The S.C. Department of Transportation released a graphic Thursday showing the planned Friday-to-Monday morning closing of a northbound entrance ramp to Interstate 77 near Celanese Road in Rock Hill.
Three right lanes of the interstate over the Catawba River also will be closed, the agency said.
All work and lane closures will begin at 10 a.m. Friday and will remain closed until 4 a.m. Monday, DOT officials said Thursday.
The closings are needed so bridge repair work can be done, DOT officials announced Wednesday.
All other nearby I-77 entrance ramps will be open, but motorists are advised to merge to the left lanes.
A routine inspection conducted by the S.C. DOT York Maintenance Division earlier this week showed concrete deteriorating on the bridge deck, the agency said in a prepared statement.
While the bridge is safe for travel, the condition warrants repairs before it worsens, DOT officials said.
The three outside lanes, or right lanes, will be closed at mile marker 81, south of the Cherry Road interchange, to mile marker 83, south of the Sutton Road interchange.
Motorists are advised to expect congestion and to consider alternate routes.