Departments Work Together to Fix Hard to Reach Blockage

November 17, 2011

On October 28th, one of our Wastewater crewmembers identified some discoloration in the water in Pine Creek. Upon further inspection, they found a manhole overflowing 1.07 miles into the woods. Crews backtracked to the blockage point. In order to get to it, they had to navigate around a ravine.

Rocks and other debris collected and clogged that spot in the pipeline, which caused the blockage. Grease, sand, rags and other small items attached themselves to the debris further compounding the issue and almost completely blocking that portion of the pipe.

The Street Division of the Engineering Department assisted by bringing in a four-wheel drive backhoe. In that particular area, the kudzu is 3 feet deep. Utilizing the backhoe, the vegetation was cleared and crews were able to locate the manholes in that pipeline. They had previously utilized a metal detector, but were unable to detect the manholes due to a metal fence that was creating interference.

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Wastewater used the HydroJet power wash apparatus to force water down the pipe while crewmembers listened for the sound of water flow. This was the only way they were able to find the third manhole. Once located, they had to dig it out as dirt and debris had washed down the hill burying it 2-3 feet underground.

This manhole was full and starting to overflow. Crews moved up line to the next manhole, which was empty, alerting them that the blockage was somewhere between the two. They, again, used the power wash apparatus to force enough space to let the flow go downhill. Once drained, Wastewater crews went down into the manhole with a rope, bucket, and shovel. They removed all the debris; twenty 5-gallon buckets of rocks and other material. The process was tedious. They had to pressure wash 50 feet and then pull back and remove debris. This maneuver was repeated at increased distances until the entire line was clear.

Manhole 1 (Overflow) ← 253 ft. → Manhole 2 (Full) ← 400 ft. → Manhole 3 (Clear)

RTJ was gracious enough to allow Wastewater to connect to their irrigation in order to refill the HydroJet truck while power washing the line.

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Wastewater installed a large pipe in the ravine. They are currently building a road across it to continue the cleaning process further up the line to prevent this from happening in the future.

Wastewater wants to thank the Engineering Department and the grounds crew at RTJ for their assistance in resolving the problem. A special thank you goes out to Battalion Commander Whaley for providing gas monitoring equipment to ensure the health, safety, and well-being of our employees while they were down in the manholes.

ADEM was notified and updated on this incident.

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