City digs into causes of flume collapse

Digging could begin today on North Main Street to begin repairs to Shelbyville's underground storm water flume, and while the results of core drilling won't be known for a week or more, it may shed light into the reasons behind the collapse.

Public Works director Mark Clanton said Wednesday that drill was finished Tuesday -- but the method will only enable them to tell what happened underground around the flume, not directly pinpoint the cause.

"What they'll be determining is if there was a cavity that came out, if all the material washed away from around it like the speculation is," Clanton said.

As for the digging work, that will begin today or Friday if all goes according to plan, Clanton said, but first, the undamaged parts of the flume must be "shored up" so it will not be damaged when excavation work begins.

City manager Ed Craig said a pre-construction meeting was held yesterday with Contech, the firm that manufactures the large pipes; the engineer working with the company to determine the cause of the failure; and Clanton Excavating.

A total of eight core samples were taken and it will take up to two weeks for engineers to complete an analysis and give the city a report into what they found.

Clanton said the results would tell the city what "the contributing factor" may have been, but they will not know the exact cause until digging is done and the flume is pulled out of the ground.

However, Clanton said some evidence was discovered Tuesday that may help them understand what contributed to the collapse of the flume.

Speculation over the cause of the collapse has had many looking at recent work done for Shelbyville Power, Water and Sewerage System.

The work that began last November involved re-laying a sewer line starting beside Shelbyville Animal Clinic, engineer John Freeman of the utility said at the time.

The line was laid eastward under North Brittain Street and runs to Madison Street, where a directional bore went under the main thoroughfare, up to the west side of the old Fix-It Shop. After that, the sewer line crossed Jefferson Street to First Christian Church, where the work ended.

David Crowell of Shelbyville Power said last week that until the utility received an engineering report about the flume, it would be inappropriate for him to comment.