An overloaded generator is to blame for the Halifax sewage treatment plant meltdown, according to an interim report.
City Hall has not released the report to the public, citing legal concerns. But they did offer a summary following an in-camera council meeting Tuesday.
The forensic audit confirms the breakdown of the sewage treatment plant stemmed from a power outage on January 14th. During the outage, two generators were supposed to activate, keeping the plant running.
But when three pumps came back online they overloaded one of the generators, according to the report. The generator then shut down to protect itself from damage.
The five-pump system then shut down and could not be restarted. Worse, the emergency shutdown circuit failed to close the inlet gate. The wet well area quickly flooded with approximately 60 feet of waste water, causing millions of dollars in damage.
The investigation found that no operator intervention could have stopped the breakdown.
Five new pumps have been ordered at a cost of $2 million. The cost will be covered by insurance. The plant itself is not expected to be operational until next spring.
City staff say they will use the forensic audit by CH2M Hill to redesign the plant to guard against future shutdowns.