The Georgia Department of Transportation is planning to install a modern single-lane roundabout at the intersection of State Route 81 and Snapping Shoals Road in the Ola community. The intersection has seen several configurations during the last few years in an attempt to address high crash volumes and safety concerns at the location.
In May 2019, Georgia DOT approved the project’s concept report documenting the need, purpose, cost estimate, and conceptual layout for the improvements. Project costs are estimated to total $3,108,554.75 and construction is scheduled to let in June 2021.
Project History and Justification
The intersection of SR 81 at Jackson Rd / Snapping Shoals Road operated as a two-way stop control intersection prior to 2015. The location was identified for improvements due to high crash rate and has undergone two modifications over the past 4 years. A total of 44 crashes were reported between January 2010 and December 2014. Of the recorded crashes, 26 resulted in injuries and 1 resulted in a fatality. Crash types consisted of 32 angle collisions, 1 was head-on, 7 were single-vehicle, and 4 were rear-ends. The injury and fatal crashes were predominantly angle crashes.
In an effort to analyze these crash issues, the district completed a Traffic Engineering (TE) Study on April 8, 2015. The TE Study showed that warrants for multi-way stop were met and the intersection was converted to an All-way Stop shortly after the study. After the installation of the All-Way Stop in 2015, 11 crashes were reported resulting in 3 injuries and 8 [property damage only crashes]. The predominate crash types were angle and rear end with 4 angles and 3 rear end crashes.
The TE Study also recommended the installation of a conventional single lane roundabout to address the long-term safety concerns. With the continued crash history after implementation of All-Way Stop, the district installed a mini roundabout in 2016 as a transitional project under the Quick Response program to address safety issues until a permanent solution can be implemented. Since the conversion to the mini-roundabout in 2016, the crash rate from the all-way stop has reduced, but the crash pattern has remained the same. There were 27 crashes recorded from 2016 to 2018. Of these 27 crashes, 14 were angles, 1 head on, 4 rear end, 2 sideswipes, and 6 off the road crashes.
The installation of a properly designed single lane roundabout will address historical crash patterns at the intersection, including the high percentage of angle crashes. These improvements are aligned with GDOT’s goal of Vision Zero of preventing fatalities.
Project Concept Report Page 3, Georgia DOT
The conventional single-lane roundabout will provide better speed control and design with the installation of splitter islands, horizontal alignment modifications, approach offset, and curb/gutter. The project will also include lighting, a raised center island, and mountable truck apron. The improvements will be funded through the FHWA Highway Safety Improvement Program and is a safety-focused program.
Construction is estimated to last less than one year. A traffic signal was eliminated as a possible design because the intersection does not meet the signal warrants. The installation of unwarranted traffic signals creates additional safety risks and can have negative operational impacts.
The 186 page concept report is available to view on the Georgia DOT website. Scroll down on the project page and click on “0013697_CR_MAY2019.pdf” under Project Documents.