SENSITIVITY OF TRAVEL DEMAND TO TOLL CHARGES, EXPERIENCE AT WEST GATE

Australia has relatively few road or bridge facilities on which tolls are levied. For most of those which do exist, the relationships between the level of tolls and the level of travel demand have not been studied in detail. Since its opening in 1978, the travel demand patterns of the West Gate bridge in Melbourne have been monitored closely to determine patterns of usage by various vehicle types by time of day, day of week and season of year. A significant increase in toll levels (up about 30 per cent) occured in August 1982. The bridge's permanent reporting systems allowed the traffic effects to be traced, thus giving a reasonably good indication of the sensitivity of travel demand to toll levels. An elasticity value of -0.3 was indicated by the traffic response to the toll increase; this is consistant with previous monitoring studies at West Gate and with highway toll experience in the United States. This conclusion is of considerable importance to future demand (and revenue) management of the West Gate bridge and possibly of toll facilities elsewhere. (Author/TRRL)