The latest estimate on the completion of the Mark Clark Expressway across Johns and James Islands is $556 million, according to Ronald Mitchum, executive director of the Berkeley-Charleston-Dorchester Council of Governments.

That’s up $67 million from the previous estimate of $489 million.

Mitchum made the announcement at the group’s 44-member Charleston Area Transportation Study Policy Committee meeting today. He said the South Carolina Department of Transportation had increased the estimate as part its consideration of moving forward with the project.

The DOT needed an updated estimate of the cost of the project, and needs to know that funding has been identified before it would move forward, Mitchum said.

Charleston County Council in January gave up control of the long-stalled Interstate 526 project on Johns and James islands. Members voted 7-2 in favor of turning over the project to the DOT, but it remains unclear whether the road will be finished.

While the vote freed the county of having to pay back more than $11 million already spent on the project, it removes it from local control.

In the spring of 2011, County Council voted not to build the I-526 project because the SCDOT’s recommended route had little support. The group backtracked on that decision after the state bank declared the county in default and ordered it to repay the $11 million. The project has been in limbo since.

Read more in Tuesday’s editions of The Post and Courier