I-670/I-270 Interchange with Hard Shoulder Running
Location: Columbus, Ohio
An innovative Active Traffic Management strategy called Hard Shoulder Running (HSR) is helping combat traffic congestion on the I-670 corridor in Columbus, Ohio. The first of its kind in the state, the Ohio Department of Transportation (ODOT) HSR pilot project – the SmartLane – is improving traffic flow in the area during peak hours. B&N led the design and implementation of the HSR, along with significant modifications to the existing I-670 and I-270 interchange.
Hard Shoulder Running
HSR temporarily uses the shoulder to provide an additional travel lane during peak congestion hours. The approach is less expensive than other options, such as traditional road widening, because it uses much more of the existing roadway infrastructure. ODOT’s HSR project is only the 14th in the country.
ODOT’s SmartLane spans seven miles of eastbound I-670 connecting downtown Columbus to the I-270 outerbelt. The left shoulder on this section of I-670 is converted into a travel lane during the afternoon peak traffic periods, including weekday evening commutes. It will remain open during heavy congestion periods and close when traffic is flowing freely, reverting the shoulder back to its normal function.
Intelligent Transportation System (ITS) technology, including 11 Dynamic Message Signs (DMS) and 46 Closed-Circuit Televisions (CCTVs), are used to communicate with the Traffic Management Center (TMC). Trained TMC personnel use this information to determine when traffic is slowing down enough to open the SmartLane. They use DMS messages to inform motorists of changes in lane usage, variable speed limits, and any emergent information such as an accident or stopped vehicle. This helps harmonize the speeds across all lanes to improve the traffic flow and safety.
Before the capacity improvements from the SmartLane could be fully realized, modifications were necessary to fix the bottleneck on I-270 at the I-670 interchange. The weave segment along I-270 north, immediately north of the interchange, operated poorly and caused traffic to back up into the I-670 corridor. To resolve this, problematic weaving movements were eliminated by braiding critical ramps in the interchange to help improve traffic flow and resolve safety issues.
The modifications also included widening the interchange to accommodate a new lane that begins where the SmartLane ends, allowing traffic to flow freely through the interchange and not force drivers from the SmartLane to merge into the general-purpose lane in a section that is still heavily congested.
Accelerating Congestion Relief
As the lead design firm, B&N completed a 1,600-sheet plan set for nine miles of roadway widening, a system interchange modification, and design of nine massive overhead gantries and DMS signs in less than nine months.
The completed SmartLane is now fully operational and helping combat traffic congestion on I-670.