Congestion pricing, transit subsidies and dedicated bus lanes: Efficient and practical solutions to congestion

Abstract

We analyze urban congestion management policies through numerical analysis of a simple model that: allows users to choose between car, bus or an outside option (biking); consider congestion interactions between cars and buses; and allow for optimization of frequency, vehicle size, spacing between stops and percentage of capacity to be dedicated to bus lanes. We compare resulting service levels, social welfare and consumer surplus for a number of different policies and find that: (i) dedicated bus lanes is a better stand-alone policy than transit subsidization or congestion pricing. The latter is marginally better than subsidization but has a negative impact in consumer surplus. (ii) Efficient transit subsidies are quite large since in many cases first-best transit price is negative; establishing dedicated bus lanes or implementing congestion pricing render subsidies unnecessary for high demand levels. (iii) Both subsidization and dedicated bus lanes would count with public support while congestion pricing would probably encounter opposition. (iv) Transit subsidies and/or congestion pricing do not induce large changes on optimal bus size, frequency, circulation speeds and spacing between stops in mixed-traffic conditions: dedicated bus lanes do. (v) In all cases analyzed, revenues from congestion pricing are enough to cover transit subsidies; the optimal percentage of capacity that should be devoted for bus traffic is around one third.