Skip Ribbon Commands
Skip to main content


Sign up to receive press releases and media announcements by region or choose to receive all news and updates from SCDOT.


Sep 10
SCDOT and USC Release Survey Results on the I-526 Extension Project

           A solid majority of Charleston area residents who are likely to be most affected by the extension of the Mark Clark Expressway favor building this extension along the South Carolina Department of Transportation’s (SCDOT’s) proposed route, known as Alternative G.  This is the conclusion of a survey commissioned by the Department of Transportation conducted by the University of South Carolina’s Institute for Public Service and Policy Research. 

            This survey was conducted by mail, with mail and telephone follow-ups between July 25 and September 1, 2012.  Five thousand households in the area that is most likely to be affected by the proposed extension of the Mark Clark Expressway -- zip codes 29407, 29412, 29414, 29439, 29455, and 29487 -- were selected randomly and asked to participate in this study. Information was provided from 2,189 households. The overall response rate for this study was 44.5%.
            Overall, 72.2% of respondents in the target area favor building the extension of the Mark Clark Expressway along this proposed route and 27.8% are opposed. Not only does a significant majority of adults in this area support this proposed extension, but a majority of each group examined in this study does as well.
            Although there are significant differences in level of support for this proposed extension across groups, a majority of each group examined in this analysis exhibited support for this project.  Across zip codes, for example, the lowest percentages in favor of this proposed extension were found in zip codes 29487 and 29412.  Even in these two areas, however, there was majority support for this proposal: 60.0% in zip code 29487 and 62.8% in 29412.
            Similarly, a higher percentage of older than younger respondents favored the proposed extension.  Even among those under 30, there was a solid majority (68.0%) in favor of the extension, as there was among those ages 30 to 44 (69.4%).  The percentage in favor increased to 73.1% among those ages 45 to 64, and to 80.4% among those age 65 or older.
            Men were more likely than women to favor the extension of the Mark Clark Expressway along the proposed route, 78.7% to 67.4%. Although a lower percentage of women than men supported the proposed extension, approximately two-thirds of this group indicated that they favored it.

            Differences across races were statistically significant, but a majority of each group was in favor of building the extension: 81.8% of African-Americans, 70.2% of whites, and 65.3% of those of other races indicated that they favored building the extension of the Mark Clark Expressway along the proposed route.

            In theory, in 19 cases out of 20, overall results based such samples will differ by no more than 3.2 percentage points in either direction from what would have been obtained by seeking to interview all adult residents in the target area.
            A determination on the path forward for the project will be based on discussions between Charleston County, the South Carolina State Transportation Infrastructure Bank, SCDOT, and the Federal Highway Administration.
                                                      # # # # #

 ‭(Hidden)‬ Blog Tools