Why is there a barge under U.S. 278 to Hilton Head? What we know
Drivers on the U.S. 278 bridge to Hilton Head Island may spot a strange-looking vessel floating in Mackay Creek over the next several weeks.
As part of the design phase of the U.S. 278 bridge replacement project, a barge will float in the creek for the next few weeks, a development the town says will have no impact on traffic.
The barge, brought in as part of the geotechnical exploration phase of the U.S. 278 replacement project, arrived in the Hilton Head waterway earlier this week.
What is a geotechnical exploration?
According to an article by CTL Engineering, a consulting engineering firm that specializes in environmental and geotechnical testing, the purpose of a geotechnical investigation is to understand what’s beneath the surface of a site before something gets built on it.
Workers drill holes into the ground to collect samples of soil and look for signs of rocks that could get in the way of construction. They also examine the soil, to ensure it’s strong enough to support the structure, according to CTL Engineering.
What to know about the project
The U.S. 278 bridge connecting Hilton Head Island to the mainland is actually four separate bridges: two over Mackay Creek and two over Skull Creek.
The eastbound bridge over Mackay Creek was given “poor” ratings in a recent federal study, according to previous Island Packet reporting.
A single, new bridge will replace the two eastbound bridges over both creeks, under a joint proposal by the South Carolina Department of Transportation and Beaufort County.
Details of the project are posted to the SCDOT-run website, scdot278bridgereplacement.com.
The new, wider bridge will be striped for two lanes, but will have full shoulders on both sides to improve emergency response and allow for more lanes in the future, according to the SCDOT website.
A ramp will be constructed to improve access to Pinckney Island and the C.C. Haigh Jr. Boat Landing. A local access road and bridge will maintain access to Hog Island and Mariner’s Cove.
Construction of the new bridge is scheduled to begin in early 2028, according to the website.
The project won’t include traffic improvements on Hilton Head Island. Bicycle and pedestrian infrastructure also won’t be included in the new bridge.
This story was originally published March 21, 2026 at 11:24 AM.
