The role of monetarization in decision methods for traffic noise abatement measures

Traffic noise, from road, railway and aircraft sources, has a serious impact on people's health. Increased health risks and annoyance lead to a lower state of wellbeing, which, at least partially, translates back to a negative impact on economy. Thankfully, many noise abatement measures exist which reduce the external impact of traffic noise. But they need to be financed and maintained, and they may spoil the scenery (noise barriers) or hinder traffic (speed limits). Decision makers want to weigh all the pros and cons before deciding to invest in a noise barrier, apply rail dampers or alter the flight routes. Many decision methods are based on some form of cost-benefit analysis. Different methods are compared in this paper. Quantification of the health benefits may be done by different monetarization techniques, including the willingness-to-pay. Some benefits or damages, however, cannot or should not be expressed in money. Other decision-making methods such as multi-criteria decision analysis may be able to improve the integral balance of all pros and cons, and may also increase public approval. Simpler methods also exist for simpler cases. The comparison and evaluation of the various decision methods identified are supported by case studies from different European countries.