Emsworth solves stormwater mystery


The mystery as to the cause of storm water backing up with enough force to lift the 200 pound lid off a manhole has been solved, and the emergency repairs have been completed at a high cost to Emsworth Borough.

Heavy rains in June "flagged our attention," said Emsworth Council member Dan Lenz, chair of infrastructure projects and planning. The manhole cover blowing off was dramatic, but perhaps more ominous was the threat that the excess water flowing above-ground near the Emsworth pump station would undermine a portion of Ohio River Boulevard and the Norfolk Southern railroad tracks.

In September, Emsworth Council approved a motion to spend not more than $72,500 to make the necessary emergency repairs to correct the storm water problem. Dennis Flynn, a Gateway engineer who works closely with Emsworth Borough, was to vet the prospective contractors and award the project to the contractor best suited for the repair job. Soli Construction, which has performed a number of municipal sewer projects throughout Allegheny County, was chosen. The work took about a week, and the project was completed on Oct. 13, said Flynn.

The final cost of the repairs, when including the engineering involved as well as the actual repair work, has not yet been tallied.

Originally it was thought that there was likely a break in the pipeline that runs from a manhole along Route 65, travels down the steep hillside, through a metal inlet box, and then continues toward the Ohio River. The possibility that the pipe was merely blocked was also discussed. Camera attempts to diagnose the problem had been unsuccessful.

However, no one had anticipated what was actually found: a second inlet box. And that was the source of the trouble.

The second inlet box, located about 10 feet away from the known metal box, was made of concrete. When the dirt covering it was removed, according to Flynn, a camera was able to travel up the pipe, and found the box to be defective. The second box was connected to the main line incorrectly with plastic pipe. Concrete had been poured into the floor of the box, and that partially blocked the opening. Also, a concrete collar was placed around the juncture between the pipes. The concrete collar had collapsed, entirely blocking the line. Additionally, the inlet pipe was located below the outlet opening.

"It was a problem waiting to happen," said Lenz.

To correct the situation, "Gateway, along with Soli, formulated the repair," said Flynn. The inflow elevation was raised to a point higher than the outflow, and in order to allow for a gradual grade from the connection to the concrete line to the inlet box, a portion of the concrete line was replaced. Finally, the entire new pipe line was concrete-encased, explained Flynn.

According to Lenz, currently there is no paper trail that proves who constructed the problem-causing box. However, circumstances more than suggest that it was installed by Norfolk Southern, Flynn said, as both boxes are located on the railroad's right-of-way property, both boxes appear to have been built at the same time, and the box was surrounded by creosote-covered railroad ties.

Making the repairs was a difficult task technically. The hill is extremely steep and is located on the railroad's right-of-way. In order to work there, the railroad required that a company flagger, usually provided at a cost of $900 per day, be on site to warn of approaching trains. Norfolk Southern waived the cost of the flagger, as well as the nearly $2,000 fee to enter the right-of-way to work on the site. Also, the speed of passing trains was greatly decreased while the project was on-going, according to Lenz.

Additionally, the excavator knew fiber optics lines were somewhere in the area, but their exact location had not been accurately marked. Digging carefully, the Soli Construction operator uncovered a bundle of 10 fiber optic lines belonging to a New Castle company. Had those been damaged, the cost could have been astronomical.

He was a "damn good operator," commented Lenz. He made a level area on which to set the excavator during the project. And as rain had caused the hillside to become quite slippery, when the job was done, in order to get the excavating machine back to the top of the hill, he had to use the bucket as an arm, stab it into the ground, and then pull the excavator upwards while turning the machine's tracks.

In September, Emsworth Council suggested that various methods of seeing reimbursement for the cost of repairs would be sought. According to Flynn, PennDOT has stated that the state is not responsible for any subsurface storm water facilities, and Norfolk Southern has not determined if it has any liability.

The storm water problem has been solved and corrected, but even more expensive repairs are looming for Emsworth in the near future. At the October meeting of council, Lenz warned that about 600 feet of sanitary line pipe should be replaced, at a cost expected to exceed $213,000. That pipeline runs from the pump station up the rock face of the hill and under Marmo Park, then continues up to Huntington Avenue, where the contents are then gravity-fed into a sanitary line.

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