ANNAPOLIS, Md. (AP) — The National Transportation Safety Board is preparing to cast a decisive vote regarding the causes behind last year’s catastrophic container ship collision with Baltimore’s Francis Scott Key Bridge, an incident that tragically resulted in the deaths of six construction workers.

This vote, set for Tuesday, follows a significant announcement by Maryland officials who have recently revised the replacement cost for the bridge, more than doubling the estimate and extending the timeline by two years, now projecting completion in 2030. The adjusted cost is anticipated to range from $4.3 billion to $5.2 billion, a stark increase from the earlier estimate of approximately $1.9 billion.

Governor Wes Moore noted on Monday that the initial cost and schedule projections were made within a mere two weeks following the bridge collapse in March 2024.

“Since that time, we’ve faced deteriorating national economic conditions and rising material costs,” Moore, a Democrat, explained. “Increased expenses are also due to federal design and resilience standards, which are beyond our state’s discretionary control.”

The board will convene in Washington to determine a probable cause for the incident, issue safety recommendations, and consider any updates to a previous report.

Investigators previously discovered a loose cable that could have caused electrical issues on the cargo ship called the Dali, which lost power and veered off course before striking the bridge, according to documents released last year by the NTSB.

When disconnected, the problematic cable triggered an electrical blackout on the ship similar to what happened as it approached the bridge on March 26, 2024, according to the previously released documents by the NTSB.

The Dali was leaving Baltimore bound for Sri Lanka when its steering failed because of the power loss. The 947-foot (289-meter) cargo ship then crashed into a supporting column of the bridge about 1:30 a.m., causing the bridge to collapse into the Patapsco River.

Safety investigators released a preliminary report last year that documented a series of power issues on the ship before and after its departure from Baltimore.

Records released by the NTSB after that preliminary report said the Dali first experienced loss of power when it was still docked in Baltimore. That was after a crew member mistakenly closed an exhaust damper while conducting maintenance, causing one of the ship’s diesel engines to stall, according to the earlier report. Crew members then made changes to the ship’s electrical configuration, switching from one transformer and breaker system — which had been in use for several months — to a second that was active upon its departure.

That second transformer and breaker system is where investigators found the loose cable, according to investigative reports.

Engineers from Hyundai, the manufacturer of the ship’s electrical system, said the loose cable could create an open circuit and cause a breaker to open, according to a 41-page report detailing tests completed on the Dali in the weeks after the collapse. The engineers disconnected the cable as part of a simulation, which resulted in a blackout on the ship.

Six men on a road crew, who were filling potholes during an overnight shift, fell to their deaths when the bridge collapsed. The collapse snarled commercial shipping traffic through the Port of Baltimore for months before the channel was fully opened that June.

The NTSB has criticized the Maryland Transportation Authority for failing to address the bridge’s vulnerability to ship strikes — despite major changes in maritime shipping since it opened to traffic in 1977. The board has called on other bridge owners to learn from the example.

The bridge, a longstanding Baltimore landmark, was a vital piece of transportation infrastructure that allowed drivers to easily bypass downtown. The original 1.6-mile (2.6-kilometer) steel span took five years to construct and opened to traffic in 1977. It was particularly important for the city’s port operations.

Crews have been working on knocking down remaining spans of the bridge, a process that began in July.