By Bert Murillo and Ryan Dowling, Contributing Authors
Imagine a scenario where the final whistle blows at Bryant-Denny Stadium in Tuscaloosa, Ala., and 100,000 fans pour into the November evening. The Crimson Tide clinched another win, but a more formidable opponent looms: A winter storm approaches from the northwest. Caught off guard by the sudden change in weather, fans driving home struggle to navigate the hazardous conditions, and traffic becomes a standstill.
The Alabama Department of Transportation (ALDOT) faces a unique set of winter road maintenance challenges. While the state may not be synonymous with harsh winter storms, its diverse topography and unpredictable weather patterns create a complex environment for road management.
ALDOT’s West Central Region, responsible for 13 counties including Tuscaloosa, has recently implemented an innovative approach to tackle these challenges. This hybrid method combines multiple data sources, advanced modeling techniques and real-time insights to optimize winter road maintenance operations and enhance public safety.
Road Network Complexities
Unpredictability in weather conditions, especially in hard-to-forecast locations, has historically been a significant hurdle in maintaining road safety and efficiency across the Yellowhammer State.
This variability not only affects traffic but also has severe implications during extreme weather events or large-scale public gatherings without real-time road weather information.
In line with its mission to “provide a safe, efficient and environmentally sound transportation system for all customers,” ALDOT sought a solution that could fill gaps between existing fixed road weather information systems (RWISs) and deliver more accurate, localized weather information.
The goal was twofold: enhance public safety through improved road condition information and optimize maintenance operations by enabling more proactive and targeted interventions.
ALDOT’s existing traffic management centers were already responsible for notifying the public about roadway incidents that could impede normal traffic flow via its Algo Traffic app and website. However, the accuracy and timeliness of these notifications, especially regarding winter weather and changing road conditions, offered an opportunity for improvement.
Integrating Technologies
ALDOT turned to a combination of advanced weather sensors and a comprehensive visualization platform to augment existing RWIS data, improve its understanding of changing weather patterns and provide hyperlocal information to the public.
This approach integrates three key components:
Wx Horizon: A weather portal that delivers insights into weather hazard impacts on current and future road conditions. This platform, part of Vaisala’s Xweather family of products, serves as the central hub for data integration and visualization.
GroundCast Sensors: These IoT-connected devices install in the ground to measure real surface temperature, road temperatures at different depths, the amount of treatment material on the road surface and whether the pavement is wet or dry.
TempCast Sensors: Designed for easy installation on existing infrastructure, these standalone sensors measure air temperature, humidity and surface temperature without the need for pavement contact. These IoT sensors are ideal for bridges, remote locations, cold spots and other difficult locations.
Wx Horizon combines data from the GroundCast and TempCast sensors with radar information and sophisticated forecasting models. It paints a comprehensive picture of the ALDOT road network’s current state and likely future conditions.
Plus, these additional measurements further improve the accuracy of the road weather forecast. Fusing ground truth data that fills the gap between RWISs with accurate, near-term forecasting information helps road agencies improve traffic flow during adverse weather conditions. This bolsters public safety and predicts extreme temperatures to aid in proactive pavement maintenance.
By integrating this hybrid solution into its traffic management center, ALDOT will enhance the accuracy of weather-related notifications and further improve overall efficiency. This holistic view allows maintenance teams to:
- Monitor road conditions in real time across the entire network.
- Identify potential problem areas before they develop into dangerous hazards.
- Make data-driven decisions about resource allocation and maintenance interventions.
- Provide more accurate and timely information to the public.
Winter Road Maintenance
This new system has the potential to enhance public safety. By integrating the Wx Horizon platform with its existing Algo Traffic app and website, ALDOT can provide the public with real-time information about road conditions and prepare them for inclement conditions.
These details are particularly crucial during extreme weather events or high-traffic situations, such as the mass exodus following a major college football game. With more precise information about what’s happening — or might happen — on the road, travelers can make better-informed decisions about their routes and travel times, potentially reducing the risk of accidents and improving overall traffic flow.
From an operational standpoint, the new system enables ALDOT to be more proactive and efficient in its maintenance efforts. The ability to predict extreme temperatures and identify potential problem areas allows maintenance teams to pretreat roads before ice forms, allocate deicing resources more efficiently, schedule maintenance activities during optimal weather windows and avoid unnecessary treatments.
Measuring the amount of treatment material on the road surface is particularly valuable. This allows maintenance teams to apply the right amount of deicing agents, reducing waste and minimizing harsh environmental impacts.
One key advantage of this hybrid approach is its cost-effectiveness. Compact IoT sensors can be widely deployed across the road network without the need for extensive infrastructure changes, cables or external powering.
“We can be a lot more efficient and accurate in maintaining the road network,” said Ken Colvert, West Central Region TMC manager at ALDOT. “And the solution’s cost-effective, which is important.”
This cost-effectiveness is crucial for state departments of transportation and other similar agencies that often operate under tight budget constraints.
The versatility of a hybrid road network proves particularly valuable in addressing some of Alabama’s unique road maintenance challenges, like elevation changes, icy bridge surfaces and high-traffic events.
ALDOT’s implementation of this system is still in its early stages, but the department is already planning for future expansions and integrations. Understanding how weather patterns affect different parts of the road network over time would help ALDOT make more informed decisions about infrastructure investments and maintenance schedules.
Implementing this integrated sensor network and visualization represents the next step in winter road maintenance across Alabama.
Through real-time, hyperlocal weather data provision and accurate road weather forecasts, ALDOT’s new solution boosts traveler safety, improves traffic flow during adverse weather and enables more efficient and environmentally friendly road maintenance practices.
As climate change continues to bring more variable and extreme weather patterns, systems like this will become increasingly vital for transportation departments across the country. ALDOT’s experience demonstrates that the right tools and tactics turn the challenge of unpredictable weather into an opportunity for innovation and improvement in road management.
The road ahead for ALDOT and its new system looks promising. As the organization continues to refine and expand its use of this technology, the benefits for both the department and the traveling public are likely to grow.
For other DOTs watching the progress in the Heart of Dixie, this case provides a compelling example of how to leverage modern technology to create safer, more efficient road networks in the face of increasingly complex weather challenges. RB
Bert Murillo is the head of sales for Vaisala’s North American Roads division. Ryan Dowling Ryan Dowling is a sales manager at Vaisala.
