Cost-benefit analysis of low-noise pavements: dust into the calculations

This paper presents a cost-benefit analysis (CBA) of roads noise measures in Norway. Low-noise pavement alternatives were compared to stone mastic asphalt with a maximum aggregate size of 11mm. The low-noise alternatives were expected to reduce the noise levels by 1-4.5dB over their lifetime, compared to the reference, but had shorter lifetime and, mostly, higher investment cost. A new element included into our CBA of low-noise asphalts is their property in terms of asphalt-wearing and dust production. Given a relationship between asphalt-wearing and airborne particulate matter, there is a potential health impact of pavement choice. Official valuations of both noise changes and PM10 changes were applied for the benefit estimations. Thin-layer asphalts obtained higher benefit-cost ratios than porous asphalts, mainly due to small changes in unit costs and technical lifetime compared to the reference. Alterations in dust production had considerable weight in the benefits, but did not considerably alter the ranking of asphalts compared to analyses not taking dust into account.