ITD applies key systems to assess winter road maintenance operations

Winter Maintenance Case Studies October 30, 2015
Printer-friendly version

The mission of the Idaho Transportation Department (ITD) is clear-cut: “Your Safety. Your Mobility. Your Economic Opportunity.” To verify and then evaluate and continuously improve the effectiveness of its winter road maintenance operations, ITD is implementing key systems for monitoring road weather and collecting data. 


ITD’s road weather information system (RWIS) includes 127 sites located throughout the state. These sites use optical cameras and lasers, and pavement sensors to measure the thickness of individual layers of ice, snow or water on road surfaces, while other sensors measure air temperature, wind speed and direction, and precipitation.


To collect accurate data on the materials applied to over 12,000 lane-miles of largely remote highways, ITD is installing a new spreader control system on its fleet of 450 snowplows. The electronic spreader control system provides two functions: 1) regulating the rate of salt and other deicing materials applied to road surfaces based on a snowplow truck’s speed, location and road surface temperature, and; 2) providing accurate data on the amount and type of materials applied, enhanced with GPS location data and nearly real-time reporting.


To date, ITD has installed the new SpreadSmart Rx spreader control system from Cirus Controls on 288 of its snowplow trucks. ITD anticipates having its entire fleet equipped within the next two years.


“The RWIS technology has allowed us to compare events across the state and pinpoint storm event similarities,” said Dennis Jensen, ITD mobility services−winter maintenance coordinator. “And the integration of spreader controls and GPS-based spreading data along with RWIS data gives ITD a window into our operations that didn’t exist before.”


ITD can now see exactly what treatment its snowplow trucks executed at RWIS locations and then match that specific material application data and timing to the RWIS road surface data, before and after treatment, to evaluate the effectiveness of its winter road maintenance operations.


“Bottom line,” said Jensen. “We can see how well we’re doing at preventing and removing ice from roadways.”


ITD defines its mobility index as the percentage of time a traveler’s mobility is not significantly impeded during winter storms. ITD’s goal is 55%. Of ITD’s six operating districts, District Two (D2) was the first to fully implement snowplow trucks equipped with the new spreader control system. To meet ITD’s mobility goal, D2 made significant changes to its product selection, timing and material application rates in the 2014-2015 winter season. The changes were based primarily on data supplied from the spreader control system and RWIS sites. D2 surpassed ITD’s 55 percent goal and achieved a 70% mobility index.   


“Without the Cirus and RWIS databases and matching those together for critiques, I am confident to say D2 would not have achieved a 70% mobility index,” said Jensen. “The technology has made a huge difference in operational planning and accomplishments.” 


In the future, ITD will continue to analyze the data supplied by its RWIS and electronic spreader control systems to evaluate and improve its snow and ice control operations and fulfill its mission of keeping winter travelers safe, mobile and economically available. “Thanks to empirical data, we can continue to make stronger correlations between efforts and results,” said Steve Spoor, ITD maintenance services manager.

  • Each winter, the Idaho Transportation Department is charged with snow and ice control on over 12,000 lane-miles of highway covering mountain passes to rolling hills and valley floors.
  • An Idaho Transportation Department snowplow truck equipped with the SpreadSmart Rx electronic spreader control system from Cirus Controls.
Overlay Init