The owner and operator of a ship that crashed into a Baltimore bridge in March, leaving six dead, will pay the US a $100m settlement.

The US justice department announced on Thursday that Grace Ocean Private Limited and Synergy Marine Private Limited, the Singapore-based corporations that owned and operated the Dali agreed to the $101,980,000 sum, settling a lawsuit over the Francis Scott Key Bridge’s catastrophic collapse.

“Nearly seven months after one of the worst transportation disasters in recent memory, which claimed six lives and caused untold damage, we have reached an important milestone with today’s settlement,” said Benjamin C Mizer, principal deputy associate attorney general.

“This resolution ensures that the costs of the federal government’s cleanup efforts in the Fort McHenry Channel are borne by Grace Ocean and Synergy and not the American taxpayer,” Mizer also said.

The justice department civil claim, filed in September, accused the owner and operator of ignoring electrical problems on the ship. Prosecutors alleged that because the Dali’s mechanical and electrical systems were poorly maintained, the vessel lost power, traveled off course and then struck the bridge.

A large portion of this major road bridge fell into the river, killing half a dozen construction workers. Authorities spent more than $100m to clean up underwater debris and reopen Baltimore’s port.

“This tragedy was entirely avoidable,” the lawsuit said.

The bridge collapse disrupted commercial ship traffic through Baltimore’s port, and the channel did not fully re-open until June.

The Dali was departing Baltimore en route to Sri Lanka when its steering failed from power loss. While police swiftly stopped traffic from driving on to the bridge, likely preventing far more deaths, they were not able to warn the road crew in time.

The construction crew was working overnight to fill potholes on the roadway when the Dali collided with a key support column, propelling them into the water.

The victims’ families have called for stronger worker protections, especially for immigrant laborers. All the victims were Latino immigrants who moved to the US for better-paying work and greater opportunities.

The federal government, which led cleanup efforts, had to remove some 50,000 tons of steel, concrete, and asphalt from the channel, as well as the ship. Federal officials also had to construct temporary channels to help alleviate the blocked waterway.

This settlement does not include money for re-building the Francis Scott Key Bridge. As Maryland built, owned and operated the bridge, state attorneys are pursuing claims for these damages.

The state estimates that rebuilding costs will range between $1.7bn and $1.9bn and that the project should be completed by fall 2028.

Reuters contributed reporting