Diverging Diamond Interchange at N230-A2

How do you improve traffic flow and safety at a busy junction? At the junction of the N230 (Northern Ring Road Utrecht) and the A2, traffic problems have existed for years. To improve traffic flow and safety, Iv, on behalf of the Province of Utrecht, carried out two sub-projects. The speed limit on the N230 was reduced from 100 km/h to 80 km/h, with an appropriate design. Additionally, a diverging diamond interchange (DDI) between the N230 and A2 was developed. Iv provided the preliminary design for both the DDI and the downgrade. This project is notable as it involves the first permanent DDI in the Netherlands.

The diverging diamond interchange (DDI) is a new solution in the Netherlands, which led to many discussions about safety aspects. Moreover, the DDI had to be integrated into the available space, while ensuring that safety and traffic flow requirements were met and as many existing structures and buildings as possible were preserved. The downgrade of the N230 led to discussions about its necessity and the effects on livability and noise reduction. Additionally, the focus was on creating a credible road design that aligns with a maximum speed limit of 80 km/h. Through a careful design process and close collaboration with key stakeholders, such as Rijkswaterstaat and the police, a safe and widely supported design was developed.

By reducing the speed limit on the N230 from 100 to 80 km/h, traffic safety has been improved, and the downgrade contributes to better livability in the surrounding areas. The modification of the junction to a DDI ensures smoother traffic flow and fewer traffic jams. Additionally, Iv has gained valuable experience from designing the first permanent DDI in the Netherlands, which will be useful for future projects.