Four road transport externalities are appraised: air pollution, noise, road congestion and road crashes. Air pollution damages include health impact, visibility, damages on building facades, losses of crops and CO2 emissions. Noise only takes into accounts households decreased quality of live, thus ignoring other external effect that noise may cause. Road congestion costs are computed using simulation results from the assignment phase of an equilibrium urban transport model (ESTRAUS) developed for Santiago the Chile. The Santiago road network is represented by more than 8,000 links in ESTRAUS. Accidents externalities are computed using flow - risk elasticities and costs of accidents based on willingness to pay. Total tax adjusted cost are estimated as the total amount of money to be collected from motorists if a pigouvian tax were set at current marginal external costs. The larger proportion of external costs is due to road congestion (US$2,500 millions), followed by accidents external costs (US$ 900 millions). Health impacts from local air pollutants accounts for US$ 410 millons of external costs; noise, US$ 300 millions and damages on building facades, US$ 131 millions. This amount is compared against total taxes effectively paid by road motorists, a total of US$ 650 milions. The ratio of total tax adjusted costs against total taxes currently levied on motorists is above six. Not only, current taxes are not designed to encourage social optimal behaviour in the margin, but total collected taxes are only a small fraction of the total tax adjusted costs. As motorization is expected to grow in the following years, sooner or later, the government will have to address the issue in a more rational way if it aims to maximise social welfare. For the covering abstract see ITRD E137145.
Abstract