The South Carolina Department of Transportation (SCDOT) has completed its final review of the report on the painting containment system that fell from the supports of the Don Holt Bridge on I-526 in Charleston County on July 19, 2017.
The report concludes an accumulation of rainwater resulting from an extreme and unexpected thunderstorm was the most probable cause of the failure of the system.
The report was conducted by a licensed professional engineer representing Applied Building Sciences (ABS), a leading forensic firm with experience investigating complex collapse claims. ABS was retained by the insurance company for Eagle Industrial Painting (EIP), the contractor on the painting project. The information in this report includes the material released by SCDOT in its preliminary report on August 1, 2017.
ABS’s findings indicate the weight of the rainwater on the horizontal tarp most likely caused the 1” diameter wire rope chokers to fail. The chokers were used to support the suspended platform beneath the bridge’s superstructure.
The ABS report includes statements from certified meteorologist, Lee Branscome, Ph.D. that maximum wind speeds at the top of the bridge likely reached 58 mph on the day of the incident. In addition, 1.68 inches of rainfall was recorded within five miles of the bridge between 5:00 and 6:00 p.m., the same timeframe as the failure of the containment system. The report concludes that the primary load that resulted in the failure was most likely caused by rain accumulation on the tarp and not the wind loads.
The report further observes that EIP did not have access to the containment system during the day to monitor water accumulation, because SCDOT authorized lane closures only at night. While SCDOT had not authorized a continuous, permanent daytime lane closure during the painting operation, SCDOT would have authorized emergency lane closures for tarp repairs or de-watering had it been requested. SCDOT did not receive an emergency lane closure request from EIP on July 19, 2017, which is understandable due to the suddenness and unexpected nature of the storm.
Among the motorists whose vehicles were damaged by the fallen containment system, EIP’s insurance company reports 12 vehicle owners filed claims. Ten have received payment.
SCDOT and EIP continue to evaluate processes that will eliminate or greatly reduce the likelihood of a containment failure. SCDOT once again apologizes for inconveniences caused by the incident and thanks the public for its patience as SCDOT and EIP determine how to best complete this project.
SCDOT’s Final Report on the Don Holt Bridge Containment System can be found at this link: http://www.scdot-transfer.org/SCDOTphotos/DonHoltPaintingProjectFinalReviewFindings09282017.pdf