GREENVILLE, S.C. – Construction work continues on the second largest transportation infrastructure project ever undertaken by the South Carolina Department of Transportation (SCDOT).
Motorists should continue to remain alert for new traffic patterns, temporary detours and intermittent lane closures while traveling through SCDOT’s $231 million dollar Gateway Project, which aims to modernize the I-85 and I-385 Interstate Interchange in Greenville County. The SCDOT’s contractor, the Flatiron-Zachry Joint Venture, is forecasting work for the second half of 2016 to focus on the construction of the new collector/distributor lanes on I-385 (between Butler Road and I-85), the continued rehabilitation of the asphalt pavement on I-85 North between Mauldin Road and the GSP Airport exit, the re-location of Chrome Drive (to behind Harley Davidson), the replacement of the I-385 southbound to I-85 northbound ramp bridge and the replacement of the I-85 northbound to I-385 northbound ramp bridge.
Since the end of 2015 the Gateway Project has focused primarily on utility relocations, setting the stage for construction work to take place behind concrete barrier walls, improving the ride on I-85 and preparing several locations for new bridge construction. The Gateway Project identified more than 135 utility conflicts during the design phase and the respective utility companies have been working diligently to relocate their impacted infrastructure, collectively reducing the number of conflicts to 25, or a reduction of 82 percent. Some of the notable utility relocations which have been completed so far include: the Duke Power overhead transmission line crossing near the I-385 bridge over Garlington Road, the relocation of the Piedmont Natural Gas lines near the Sam’s Club, the relocation of Greenville Water’s 16” main under I-85 near Roper Mountain Road, the relocation of AT&T’s duel 600-pair fiber lines on Woodruff Road (which provides internet and phone service to much of the area), and the relocation of Metro Sewer’s 8” sanitary line along Chrome Drive.
In addition to the bridges already scheduled to be replaced as part of the Gateway Project, the I-385 bridge over Garlington Road will be replaced as well. During the design phase, the Flatiron-Zachry Joint Venture proposed replacing these bridges from the ground up as an alternative to the contractual requirement of only rehabilitating the concrete riding surface, but leaving the beams and supports in-place. SCDOT evaluated this plan and decided it was best to accept this $5.3 million proposal as it reduces future maintenance costs and will push the need for another major bridge project within the interchange off into the distant future. This change to the project adds 70 days of additional contract time to complete.
The Gateway Project has also encountered unexpected delays in securing all the required environmental permits to construct this project. First, at the I-85 crossing over Rocky Creek near Pelham Road, the Gateway Project was forced to change the original design because of a recent re-evaluation of the Flood Maps issued by the Federal Emergency Management Agency (FEMA) for this stream. The updated Flood Maps required the Gateway Project to accommodate for a higher flood elevation and therefore a more expansive flood plain area. The necessary design modifications resulted in additional retaining walls to minimize this project’s impact to the newly classified flood plain boundaries. Also, this project has added new “flood warning” signs near Rocky Creek as a temporary measure in the event Rocky Creek were to threaten to overtop the interstate. A permanent solution to resolving the potential of overtopping at this location is being evaluated by SCDOT as part of the future I-85 widening slated for construction in the early 2020s. The Gateway Project’s second environmental challenge arose from a property owner, who voiced concerns regarding a drainage outfall culvert adjacent to his property along I-85. His concerns resulted in a delay to the acquisition of this project’s environmental permit. While the full effect of these two environmental impacts is still being evaluated, they are currently forecasted to set the project back by at least five months.
Recent work on the project serves as a reminder of why this major infrastructure project is needed. The contractor was driving support-of-excavation piles recently alongside the I-85 northbound to the I-385 northbound ramp bridge when crews observed that one of the two columns on the existing bridge was experiencing abnormal spalling and cracking during the operation. The bridge was quickly closed to all traffic until SCDOT and the Flatiron-Zachry Joint Venture could perform a more detailed evaluation of the column. Within a few days, the engineers decided that encasing the column with a reinforced concrete jacket would satisfactorily stabilize the column until the bridge is taken out of service later this year. The Flatiron-Zachry Joint Venture completed the repair in just over a week’s time. In addition, the Gateway Project has decided, as an additional precautionary measure, to retrofit several other existing columns on the project using a product manufactured by Spartanburg-based Milliken Infrastructure Solutions to reduce the chances of this same issue occurring again. Milliken Infrastructure Solutions’ carbon fiber and epoxy wrapping fit well with this project’s needs and allowed the project to support an Upstate business.
The Gateway Project is currently forecasted to finish in late 2019 and is being funded by Act 98 of 2013 (which provided SCDOT with additional funding for bridge, resurfacing and mainline interstate projects), the Federal Highway Administration (FHWA) and GPATS (the Greenville-Pickens Area Transportation Study Committee).
For more information about the I-85/I-385 Gateway project, including construction updates and lane closure information, please visit the I-85/I-385 project website at www.85385gateway.com or via social media at Facebook (www.facebook.com/85385gateway) and Twitter (www.twitter.com/85385gateway)