The MTA Inspector General’s office found “serious gaps” in the transit authority’s maintenance and oversight of its substations in a new audit the agency watchdog released Thursday that was sparked by a 2024 explosion at one of the essential power conversion facilities.
The audit found that MTA NYC Transit’s Substations Group did not conduct 19% of required maintenance checks at the facilities during the year of the explosion. The incident occurred at the State Street substation and caused a power outage that stranded over 4,000 riders on trains in Downtown Brooklyn.
The OIG’s findings were gleaned from visits to 16 of NYC Transit’s over 200 substations as well as reviews of maintenance records and interviews with Substation Group employees.
“The Brooklyn substation explosion exposed serious gaps in maintenance and oversight that could put the public and NYC Transit employees at risk,” MTA Inspector General Daniel Cort said in a statement.
Substations are an essential piece of running the subway system, as they convert high-voltage electricity from the grid into the lower voltage form needed to power trains via the third rail. The power facilities are one of many aging parts of the over-century-old subway system that the MTA is working to update in its current capital plan.
During substation maintenance checks, known as “field maintenance,” Substation Group employees inspect and rehab the equipment as needed. Without the inspections, the machinery is at greater risk of failure, which could then impact subway operations and cause safety hazards.
The audit notes that NYC Transit did not complete 12 of 23 maintenance assignments at the State Street substation prior to the blast, which sent flames through a subway grate, but did not cause any injuries. However, according to the audit, NYC Transit’s own internal investigation of the explosion found it was caused by damage to copper tubing inside one of the substation’s transformers that could not be detected through visual inspections.
“Because the copper tubing is located inside the transformer, it was not accessible for visual inspections, and the split went undetected,” the audit reads.
The OIG did also ding the MTA for directing an assistant chief was trained as a carpenter to conduct the review of the incident rather than an electrician.
NYC Transit President Demetrius Crichlow responded to the audit by noting that the MTA has rehabilitated 30 substations since the 2024 incident. He said the agency also restructured NYC Transit’s Power Division, which previously oversaw both its power and signal systems, to separate oversight of the two.
“Missed inspections of power substations are unacceptable and leadership of the Power Division has been restructured — splitting oversight of power and signals — to focus on improving maintenance practices and upgrading critical infrastructure,” Crichlow said in a statement. “Since the matters of two years ago, 30 substations have been rehabilitated, in addition to a planned $3 billion investment in new power systems, all providing relief from challenges of maintaining century-old infrastructure.”
The OIG report also notes that NYC Transit improved its substation maintenance rate between 2024 and 2025, completing 90% of required checks last year, roughly 10% more than the previous one.
“NYC Transit’s recent steps to strengthen substation oversight are encouraging, and my office will closely monitor their progress,” Cort said.
The audit also found other issues with how NYC Transit monitors its substation maintenance and safety.
Among those findings was that substation workers were not wearing required personal protective equipment, which must meet National Fire Protection Agency standards, while on the job. The safety gear is necessary to protect employees from hazards, including severe burns and even the risk of death, associated with working with high voltage electicity.
Furthermore, auditors found that substation employees ignored fire alarm “trouble” signals — alerts showing the alarms are not functioning properly — at the six locations they visited that are equipped with such systems.
