December 19
I-385 Safety Improves Since Clear Zone Increased

Fewer motorists are crashing into trees and dying along a stretch of I-385 in Laurens County since several trees were removed during a widening project in 2010, according to the data from the South Carolina Department of Transportation (SCDOT).

As a part of the project, the clear zone was increased to meet the current national guidance. A clear zone is the unobstructed area beyond the edge of the traveled way that allows a driver to stop safely or regain control of a vehicle that leaves the traveled way. Clear zone values are based on many factors including: vehicle speeds, vehicle volume, and crash data. As a result, trees up to approximately 50 feet from the edge of pavement were removed.

In a 5-year span before the I-385 improvement project, there was an average of 12.4 crashes involving trees per year. In nearly 3 years since the project's completion, that number has reduced to 3.1 crashes involving trees per year. This is a decrease of 75 percent (three-fourths).

In addition, there were 6 fatalities during the 5-year period before the improvement project, or an average of 1.2 per year, on this section of I-385 - and all of which involved trees. There were no fatalities in a nearly 3-year period of study after the project's completion.

Injuries from tree crashes have decreased 65 percent, from an average of 4 per year to 1.4 per year.

Overall, including all types of crashes, there have been 22 percent fewer crashes per year since the I-385 improvement project.

"The data clearly show a significant increase in safety, which is our main goal at SCDOT," said Tony Sheppard, Director of Traffic Engineering. "From six deaths in tree-related crashes to zero during the study period is a dramatic improvement."

"The analysis of the crash data demonstrates the positive impacts of providing a forgiving roadway design and adequate clear zone for motorists of errant vehicles to safely bring their vehicle under control," Sheppard said.

The major work of the I-385 project consisted of pavement removal and reconstruction of 15 miles of I-385 from the interchange at I-26 to the just south of (Exit 16) SC 101 interchange. Additional safety enhancements included a new 10 foot outside paved shoulder a 4-foot paved inside shoulder and 57,350 feet of new guard rail was also added throughout the project.