OIG Issues Advisory Regarding the May 2021 Roseland Pumping Station Failure

The City of Chicago Office of Inspector General (OIG) has concluded an inquiry into the causes of the May 6, 2021, equipment failure at the Roseland Pumping Station (RPS), which caused pressure in the water main to drop, requiring the Department of Water Management (DWM) to issue a 24-hour water-boil order for much of the 19th Ward. OIG’s inquiry––initiated at aldermanic request––concluded that the incident was due to the failure of DWM’s rental Uninterruptible Power Supply (UPS), an electrical component that sits between incoming utility power and certain critical equipment and supports the downstream equipment by keeping it appropriately energized. The City’s UPS had been in place since 2018 and, incidentally, was scheduled for maintenance the following month. Further, on May 25, 2021, failure of the same type of equipment caused a second power outage at the facility which did not result in a boil order but exacerbated concerns about the facility.

OIG examined the issues at RPS, interviewing a City vendor and City and ComEd officials and reviewing emails and records. OIG found that the UPS update from a lead-acid battery system in favor of a UPS with a lithium-ion battery had stalled and was taking longer than expected. While the City experienced delays in identifying and effecting a permanent solution, the lead-acid batteries for the rental UPS unit had likely degraded, possibly hastened due to high temperatures in the facility (according to a City contractor familiar with the equipment). These issues gave way to the May 6, 2021, system failure and resulting boil order, when shortly after 8 a.m., RPS experienced a power outage. The facility’s pumps and generators shut down, but there was no voltage loss from any of the utility’s four feeder lines into RPS. City officials said that all four lines into RPS experienced a voltage sag and that it may have been the result of work being performed by or a loss of power from ComEd, while ComEd maintained that there was no voltage loss. In order to mitigate the safety risks, OIG suggested that DWM replace the failed UPS system immediately, procure a unit that uses lithium-ion batteries, and no longer rely on rental UPS units.

DWM issued a response in which it disagreed with OIG’s conclusion and stated that ComEd was to blame for the electrical failures––this was in spite of a City contractor specializing in electrical equipment having determined that “it was impossible to tell if ComEd’s voltage sag and phase imbalance caused the damage to the UPS or if the UPS was not functioning prior to the May 6th event.” DWM also stated that it has taken numerous actions to prevent the recurrence of the events of May 2021, such as initiating a capital project to evaluate the computer programming within the Program Logic Controllers (which control uninterrupted power supplies at all facilities); evaluating the different battery types for future UPS usage; and initiating the move of UPS maintenance logs to a digital workorder management system.

“The Department of Water Management has offered its assurance that the safety of Chicago’s potable water supply is its highest priority. But the issues that occurred at the Roseland Pumping Station, resulting in a 24-hour water-boil order, were consequential and concerning of a magnitude that suggests a need for better alignment of DWM’s actions and operations with its stated priorities. Community members have expressed concerns for years that their neighborhoods lack resources and that repairs to infrastructure tend to either go ignored or forgotten,” said Inspector General Joe Ferguson. “A system as important as an uninterruptible power supply––which supports energy for essential equipment providing a critical service to all residents and businesses––was supposed to be replaced years ago, but was not in this instance. In the immediate aftermath, all that disconcerted residents got was public, accusatory finger-pointing. We appreciate that there may be continuing grounds for differences of opinion regarding causation and responsibility, but hope that the information developed by our inquiry lends greater insight to officials working on the fixes and to the public they serve. OIG is reassured and fully anticipates that DWM will continue to move swiftly, hold itself accountable at a level that the importance of this function merits, and optimally ensure that Chicagoans are not put at risk again.”

The advisory, including DWM’s response, can be found on OIG’s website

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The mission of the independent and non-partisan City of Chicago Office of Inspector General (OIG) is to promote economy, effectiveness, efficiency, and integrity by identifying corruption, waste, and mismanagement in City government. OIG is a watchdog for the taxpayers of the City and has jurisdiction to conduct investigations and audits into most aspects of City government. If you see corruption, fraud, or waste of any kind, we need to hear from you. For more information, visit our website at: www.igchicago.org.