The cargo ship Dali crashed into the Francis Scott Key Bridge in March in Baltimore, killing six people and paralysing a major transportation artery for the US Northeast. The US Army Corps of Engineers said a survey on Monday certified the riverbed as safe for transit and said the Fort McHenry Federal Channel had been restored to its original operational dimensions of 213m wide and 15m deep.

The fully operational channel will allow two-way traffic and the ending of the additional safety requirements that were required because of temporary reduced channel width.

The US Army Corps and US Navy salvage and diving supervisor worked to clear Key Bridge wreckage for more than two months before the final piece was removed last week. The Dali was safely moved on May 20.

More than 1,500 individual responders along with 500 specialists from around the world operated a fleet of boats during the operation which involved 56 federal, state, and local agencies.

Surveying and removal of steel at and below the 50m mud-line will continue to ensure future dredging operations are not impacted and wreckage will continue to be transported to Sparrows Point for follow-on processing.

In April, the FBI opened a criminal probe into the collapse. The National Transportation Safety Board said last month the Dali lost electrical power several times before it crashed into the bridge including experiencing a blackout during in-port maintenance and shortly before the crash. Maryland estimates it will cost US$1.7 billion to US$1.9 billion to rebuild the bridge and anticipates completion by fall 2028.