Wrong-way driving crashes make up only one percent of all accidents in the U.S. annually, according to the U.S. Department of Transportation's Federal Highway Administration.

The numbers may be low, but the result is often deadly.

Two people died Tuesday after a head-on collision due to a wrong-way driver on eastbound I-80 in Natomas. The tragic accident is just one of a string of deadly wrong-way wrecks in Sacramento over the past several years. From January to May in 2015, there were five wrong-way crashes in the Sacramento area that left 16 people dead, according to the California Department of Transportation (Caltrans).

Because of the wrong-way crashes in 2015, Caltrans and the California Highway Patrol (CHP) recently rolled out a pilot program along I-5, US 50, and I-80 in Sacramento and Yolo County using new methods to combat wrong-way driving.

The pilot program includes two-way, red-and-clear reflective pavement markers that turn red if you're going the wrong way. The program also installed revised "wrong way" signs with blinking lights and added active monitoring systems. The monitoring systems use dual radars to detect wrong-way drivers and activate red flashing lights bordering the wrong-way signs. Caltrans and the CHP are notified in real-time of the wrong-way drivers through photos and alerts.

The Sacramento pilot program is in motion, but what additional countermeasures are other states and countries using to reduce the number of wrong-way accidents?

West Nippon Expressway Company (NEXCO), a Japanese traffic and road operator, tested autonomous detection, or GPS, as a countermeasure for wrong-way driving, according to a 2010 International Road Federation (IRF) presentation. The GPS device was tested to alert wrong-way drivers through visual and audio messages. GPS detected more than 90 percent of wrong-way drivers, as long as the roads were not complex for example, straight roads or smooth curved roads.

NEXCO also found roadside CCTV can detect wrong-way drivers by analyzing footage. When traffic control detects a wrong-way driver on a video image, a warning message is sent out to message signboards and traffic control takes immediate action.

Vehicle-to-roadside communication systems were also suggested by NEXCO, where a wrong-way driver is detected and a message is sent to the driver over a roadside loudspeaker or through the radio.

Florida is testing the use of LED raised pavements as markers, according to a Caltrans report. The Florida Department of Transportation (FDOT) believes it's one of the best countermeasures for wrong-way driving.

Tire spikes may seem like a solution to immobilize wrong-way drivers but FDOT said spikes don't work for multiple reasons. First, if an ambulance needs to go up a ramp the wrong way to assist a victim, they won't be able to do so. Also, spikes are designed for low speed areas such as parking lots and parking garages so the spikes won't deflate fast enough to stop vehicles traveling at a fast speed. In addition, spikes can wear over time and break off and damage vehicles going the right way, according to FDOT.