ITHACA, N.Y.—A pair of Turblex blower failures at the Ithaca Area Wastewater Treatment Facility, accompanied by severe problems with a primary sludge digester, will cost up to $2 million to repair, expenses approved by the City Administration Committee late last month.
While the issues don’t appear to represent a disruption of service, they do leave the facility significantly short-handed, according to IAWTTF officials and the resolution passed by the City Administration Committee. The failures, according to the resolution, occurred in December and March for the blowers and on March 11-12 for the primary digester.
In a narrative prepared by consultants hired to assess the situation, they called the primary digester’s condition represented an “emergency situation,” that demands “immediate action.” According to the resolution, the repairs necessary include removal of contents, cleaning and inspection, repair of anchoring system, and potentially work on the secondary digester.
The damage to the digester was caused by an overflow that occurred on the aforementioned night of March 11-12, the result of “excessive debris.” It caused the liquid in the tank to surge upward 18 inches, “breaking anchor bolts, mounts and concrete.” The digester cannot “restore reliable digester operations” until the repairs are made.
The repairs to and evaluations of the Turblex blowers will cost, at most, $400,000 (but potentially less), while the repairs to the primary digester were budgeted at around $1.6 million. The facility is the joint responsibility of the City of Ithaca, the Town of Ithaca and the Town of Dryden. The Town of Ithaca will vote on contributing its portion of the repair expenses on May 12.
Asked by City Admin Committee member Graham Kerslick how this could be prevented going forward instead of having to react after a failure, IAWWTF official Scott Gibson said that regular, meticulous cleanings need to be scheduled and paid for, despite the high cost, and that some forensic assessment of the separate issues with the blowers and the primary digester would help as well. He emphasized that he didn’t think there was much blame to go around though.
“We were ready to think about cleaning these things, and it could just be chalked up to that it was time and we should have cleaned it a year or two earlier,” Gibson said. He currently works as the Acting Stormwater Management Officer. “Same with the blowers, we need to do a forensics (…) You wouldn’t clean a digester out, pull the cover off, without looking at the piping and the valving to see if they’re truly clear of debris.”
From the reaction of city officials, it is clear that the failure was a fairly surprising turn of events, particularly since the equipment was so young, at least by industrial machinery standards. That led them to question why Gibson would trust the same company to fix the blowers as had provided them in the first place. He responded, though, that initial analysis of what went wrong with the blowers specifically was that they were often run below their capacity, which ultimately damaged their ability to handle surges in usage.
“If you talked to me a week ago, you’ve got two blowers that died after only seven years of operation, so why would we trust that company for a repair or a factory rebuild? We wouldn’t,” Gibson said, before acknowledging the extenuating circumstances since the machinery was typically run below its capacity. “It’s felt that cavitation surging and a lot of undesirable conditions occurred that could have caused their demise. I think there’s enough evidence to suggest that that is indeed what happened.”
Accommodations can be made, however. Gibson said the machines can be sent to the manufacturer, tested and repaired, and that the company will give them a warranty (there are already two other blowers at the facility that have not failed). Most importantly, he indicated that the machines will also be adjusted so that they do not run below a certain capacity. The one year warranty is only available through the larger analysis and repair package.
“The company’s willing to balance them, they’re looking at speed checks, they’re looking at bench-top operation, they’re going to evaluate every component that went bad, they’re going to replace every component that went bad,” Gibson said. “They’ll ship them back, and we get a one year warranty. We wouldn’t get that if they were just coming in to replace bits and pieces.”
Committee member Laura Lewis then asked if other municipalities had encountered problems with that machinery. Gibson said that was his team’s first thought as well, but that it didn’t seem to be the case.
“If you’re running machinery outside of its comfort zone, you’re asking for problems,” Gibson said, estimating that the machines were probably running under their recommended minimum capacity for 15 hours per day.