ODOT implements weather-activated speed signs

Oregon Department of Transportation (ODOT) has implemented digital variable speed limit signs over a thirty-mile stretch of Interstate 84 between Baker City and La Grande, replacing the standard speed signs in that area. The new signs will use traffic, road, weather and visibility sensors to lower the legal speed limit when ice, snow, fog or a wreck ahead requires drivers to slow down. Along with identifying the current legal speed limit, the digital displays can also show the reason for a reduced speed,
November 18, 2016 Read time: 2 mins
5837 Oregon Department of Transportation (ODOT) has implemented digital variable speed limit signs over a thirty-mile stretch of Interstate 84 between Baker City and La Grande, replacing the standard speed signs in that area.

The new signs will use traffic, road, weather and visibility sensors to lower the legal speed limit when ice, snow, fog or a wreck ahead requires drivers to slow down. Along with identifying the current legal speed limit, the digital displays can also show the reason for a reduced speed, such ‘ice’ or ‘low visibility’.

Roadside sensors feed temperature, visibility, road surface grip (traction), vehicle speeds and moisture levels data into the variable speed limit sign system measure. If a majority of cars and trucks are slowing down due to weather, poor road conditions, or a wreck ahead, the sensors can send a message to the signs to reduce the speed for all drivers. Likewise, when sensors detect poor traction, low visibility or other hazardous conditions, speed limits will be lowered and an appropriate warning message can be displayed. ODOT staff will also be able to manually adjust the speed limits, such as when a crash occurs or when construction activities require a slower speed.

“This section of freeway is positioned between the Eagle Cap and Elkhorn mountain ranges,” said ODOT Area Manager Ken Patterson. “This often creates microclimates with more severe weather patterns than adjacent sections of freeway.”

Ice, high winds with blowing snow, and limited visibility are some of the challenging conditions that catch motorists off-guard, resulting in a higher number of crashes than similar freeway sections.

“The idea behind these new signs is to warn motorists ahead of hazardous road conditions and get them to slow down before they enter a potentially dangerous situation,” Patterson said.
Air Quality & Weather Systems Urban Traffic Control

For more information on companies in this article

Related Content

  • Sernis sees through the fog
    March 29, 2022
    Fog can reduce drivers’ visibility to nearly nothing. However, if the Sernis SR-SDSFog system, nominated for an Intertraffic Green Globe Award, is activated in foggy situations, it uses LEDs for guidance and also to warn of the presence of another vehicle in front.
    Read More
  • Workzone safety can be economically viable
    October 24, 2014
    David Crawford looks how workzone safety can be ‘economically viable’. Highway maintenance is one of the most dangerous construction industry occupations in Europe. Research from The Netherlands on fatal crashes indicates that the risk facing road workzone operatives is ‘significantly higher’ than that for the general construction workforce. A survey carried out by the Highways Agency, which runs the UK’s motorway and trunk road network, has suggested that 20% of road workers have suffered injuries from pa
    Read More
  • Continental developing road departure protection systems
    June 25, 2015
    International automotive supplier Continental is working on new road departure protection systems that aim to eliminate unintended road departures, which currently are not completely covered by today’s lateral guidance advanced driver assistance systems (ADAS), preventing fatal accidents from occurring on highways and rural roads. According to the US Department of Transportation Federal Highway Administration, approximately 55 per cent of traffic fatalities in the US involve a vehicle crossing the roadwa
    Read More
  • Communications redundancy increases VMS reliability
    December 17, 2014
    Hybrid communications to variable message signs increase resilience to natural disasters and enable deployment in remote areas, as Alan Allegretto explains. Variable Message Signs (VMSs) are a common sight and a well-proven means to improve public safety on our roads and highways. ITS professionals rank the VMS as second only to interoperable radios as the most important technology to improve effectiveness during emergency incidents and evacuations. Ironically, however, current systems suffer from one criti
    Read More

Highlighted Content