CHARLESTON, S.C. (AP) - Interstate 73, the Carolina Bays Parkway and the Mark Clark Expressway are among projects that could receive money if Congress approves a bill giving South Carolina $1.6 billion more for highways, officials said Monday.

The bill would provide $375 billion for highways and transportation nationwide for six years. With the increase, South Carolina's share would be $4.42 billion.

U.S. Rep. Tom Petri, R-Wis. and chairman of the House Highways and Transit Subcommittee; and U.S. Rep. John Boozman, R-Ark. and a member of the House Committee on Transportation and Infrastructure, visited Charleston on Monday to learn about the state's highway needs.

South Carolina U.S. Reps. Henry Brown and Jim DeMint, both Republicans, joined the two as they briefed local officials on the proposed bill expected to go to the full House next month. Petri is visiting 10 communities nationwide.

"It's a real coup for us to have him here," said Brown, adding that new roads on the coast are vital to tourism. "We cannot afford to simply maintain the current transportation infrastructure," he said.

The coast is the heart of the state's $15 billion tourism industry.

"The coastline of South Carolina is a national treasure. The infrastructure we build serves the entire country," DeMint said.

Charleston Mayor Joseph P. Riley Jr. said road costs are higher along the shore because of the need to build bridges along coastal rivers, marshes and creeks.

Elizabeth Mabry, executive director of the state Department of Transportation, said the state is working simultaneously on Interstate 73, which will link the Grand Strand with North Carolina, and on the unfinished Carolina Bays Parkway.

"We are working on all of them parallel," she said. "The Carolina Bays project is further along. It has the permits. It has the right of ways in many situations. It can go faster."

Mabry said planning for I-73 is not as far along and an exact route has not been decided. The cost to build the interstate in South Carolina has been pegged at as much as $1 billion, although she cautioned that was only an estimate.

Petri said the transportation bill includes more money for new road projects nationwide. To pay to simply maintain the nation's current infrastructure would be about $260 billion, he said.

He said the Transportation Committee does not have jurisdiction to designate money to pay for the construction; the panel helps set priorities for the funding. However, he noted there are a variety of possible sources of money to pay for highways, including normal economic growth or indexing the federal gas tax to the rate of inflation.