Client: Sund og Bælt

Enhancing traffic flow and safety on one of the World’s longest suspension bridges

A smoother driving experience over the Great Belt Bridge

Every day, numerous vehicles traverse traffic bridges worldwide, contributing to the movement of goods, commuting, and fostering economic development. These bridges act as lifelines for cities, enabling smoother traffic flow and reducing congestion on busy roadways. Even though the number of bridge related traffic accidents are decreasing, the consequences of bridge accidents can be devastating, causing injuries, loss of life, traffic disruptions, and substantial economic costs. With narrow driving lanes and heavy, high-speed traffic, connecting overseas traffic bridges like the Great Belt Bridge, generally represent an increased risk of traffic accidents. When adding infrastructural elements like payment tolls, it adds another layer of navigational complexity and increases risk of accidents for drivers in both small and large size vehicles. Sudden change in weather, road conditions, road layouts (e.g., number of lanes), or information flows can cause spontaneous or indecisive traffic behavior. To ensure a high level of safety for small and large size vehicles crossing the Danish Great Belt Bridge, Sund & Baelt (the organization responsible for operating and maintaining the bridge and payment toll) launched a behavior change program optimizing traffic flow, minimize travel time, and mitigating risk of traffic accidents.

Promoting traffic safety and efficiency

The Great Belt Bridge, an 18 km road link connecting eastern and western Denmark, serves as a critical traffic point with over 11 million cars crossing annually. To ensure seamless traffic flow, speed control, and safety on the bridge and the digital payment tolls, Sund & Baelt partnered with Krukow to maintain the already high safety standards.

Mapping driver behaviors

The focus for Sund & Baelt was to mitigate risk of “almost accidents” caused by driver’s inattention, improper distancing, speeding, or the impact of extreme winds on the 254-meter-high bridge. They realized that especially the area leading up to the digital payment tolls held the risk of resulting in potentially unsafe driving behavior as drivers would spontaneously switch lanes or suddenly reverse trying to get out of the payment toll queue. To become familiar with the challenges of the payment tolls, Sund & Baelt activated insights from daily mappings of traffic flow to identify potential danger zones and create better and safer driving experiences for all drivers crossing the bridge. Through extensive research and analysis, valuable insights were gained about factors impacting traffic flow on the Great Belt Bridge. The findings led Sund & Baelt to identify four core behavioral strategies around which modifications to the road design and environment could ensure significant improvements for motorists.
The project was based around four core strategies
Create clear visual instructions and guides
Avoid uncertainty by giving clear visual guidelines at the right moments for the motorists
Create weather specific safety instructions
Protect vehicles sensitive to strong wind by introducing visual guides leading them off the bridge during extreme weather conditions
Optimize traffic flow
Enhance driving experiences, operational efficiency, and safety through a behavior led approach
Provide feedback on traffic and ques
Manage driver expectations related to e.g., waiting time at payment tolls by giving clear feedback from afar

Ensuring safety for all vehicles

The collaborative effort yielded a series of innovative solutions that optimized general safety on the Great Belt Bridge. Furthermore, targeted interventions were developed to address critical situations effectively. By strategically influencing motorists’ behavior through the implementation of cues into the environment, Sund & Baelt was able to enhance the overall flow of drivers and optimize situations with an elevated risk of unsafe driver behavior.

"Optimizing safety and flow at a bridge like the Great Belt Bridge presents challenges due to restrictions and limited opportunities for changes in signage and road layout. The innovative, simple, and effective solutions provided by the behavioral design company exceeded our expectations. We are confident that these interventions will enhance safety and traffic flow on the bridge."

Bjarne Jørgensen, Executive Director, Asset Management, Sund & Bælt Holding A/S