Interstate 526
{{short description|Highway in South Carolina}}
{{Use American English|date=April 2025}}
{{Use mdy dates|date=March 2015}}
{{Infobox road
|state=SC
|type=I
|route=526
|map={{maplink-road|from=Interstate 526.map}}
|map_custom=yes
|map_notes=I-526 highlighted in red; future section in blue; unbuilt future section in orange
|alternate_name=Mark Clark Expressway
|length_mi=19.56
|length_ref={{cite web |year=2018 |title=Table 2: Auxiliary Routes of the Dwight D. Eisenhower National System Of Interstate and Defense Highways as of December 31, 2018 |url=https://www.fhwa.dot.gov/planning/national_highway_system/interstate_highway_system/routefinder/table02.cfm |work=Route Log and Finder List |publisher=Federal Highway Administration |accessdate=January 22, 2022}}
|counties=Charleston, Berkeley
|direction_a=West
|terminus_a={{Jct|state=SC|US|17|SC|7}} in Charleston
|junction={{Jct|state=SC|I|26}} in North Charleston
{{Jct|state=SC|US|52|US|78}} in North Charleston
|direction_b=East
|terminus_b={{Jct|state=SC|US|17|BS|526|dab2=Mount Pleasant}} in Mount Pleasant
|established=1989
|spur_type=I
|spur_of=26
|previous_type=SC
|previous_route=522
|next_type=SC
|next_route=527
}}
Interstate 526 (I-526) is a {{convert|19.56|mi|km|adj=on}} auxiliary route of I-26, providing a partial beltway around Charleston, South Carolina, in the United States. The route serves several purposes, firstly, as a bypass for through traffic on U.S. Route 17 (US 17) to avoid downtown Charleston, and, secondly, for traffic on I-26 bound for the coastal towns located north and south of Charleston. The route is not yet complete, as the western terminus it is planned for the route to be extended an additional {{Convert|10|mi|km}}. After the eastern terminus, the roadway continues as a short business route, known as Interstate 526 Business (I-526 Bus.).
Route description
I-526 begins at an incomplete interchange with US 17 (Savannah Highway) and South Carolina Highway 7 (SC 7, Sam Rittenberg Boulevard) in the West Ashley section of the city of Charleston, just north of the Stono River. The interchange includes a loop ramp from northbound US 17, a ramp from southbound US 17, and a half-diamond interchange with SC 7. The four-lane freeway heads north past the Citadel Mall and meets SC 461 at a partial cloverleaf interchange. SC 461 heads west as Glenn McConnell Parkway and east as Paul Cantrell Boulevard; both directions lead to SC 61 (Ashley River Road). I-526 crosses SC 61 and uses the General William C. Westmoreland Bridge to cross the Ashley River into the city of North Charleston. The freeway has diamond interchanges with Leeds Avenue and SC 642 (Dorchester Road) and crosses over CSX's Charleston Subdivision.
I-526 continues through a connected pair of half-diamond interchanges with Montague Avenue and International Boulevard. Both streets lead to the North Charleston Coliseum and Charles Towne Square; the latter one is the access road for Charleston International Airport. The Interstate curves east and reaches its junction with I-26, which is a cloverleaf interchange except for a flyover ramp from eastbound I-526 to westbound I-26. I-526 crosses over Norfolk Southern Railway's SC Line and has a partial cloverleaf interchange with Rivers Avenue, which carries US 52 and US 78. The Interstate continues from its overpass of the U.S. Routes as a viaduct above wetlands along Filbin Creek. The viaduct crosses over the CSX rail line again and has a four-ramp partial cloverleaf interchange with Rhett Avenue and a half-diamond interchange with Virginia Avenue. The Rhett Avenue interchange includes a U-turn ramp that allows access from westbound I-526 to Virginia Avenue and from the avenue to eastbound I-526.
I-526 crosses the Cooper River on the high-level Don N. Holt Bridge and enters the Daniel Island section of the city of Charleston in Berkeley County. The freeway has partial cloverleaf interchanges on either side of Beresford Creek with Clements Ferry Road and Seven Farms Drive/River Landing Drive. Both interchanges lead to Blackbaud Stadium, home of the Charleston Battery, and the Family Circle Tennis Center, home of the Family Circle Cup. I-526 continues southeast across the Wando River on the James B. Edwards Bridge back into Charleston County and the town of Mount Pleasant. The freeway has a partial cloverleaf interchange with Long Point Road and curves south at Hobcaw Creek. I-526 has a partial flyover interchange to and from US 17 in the direction of Georgetown before the Interstate reaches its eastern terminus at a partial cloverleaf interchange with US 17 (Johnnie Dodds Boulevard). The highway continues as I-526 Bus., a four-lane highway that follows Chuck Dawley Boulevard to SC 703 in the center of Mount Pleasant.
All of I-526 is included as part of the National Highway System, a system of roadways important to the nation's economy, defense, and mobility.{{cite web|title=National Highway System: Charleston--North Charleston, SC|url=http://www.fhwa.dot.gov/planning/national_highway_system/nhs_maps/south_carolina/charleston_sc.pdf|archive-url=https://web.archive.org/web/20151017132129/http://www.fhwa.dot.gov/planning/national_highway_system/nhs_maps/south_carolina/charleston_sc.pdf|url-status=dead|archive-date=October 17, 2015|publisher=United States Department of Transportation|date=October 1, 2012|access-date=August 14, 2013}}
History
Planning of the freeway dates back to the 1960s; construction on the first section began in 1979. Opened in 1982 as an unnumbered freeway, it traversed from Ashley River Road (SC 61) to Leeds Avenue, crossing over the Ashley River.
In 1985, the freeway became SC 31, connecting US 17/SC 7 to Dorchester Road (SC 642). By 1987, it extended to International Boulevard, providing access to the Charleston International Airport.{{cite map |publisher= South Carolina Department of Transportation |url= http://digital.tcl.sc.edu/cdm/singleitem/collection/scrm/id/787/rec/5 |format= PDF |title= General Highway Map, Charleston County, South Carolina |cartography= SCDOT |year= 1987 |access-date= May 20, 2013}}
In 1989, the freeway was rechristened as I-526 after it connected with I-26 (exit 212). In 1992, I-526 was extended east over the Cooper River to Daniel Island, then over the Wando River to Mount Pleasant and its current eastern terminus with US 17 and I-526 Bus.{{cite map |publisher= South Carolina Department of Transportation |url= http://digital.tcl.sc.edu/cdm/singleitem/collection/scrm/id/771/rec/2 |format= PDF |title= General Highway Map, Charleston County, South Carolina |cartography= SCDOT |year= 1996 |access-date= May 20, 2013}}
In 1993, the Robert B. Scarborough Bridge was opened, connecting downtown Charleston with James Island; it is signed as SC 30. Since 1993, several residents and groups in the area have fought against the completion of I-526, which will connect both James Island and Johns Island.{{cite web |url= http://coastalconservationleague.org/projects/i-526-extension/ |title=I-526 Extension |publisher= Coastal Conservation League |date=July 28, 2010 |access-date=September 19, 2011}}{{cite web|url=http://www.nix526.org |title=So Much to Lose For So Little Gain |publisher=Nix 526 |access-date=September 19, 2011}} {{citation needed span|Approximately {{convert|10|mi|km}} separate the eastern terminus of I-526's current extent from the eastern terminus of SC 30. The mileage markers and exit numbers on both SC 30 and I-526 are based on an eventual merging of the routes, with miles 1 to 3 occurring on SC 30 and miles 10 to 30 used on the current I-526 route.|date=February 2024}}
Future
The proposed missing section of I-526 was the subject of an environmental study that was completed in early 2014.{{cite web|url=http://www.dot.state.sc.us/i526/ |title=SCDOT - I-526 - Welcome to the Mark Clark Expressway! |publisher=SCDOT |date=September 30, 2010 |access-date=May 20, 2013}} Various alternative routings and options are being reviewed, but the general plan is to extend south from US 17 to Johns Island and then east to James Island, where it will connect with SC 30 (possibly renumbering it). Some alternatives shown include the possibility that it will be built in expressway grade instead, falling short of being labeled an Interstate Highway.{{cite map |format=PDF|author= Staff |url= http://www.scdot.org/MCE/pdfs/RPA_Overview.pdf |title= RPA Overview |work= Mark Clark Expressway Environmental Impact Study |publisher= South Carolina Department of Transportation |access-date= May 20, 2013}}
Citing Charleston County's inability to provide funds to cover the project's increased cost, the State Transportation Infrastructure Bank (SIB) board voted on May 26, 2016, to abandon the proposed extension of I-526 across James and Johns Islands.{{cite web|url=http://www.thestate.com/news/politics-government/politics-columns-blogs/the-buzz/article80057052.html|title=S.C. agency moves to walk away from Charleston's I-526 extension}}
In 2021, SCDOT revived the 526-extension project. As of May 2023, they are aiming to start construction by 2025.{{cite web|url=https://www.scdotmarkclark.com/the-latest |title=The Latest- Mark Clark Extension|publisher=South Carolina Department of Transportation|access-date=April 22, 2022}}{{cite news |last1=Harris |first1=Anna |title=SCDOT breaks down the costs of the I-526 extension |url=https://www.live5news.com/2023/01/27/scdot-breaks-down-costs-i-526-extension/ |access-date=20 July 2023 |work=www.live5news.com |date=27 January 2023 |language=en}} In December 2023, the South Carolina Joint Bond Review Committee approved the state's Transportation Infrastructure Bank's action Tuesday afternoon of providing $75 million for preliminary costs in the project, which is dubbed the Mark Clark Extension Project.{{cite news |last1=Johnson |first1=Emily |title=SC Committee approves $75 million toward I-526 extension, includes stipulation |url=https://www.live5news.com/2023/12/05/sc-committee-approves-75-million-toward-i-526-extension-includes-stipulation/ |access-date=10 March 2024 |work=www.live5news.com |date=5 December 2023 |language=en}}
On May 12th, 2025, the SIB voted once again to abandon the project, citing Charleston County's failure to pass a half-percent sales tax to help fund the project.{{cite news |last1=Slade |first1=David |title=The 526 Mark Clark Extension project is no more, officially killed by state officials Monday |url=https://www.postandcourier.com/news/mark-clark-extension-526-charleston-county-land/article_4197ad20-4dc7-44e6-82aa-eeebe133c16e.html |access-date=14 May 2025 |work=The Post and Courier |date=12 May 2024 |language=en}}
Exit list
{{SCint|exit
|county=Charleston
|cspan=10
|location=Charleston
|lspan=2
|mile=10.00
|exit=10
|road={{jct|state=SC|US|17|SC|7|name1=Savannah Highway|name2=Sam Rittenburg Boulevard|location1=Savannah}}
|notes=Western terminus
}}
{{SCint|exit
|mile=11.39
|exit=11
|road={{jct|state=SC|SC|461|SC|61|to2=y|name1=Paul Cantrell Boulevard / Glenn McConnell Parkway|name2=Ashley River Road}}
|notes=Split into exits 11A (south) and 11B (north)
}}
{{jctbridge|exit
|location_special=Ashley River
|bridge=General William C. Westmoreland Bridge
}}
{{SCint|exit
|location=North Charleston
|lspan=7
|mile=13.91
|exit=14
|road=Leeds Avenue
}}
{{SCint|exit
|mile=14.74
|exit=15
|road={{jct|state=SC|SC|642|name1=Dorchester Road|road|Paramount Drive}}
}}
{{SCint|exit
|mile=15.58
|exit=16
|road={{jct|extra=airport}} Montague Avenue / International Boulevard – Charleston International Airport
|notes=Split into exits 16A (Montague Avenue and International Boulevard) and 16B (Airport) eastbound
}}
{{SCint|exit
|mile=17.04
|exit=17
|road={{jct|state=SC|I|26|city1=Charleston|city2=Columbia}}
|notes=Split into exits 17A (east) and 17B (west) westbound
}}
{{SCint|exit
|mile=17.65
|exit=18
|road={{jct|state=SC|US|52|US|78|name2=Rivers Avenue}}
|notes=Split into exits 18A (east) and 18B (west)
}}
{{SCint|exit
|mile=19.09
|exit=19
|road=North Rhett Avenue
|notes=Includes direct U-turn ramp from westbound I-526 exit to eastbound I-526 entrance
}}
{{SCint|exit
|type=incomplete
|mile=19.39
|exit=20
|road=Virginia Avenue
|notes=Eastbound exit and westbound entrance; movements between Virginia Avenue and I-526 to and from Mount Pleasant are made using the exit 19 U-turn ramp
}}
{{jctbridge|exit
|river=Cooper River
|bridge=Don N. Holt Bridge
}}
{{SCint|exit
|county=Berkeley
|cspan=2
|location=Charleston
|lspan=2
|mile=22.50
|exit=23
|road=Clements Ferry Road
|notes=Split into exits 23A (south) and 23B (north) eastbound
}}
{{SCint|exit
|mile=23.96
|exit=24
|road=River Landing Drive / Seven Farms Drive / Island Park Drive – Daniel Island
}}
{{jctbridge|exit
|river=Wando River
|bridge=James B. Edwards Bridge
}}
{{SCint|exit
|county=Charleston
|cspan=3
|location=Mount Pleasant
|lspan=3
|mile=27.46
|exit=28
|road=Long Point Road
}}
{{SCint|exit
|type=incomplete
|mile=28.69
|exit=29
|road={{jct|state=SC|US|17|dir1=north|city1=Georgetown}}
|notes=Eastbound exit and westbound entrance
}}
{{SCint|exit
|mile=29.56
|type=incomplete
|exit=30
|road={{jct|state=SC|US|17|name1=Johnnie Dodds Boulevard|BS|526|dab2=Mount Pleasant|dir2=east|name2=Chuck Dawley Boulevard|to3=y|SC|703|city1=Charleston}}
|notes=Eastern terminus; roadway continues as I-526 Bus.; no access from eastbound I-526 to northbound US 17 or from southbound US 17 to westbound I-526
}}
{{Jctbtm|exit|keys=incomplete}}
Interstate 526 Business
{{Infobox road small
|state=SC
|type=BS
|route=526
|location=Mount Pleasant, South Carolina
|formed=1992
|length_mi=1.570
}}
Interstate 526 Business (I-526 Bus.), per the South Carolina Department of Transportation South Carolina Highway 526 Spur,{{cite map|title=Charleston Urban Area|url=https://info2.scdot.org//GISMapping/GISMapdl/Charleston_Metro_2018.pdf|sheet=24|publisher=South Carolina Department of Transportation|date=August 2020}} is a {{convert|1.57|mi|km|adj=on}} four-lane boulevard-grade business spur of I-526 along Chuck Dawley Boulevard between Johnnie Dodds Boulevard (US 17) and Ben Sawyer Boulevard (SC 703).{{google maps |url=https://maps.google.com/maps?saddr=I-526BUS%2FInterstate+526+E&daddr=Chuck+Dawley+Blvd&hl=en&ll=32.805276,-79.849749&spn=0.030191,0.055747&sll=32.796185,-79.85919&sspn=0.015097,0.027874&geocode=FUuz9AEdLJc9-w%3BFd5n9AEdImc9-w&mra=dme&mrsp=1&sz=16&t=p&z=15 |title=Overview map of I-526 Bus. (Mount Pleasant) |link=no |access-date=May 19, 2013 }}
I-526 Bus. is not part of the National Highway System.
{{Jcttop|state=SC|location=Mount Pleasant|county=Charleston|length_ref=}}
{{SCint
|mile=0.000
|road={{Jct|state=SC|I|526|dir1=west|US|17|name2=Johnnie Dodds Boulevard|city1=North Charleston|city2=Charleston|city3=Georgetown|nolink1=y}}
|notes=Western terminus; continuation as I-526; former US 701
}}
{{SCint
|mile=1.570
|road={{Jct|state=SC|SC|703|name1=Ben Sawyer Boulevard|city1=Charleston|city2=Sullivan's Island}}
|notes=Eastern terminus
}}
{{Jctbtm}}
{{Clear}}
See also
- {{Portal-inline|United States}}
- {{Portal-inline|U.S. roads}}
{{Clear}}
References
{{reflist|refs=
{{cite map|publisher=South Carolina Department of Transportation|title=Highways - Zipped Shapefile of roads maintained by SCDOT - Statewide|url=http://dbw.scdot.org/GISMapping/pdfs/GIS/Statewide_Highways_2012.zip|format=ESRI shapefile|year=2012|access-date=May 31, 2012}}{{Dead link|date=January 2020 |bot=InternetArchiveBot |fix-attempted=yes }}
}}
External links
{{Attached KML|display=title,inline}}
- {{commons category-inline}}
- [https://www.angelfire.com/sc3/scroads/i526.html Mapmikey's South Carolina Highways Page: I-526]
{{3di|26}}
Category:Transportation in Charleston County, South Carolina