Which traffic management method is implemented to enhance vehicle access control?

Gates and bollards are effective traffic management methods for enhancing vehicle access control because they physically restrict or regulate the entry and exit of vehicles within a designated area. Gates can be automated or manual, allowing control over who can enter a space, while bollards serve as physical barriers that can prevent unauthorized access and protect pedestrian areas. This combination not only ensures security but also manages the flow of traffic effectively, creating a safer environment for both vehicles and pedestrians.

The other options, while they may contribute to overall safety and traffic management, do not specifically focus on access control in the same way. Overhead walkways and vehicle routes are designed to separate types of traffic but do not necessarily control access. Temporary barriers provide flexibility for managing traffic in changing conditions, but they lack the permanence and function of gates and bollards. High impact barriers offer protection against vehicle collisions but do not actively manage access to an area.