Charleston County’s proposed new contract for the completion of Interstate 526 includes two controversial items: It prevents the city of Charleston from weighing in on the project, and gives sole discretion on construction to the county.

The next step for the extension of the Mark Clark Expressway across James and Johns islands involves updating the project’s three-party contract, known as an Intergovernmental Agreement. In the project’s initial $420 million contract, Charleston County was the project’s sponsor, the DOT was responsible for building the road, and the S.C. Transportation Infrastructure Bank was responsible for paying for it.

But Charleston County now wants more control over building the road. It has completed a revised contract to reflect those changes, to which the DOT would have to agree.

County Council Chairman Teddie Pryor said he doesn’t think eliminating a municipal consent requirement would be a problem for the city of Charleston. “The city’s on board with the project,” he said.

And the county is prepared to accept sole discretion on construction and build the road, he said. If the DOT wants to build it, Pryor said, he’s fine with that. “I just want it to get started,” he said.

But, he said, “I just think that those that are closer to a project can manage the project better.”

In South Carolina, before a state road can be built, the cities and towns through which it passes must approve of the project. More than half of the Mark Clark extension will fall in the city of Charleston, the only city or town through which it will pass. But under the county’s proposal, the city wouldn’t weigh in while the road was under construction, because it would not be a state road.

Charleston Mayor Joe Riley said he thinks the county’s revised contract remains incomplete, and that there still is time for changes to be made if they are necessary.

Riley said that he thinks the city and county have an excellent working relationship. But he would like to see some kind of agreement between the city and the county on I-526. “We may well need something official,” Riley said.

Hernan Pena, the city’s director of traffic and transportation, said city and county have a history of forging agreements on road projects. For instance, he said, the city has agreements with the county on the Bees Ferry Road project, the Harbor View Road project, and on a section of the Glenn McConnell Parkway.

“We anticipate an agreement with the county on the Mark Clark,” Pena said.

Riley also said he’s not concerned about a clause in the county’s proposed contract that would give the county sole discretion over reducing the scope of the project, building it in phases or terminating the project. “That’s boilerplate language,” he said.

Project construction will be governed by a final Environmental Impact Statement, which is a federal document that analyzes the potential impacts of a transportation project, Riley said. That document would prevent drastic changes in the scope of the project, he said.

All of the contractual details for I-526 can be worked out, Riley said. “The county is behind it. The citizens are behind it, and the legislative delegation is behind it.”

DOT commissioners, however, have expressed concerns about Charleston County taking over the project. The DOT commission is scheduled to meet Oct. 17, and Chairman John Edwards has said I-526 will be on the agenda. But, the meeting agenda has not yet been released.

Reach Diane Knich at 937-5491 or on Twitter @dianeknich.