Access Management Strategies
Access management techniques, such as access point (including streets and driveways) spacing, turn lanes, and auxiliary lanes, can improve congestion on roads by removing speed differentials from through-lanes. Speed differentials are the difference in speeds between a vehicle that is slowing to make a turn and the trailing vehicle that is continuing past the access point. For instance, if a turning vehicle slows to 10 mph to make a rightturn and a trailing through-vehicle is traveling at 40 mph, the speed differential is 30 mph. The trailing vehicle, and likely others behind it, must decrease its speed, or change lanes, to avoid a crash. Higher access point densities and absence of turn lanes increase the presence of speed differentials and the resulting "slow and go" traffic.