig added that this was just a theory, but apparently when workers installed the new line, in the course of switching over between the old line and the new line, they installed a shut-off valve, "and it appears the valve (on the old line) was left open," he said.