Changes in Legal and Illegal Weaving Activity After Restriping of I-85 High-Occupancy-Vehicle Lanes in Atlanta, Georgia

In September 2011, a large section of the high-occupancy vehicle (HOV) carpool lane on Atlanta’s I-85 is scheduled to be converted into a high-occupancy toll lane. The facility will remain non-barrier-separated, with double-white and double dashed lines indicating where vehicles may merge into and out of the HOT lane. The number and location of weaving locations will change when the HOT lanes are implemented, which will likely impact the effective capacity of the lanes in the corridor. In addition, automated enforcement techniques will be implemented to identify vehicles that weave into and out of the lanes at restricted locations. To help assess whether then new facility is more efficient, the research team at Georgia Institute of Technology (GT) is monitoring changes in weaving activity and vehicle throughput before and after the HOT conversion. Video data are being collected along the I-85 corridor between I-285 and SR-316 and researchers are quantifying changes weaving activity. Although the lanes have not yet opened, the Georgia Department of Transportation did contract for re-striping of the existing HOV facility, eliminating one weave section. Data sets extracted from video recordings collected to date have been generated, and some preliminary analysis of the data attempts to describe changes in weaving patterns observed to date.