Underwater inspections of a pipe and valve at Ashland dam planned
Apr. 1—ASHLAND — Divers will be going underwater at the Ashland Area Municipal Authority reservoir to check a large pipe and a valve as part of a required inspection.
The AAMA board received an update on the long-delayed video inspection at its in-person meeting on Monday.
Project Manager Jennifer M. Kowalonek, of Alfred Benesch & Co., the authority's consulting engineers, said a coordination meeting was held on March 3 with two contractors.
During an inspection last year, a problem with a pipe leading to the valves was found, which required a video inspection by the state Department of Environmental Protection.
The initial video inspection last year showed heavy tuberculation, or the formation of small mounds of corrosion on the inside of iron pipe, which increases resistance to water flow.
About 190 feet into the pipe the camera could not advance due to debris.
That inspection also showed the operations of the upstream valve had a potential issue with the seating of the valve. A video inspection would provide information about how to best address the situation and cleaning of the pipe.
Mobile Dredging & Video Pipe, of Chester, and Progress Marine, of West Chester, will provide the video inspection/disposal removal and the diving services, respectively.
"The work is tentatively scheduled for the week of April 12," Kowalonek said. "In the week prior, the AAMA staff will be switching the raw water source to the 12-inch line and therefore allowing the diving work to commence on the 16-inch line on April 12, with cleaning to commence on the 13th."
After the meeting, Kowalonek said that for the valve and dive work, the authority would not be switching to wells.
"They (the authority) actually have two lines from the reservoir," she said. "They typically use a 16-inch line, but will be using their 12-inch line while work is being completed on the 16-inch line. There should be little or no impact to the water system. ..."
In another section of the report, Kowalonek said that dam consultations on the embankment have not been scheduled.
Benesch has developed the request for proposal, or RFP, for the necessary drilling at the site and has submitted the plan for the work to DEP.
Kowalonek cited DEP backlogs for the delay.
"When we receive agreement from DEP, we intend on sending the RFP to a selected group of drillers," Kowalenek said in her report.
The work is to determine the cause of the seepage coming through the dam breast.
It was discovered about five years ago during the raising of the reservoir breast for managing water overflow, as mandated by DEP.
Since its discovery, there has been no change to the seepage, which appears to be from a water table and not from the reservoir through the dam breast, which has been measured frequently in case of change.
Contact the writer: jusalis@republicanherald.com; 570-628-6023
