The cost to implement a red-light extension (RLE) system on two major approaches to a single four-way signalized intersection was estimated at $16,500.

Experience assessing the accuracy and performance red-light extension (RLE) systems in Oregon.

Made Public Date


US30 and Cornelius Pass Road
United States

Summary Information

This research evaluated the implementation of a red-light extension (RLE) system to reduce red-light running (RLR) and improve safety at the intersection of US30 and Cornelius Pass Road in Portland, Oregon. The intersection operates with a 2070 controller and NWS Voyage™ firmware, and uses the NWS Voyage™ RLE function on through movements. RLE events are triggered by loop detectors located downstream from the stop line.

The table below excerpted from the source report provides an example calculation of the costs associated with the design and installation of a red clearance extension system.


Component Approximate Unit Price
2070 Signal controller with NWS Voyage™ firmware $4,500
Inductive loops $1,000 per approach*
RADAR $6,500 per approach*
Engineering time to configure settings and validate operations $1,500

* Assumes conduit in place, otherwise cost per approach could be an additional $5k to $20k.

Smart Red Clearance Extensions to Reduce Red-Light Running Crashes

Smart Red Clearance Extensions to Reduce Red-Light Running Crashes
Publication Sort Date
Hurwitz, David,
Oregon DOT and the USDOT FHWA
Other Reference Number
Repoty No. FHWA-OR-RD-16-10

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System Cost

RLE system upgrade: Approximately $8,250 per approach