CONWAY — Most of the residents of the Pee Dee region who attended a public meeting on the proposed I-73 expressway said it should be built along existing highway corridors.

The interstate, which will cost an estimated $2 billion in South Carolina, is planned to one day extend from Michigan to the Grand Strand.

Highway planners are studying 2,200 square miles in four counties — Marlboro, Dillon, Marion and Horry — as they consider routes for the expressway in South Carolina.

About 150 people turned out Tuesday for the meeting.

They discussed one possible corridor along S.C. 38 to U.S. 501 and then S.C. 22. Another would be along S.C. 9.

Two area conservation groups have endorsed the S.C. 38-U.S. 501 corridor.

The project will move more quickly and cause less environmental damage if existing corridors are used and small towns are bypassed, supporters say.

The South Carolina Coastal Conservation League supports the S.C. 38-U.S. 501 area, in part because there are not a lot of people living along the route.