U.S. Route 17 in South Carolina

U.S. Highway 17 (US 17) is a part of the United States Numbered Highway System that runs north–south from Punta Gorda, Florida to Winchester, Virginia. In South Carolina, it is a 221.454 mi major highway that travels near the Atlantic Ocean. Beginning from the Georgia state line at the Savannah River, US 17 enters South Carolina in Jasper County, where it intersects with Interstate 95 (I-95). The route goes through Hardeeville. It merges with I-95 until Point South, then heads east into Beaufort County, through the ACE Basin, and eventually reaches Charleston. There, US 17 crosses the Ashley and Cooper rivers, crossing the Arthur Ravenel Jr. Bridge and becoming a major route through Mount Pleasant. Continuing through the Francis Marion National Forest, it reaches Georgetown. Then it follows the Grand Strand, bypassing Myrtle Beach before entering North Carolina near Calabash.

US 17 predates the Interstate Highway System and remains an alternative to I-95 for local and long-distance travel. The highway offers a more scenic coastal route than I-95's inland path. During hurricane seasons, US 17 serves as an evacuation route for coastal communities, particularly in the Grand Strand regions.

Throughout its route in South Carolina, the highway is commonly called the Coastal Highway. Historically, a portion of US 17 was part of a much longer colonial-era route known as the King's Highway. This historic road stretched from Charleston to Boston, Massachusetts, serving the major colonial cities along the Eastern Seaboard. Additionally, multiple portions of US 17 were part of the Ocean Highway, due to the highway being near the Atlantic Ocean.

Georgia state line to Charleston
US 17 enters into South Carolina in Jasper County as a two-lane road and, within 8 mi, enters Hardeeville, where it becomes a major four-lane freeway configuration. US 17 intersects Interstate 95 (I-95) at exit 5 in Hardeeville and after the intersection with US 321, runs parallel to I-95 until Ridgeland, where it merges with the Interstate at exit 22 until Point South. At Point South, US 17 leaves I-95 at exit 33 and heads eastward into northern Beaufort County, sharing a concurrency with US 21 until Gardens Corner. US 21 splits off to Beaufort while US 17 heads northeast into the ACE Basin and Colleton County. Once in Jacksonboro, the road enters into Charleston County crossing over the Edisto River and regaining a four-lane configuration for the remainder of the state. The road passes through several rural communities as it approaches Charleston from the west. Just before the interchange with I-526, major commercial development starts and continues into the West Ashley neighborhood of Charleston. The route then approaches the Ashley River.

Charleston to Georgetown
In Charleston, US 17 traverses the Ashley River Drawbridges and comes onto the Charleston Peninsula, being routed north of the city's historical areas. The first portion is at-grade and has a few traffic signals for flow purposes. Upon reaching the eastern terminus of I-26, US 17 becomes controlled-access and above grade as it approaches the Cooper River via the Arthur Ravenel Jr. Bridge and the stretch of US 17 in Charleston is infamous among locals for its traffic congestion, especially on weekday mornings.

Upon crossing the river, the highway enters Mount Pleasant at grade and is signalized for several miles up through the second interchange with I-526 and connecting roads to the Isle of Palms and Sullivan's Island. The road leaves the Charleston metropolitan area by entering the Francis Marion National Forest and going through the rural communities of Awendaw and McClellanville on its northeastern journey to Georgetown. US 17 crosses the marsh-lined Santee River as it enters Georgetown County. After going through Georgetown, US 17 crosses eastward over the Waccamaw–Pee Dee river system before making a northward turn along the Grand Strand.

Georgetown to the North Carolina state line
The last component of US 17 runs close to the Atlantic Ocean, beginning at Hobcaw Barony and DeBordieu Colony, passing by Pawleys Island, and going past the Litchfield beaches and Murrells Inlet. It enters Horry County. It passes Garden City, Surfside Beach, and arrives in Myrtle Beach. US 17 splits here between a business route and the standard route, which remains west of the beach and tourist areas served by US 17 Business. The roads rejoin north of the city and continue as US 17 through Atlantic Beach, North Myrtle Beach, and Little River where the South Carolina Welcome Center can be found across from the intersection with SC 179 before crossing into North Carolina. The portions from Murrells Inlet to the state line are quite congested at times, though the soon to be constructed I-73 should assist in alleviating many traffic issues.

History
The route was part of the 1926 approved plan for a national system of highways and appears on the approved map. When first signed, US 17 followed a route that went through Florence and Marion. The original route through South Carolina was 288 mi long.

At the time, U.S. Highways in South Carolina used a dual-numbering system; US 17 was also signed SC 1 from Georgia to Yemassee, SC 30 from Yemassee to Walterboro, SC 6 from Walterboro to Charleston, SC 2 from Charleston to Goose Creek, SC 41 from Goose Creek to Florence, SC 3 from Florence to North Carolina. By 1928, all the dual numbers had been removed except for SC 2. The entire route from Georgia to North Carolina was paved by 1930. At one point, the route from Green Pond to Jacksonboro was SC 32.

In 1931, the route was extended to Punta Gorda.

The early routing was already identified to be shifted to the Kings Highway which would pass through Myrtle Beach and Georgetown; rerouting occurred in 1935.

In 1941, the segment of roadway between the Tullifinny River and Harbor River was widened to four lanes.

In 1947, US 17 was relocated to stay onto king Street and Columbus Street in Charleston.

In 1952, a one-way pair was created in Charleston near the Ashley River Bridge. By 1959, this had been modified again to use Spring Street.

In 1956, US 17 was widened to four lane between Ridgeland and Pocotaligo. That same year, it was widened to four lanes between what is now SC 171 and Downtown Charleston.

In 1961, a second draw span over the Ashley River was opened to traffic, this was done to reduce congestion. This one was officially named the T. Allen Legare Bridge.

In 1963, the segment of roadway between Myrtle Beach and Atlantic Beach was widened to four lanes.

The first tourist welcome center in South Carolina opened in February 1968 on US 17 near Little River.

In December 1968, the segment of roadway in Downtown Charleston was moved off of local streets and onto the Crosstown Expressway.

A segment of US 17 between Ridgeland and Point South once contained two four-lane divided sections. The first is in Coosawhatchie between north of the culvert for Little Bees Creek and north of the bridge over the Coosawhatchie River. From 1971 to 1975, portions of the segment were relocated onto I-95. The divided section in Coosawhatchie remains intact, while the northbound lane near the Tullifinny wetlands was closed, and today is used for a fishing pier, a parking lot of a church, and a private home.

In 1980, the road was widened to four lanes between Awendaw and McLellanville.

In 1981, a bypass of Myrtle Beach was opened, US 17 Business was designated in its former place. it involved constructing new roadway, as well as utilizing existing roadway.

In 1997, US 17 was rerouted to cross the Georgia state line through Savannah, this new segment replaced US 17 Alt. The old route into Georgia was became part of an extended SC 170.

In 2005, the Crosstown Expressway segment concurrent with Lee Street was permanently closed. In its place, a new concurrency with I-26 was created, and a new Meeting Street interchange was also constructed. This was done as part of a project to replace the obsolete Cooper River bridges.

On April 21, 2010, the Crosstown Expressway was renamed the Septa Clark Expressway.

ACE Basin widening project
The widening project addressed a 22-mile segment of the highway stretching from Gardens Corner in Beaufort County to Jacksonboro in Colleton County. This segment of the road, notorious for its high accident rate, was featured on a NBC Dateline special titled America's Most Dangerous Roads. In 1985, the South Carolina Department of Transportation (SCDOT) recognized the need to improve the segment of US 17 due to substantial capacity and safety concerns. The project faced delays due to environmental challenges. Between 1997 and 2005, the segment experienced nearly 1,000 crashes, including 33 fatalities.

The project widened the existing two-lane roadway into a four-lane highway with a grass median. The improvements included better roadway alignments, replacement of bridges, and improved intersections, including the US 17/US 21 intersection, which was changed into a diamond interchange with a roundabout. The estimated cost for the entire project was $173.4 million.

Name designations
Several sections of the highway have name designations. A section in the Crosstown from Cannon Street and Spring Street to the eastern terminus of I-26 is named the Septima P. Clark Parkway, after a U.S. civil rights activist. A 3.6 mi section in West Ashley running from South Carolina Highway 7 (SC 7) to South Carolina Highway 171 (SC 171) is named the Charleston Nine Memorial Highway, in honor of nine Charleston firefighters killed in the line of duty in the Charleston Sofa Super Store fire on June 18, 2007. A section in Beaufort and Colleton counties is named the W. Brantley Harvey Highway. A section from 8th Avenue North to Starwatch Drive in Horry County is named the George Rayford Vereen Highway. A section from Old Jacksonboro Road to South Carolina Highway 7 (SC 7) is named the Curtis B. Inabinett, Sr. Highway.