Text Size:   A+ A- A   •   Text Only
Site Image

Myrtle Creek Advanced Curve Warning System
An advanced curve warning system was deployed on the Interstate 5 Myrtle Creek curves in April 2004. It uses radar coupled with a variable message sign (VMS) to warn motorists driving too fast to reduce their speeds. Dynamic curve warning systems are more effective in encouraging drivers to comply to a safer speed than a static sign board. They measure the speed of the vehicle approaching the curve and display a flashing message on the roadside VMS for the driver to slow down in preparation for the curve ahead.  For more information, please see the reference paper below.
Old signs at Myrtle Creek Curves
Current Variable Message Sign at Myrtle Creek Curves
Five of these systems were deployed on Interstate 5 in northern California near the Sacramento River Canyon. It was found that the average speed of all trucks that go through these curves was lower than the posted speed limits and was reduced by an average of four percent after installation of these systems. Click the following link for more detailed information on this project in northern California.

References and links
Bertini, R.L., Monsere, C.M., et al. Field Evalutaion of hte Myrtle Creek Advanced Curve Warning System, Department of Civil & Environmental Engineering, Portland State Univeristy, June 2006.
Sacramento Canyon Curve Warning System Evaluation Final Report by Western Transportation Institute (PDF File, 2.05 MB)