Galveston's Pelican Island Bridge could collapse as barge that slammed into it and caused oil spill is removed

• Residents using bridge to evacuate one car at a time in case of collapse 
• Barge crashed into bridge Wednesday morning, causing oil spill 
• READ MORE: Barge crashes into Pelican Island Bridge Causeway in Texas 

The already unstable Galveston bridge where a barge crashed Wednesday could collapse or be condemned once the trapped vessel is moved from under it, Texas officials have warned.

Thursday morning, Texas officials called the bridge 'unstable,' but continued to allow residents of Pelican Island to use the overpass to evacuate to the larger Galveston Island, as the connector is the only access route to the mainland.

Law enforcement allowed one car at a time to drive off Pelican Island and into Galveston, a time-consuming process.

Cars are not being allowed to enter the island. 

'My concern is that they are going to deem the bridge unusable, which would not be a surprise,' Galveston County Judge Mark Henry told local station ABC 13.

'It was in bad shape before this accident, and that's going to cause some significant disruptions to Pelican Island.'

Henry added local officials had been trying to replace the bridge for a decade, and it was scheduled to be replaced next year.

'People are going to have no real way to get there and back, and with Texas A&M Galveston being there, that's going to dramatically impact A&M Galveston's ability to deliver education,' Henry explained.

Only about 200 people were on the island at the time of the crash. 

The causeway partially collapsed Wednesday, when the barge rammed it around after 10 a.m. after breaking free from a tow boat.

Aerial shots showed the vessel embedded into the side of the bridge, with part of the train trestle that runs along it having collapsed.  

Two crew members aboard the ship, owned by Martin Petroleum, went overboard but were safely recovered from the water.

The impact resulted in an oil spill that had been contained by the US Coast Guard by Thursday morning.

Officials closed down the Gulf Intracoastal Waterway for six and a half miles, with the closure causing a significant problem for maritime traffic along the Texas coast. 

Henry told the outlet that the collision caused vacuum oil to spill from the barge, which has a capacity of 30,000 gallons, it remains unclear how much of it went into the water. 

It comes after the Dali cargo ship collided with the Francis Scott Key Bridge in the Port of Baltimore at the end of March. 

The ship suffered a power outage and crashed into one of the bridge's support columns, causing it to come down and kill six construction workers.

Investigators said he first power outage occurred after a crew member mistakenly closed an exhaust damper, causing one of the ship's diesel engines to stall.

The report provides new details about how the ship's crew addressed the power issues it experienced while still docked in Baltimore. A full investigation could take a year or more, according to the safety board.

The Dali was headed from Baltimore to Sri Lanka, laden with shipping containers and enough supplies for a monthlong voyage.

The Indian and Sri Lankan men on board haven't been permitted to leave since the disaster happened. 

After the initial blackout caused by the closed exhaust damper, investigators say a backup generator automatically came on. 

It continued to run for a short period - until insufficient fuel pressure caused it to kick off again, resulting in a second blackout.

That's when crew members made changes to the ship's electrical configuration, switching from one transformer and breaker system that had been in use for several months to another that was active upon its departure, according to the report.

Investigators stopped short of drawing a direct line between those earlier power issues and the blackout that ultimately caused the bridge collapse.

The safety board launched its investigation almost immediately after the collapse, which sent six members of a roadwork crew plunging to their deaths.