Using traffic bollards has proven to reduce vehicles accessing restricted zones by 78%. This minimises traffic delays and reduces emissions by over 18%.
Most importantly proper traffic management measures can reduce pedestrian deaths within city centre zones. Providing public transport with segregated lanes improves traffic flow and reduces public transport delays.
Creating areas which are only accessible to public transport and emergency service vehicles can encourage park and ride systems which have proven to reduce emissions.
Cambridge County Council is a fantastic example of a successful bus lane management system. They have used highway approved bollard systems to pedestrianise the city. Now Cambridge is incredibly cycle-friendly and traffic emissions have been reduced dramatically.