Knut Veisten

Valuation of Green Walls and Green Roofs as Soundscape Measures: Including Monetised Amenity Values Together with Noise-attenuation Values in a Cost-benefit Analysis of a Green Wall Affecting Courtyards

Economic unit values of soundscape/acoustic effects have been based on changes in the number of annoyed persons or on decibel changes. The normal procedure has been the application of these unit values to noise-attenuation measures affecting the noisier façade of a dwelling. Novel modular vegetation-based soundscape measures, so-called green walls, might be relevant for both noisy and quieter areas. Moreover, their benefits will comprise noise attenuation as well as non-acoustic amenity effects. One challenge is to integrate the results of some decades of non-acoustic research on the amenity value of urban greenery into design of the urban sound environment, and incorporate these non-acoustic properties in the overall economic assessment of noise control and overall sound environment improvement measures. Monetised unit values for green walls have been included in two alternative cases, or demonstration projects, of covering the entrances to blocks of flats with a green wall. Since these measures improve the noise environment on the quiet side of the dwellings and courtyards, not the most exposed façade, adjustment factors to the nominal quiet side decibel reductions to arrive at an estimate of the equivalent overall acoustic improvement have been applied. A cost-benefit analysis of the green wall case indicates that this measure is economically promising, when valuing the noise attenuation in the quieter area and adding the amenity/aesthetic value of the green wall.

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 11 mm. The low-noise alternatives were expected to reduce the noise levels by 1–4.5 dB 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.

Assessing conceptions of cost-benefit analysis among road safety decision-makers: misunderstandings or disputes?

Statements about economic cost-benefit analysis were assessed in a sample of European road safety decision-makers. These statements related to both principles of cost-benefit analysis and implications for applying the method to road safety projects. A procedure of information reference testing was applied, under the assumption of identifying knowledge and possible misconceptions about the method. Homogeneity and ordinal logit analyses indicated that a high sum-score correlated with economist background, while a low sum-score correlated significantly with negative attitudes towards assessing road safety policy by cost-benefit analysis. However, the sum-score from the statements cannot be regarded as an unequivocal measure of knowledge, and the responses may indicate a boundary dispute about economics as scientific knowledge versus economics as a policy tool.

Is law enforcement of drug-impaired driving cost-efficient? An explorative study of a methodology for cost–benefit analysis

BACKGROUND Road users driving under the influence of psychoactive substances may be at much higher relative risk (RR) in road traffic than the average driver. Legislation banning blood alcohol concentrations above certain threshold levels combined with roadside breath-testing of alcohol have been in lieu for decades in many countries, but new legislation and testing of drivers for drug use have recently been implemented in some countries. METHODS In this article we present a methodology for cost-benefit analysis (CBA) of increased law enforcement of roadside drug screening. This is an analysis of the profitability for society, where costs of control are weighed against the reduction in injuries expected from fewer drugged drivers on the roads. We specify assumptions regarding costs and the effect of the specificity of the drug screening device, and quantify a deterrence effect related to sensitivity of the device yielding the benefit estimates. RESULTS Three European countries with different current enforcement levels were studied, yielding benefit-cost ratios in the approximate range of 0.5-5 for a tripling of current levels of enforcement, with costs of about 4000 EUR per convicted and in the range of 1.5 and 13 million EUR per prevented fatality. CONCLUSIONS The applied methodology for CBA has involved a simplistic behavioural response to enforcement increase and control efficiency. Although this methodology should be developed further, it is clearly indicated that the cost-efficiency of increased law enforcement of drug driving offences is dependent on the baseline situation of drug-use in traffic and on the current level of enforcement, as well as the RR and prevalence of drugs in road traffic.

Selecting Road-Noise Abatement Measures: Economic Analysis of Different Policy Objectives

To satisfy new legislation, the Norwegian Public Roads Administration implemented a national facade insulation program encompassing 2,500 dwellings exposed to high levels of road traffic noise. Thereby, the road owner brought the equivalent noise levels from road traffic in compliance with a new indoor limit of 42dB. Cost-effectiveness analyses show that facade insulation was the least expensive noise-control alternative per dwelling. However, cost-benefit analyses show that the benefits were less than 20 per cent of costs. One reason for the poor benefit-cost ratio is that only the residents of the targeted dwellings benefit from at-receiver measures. Measures at the source and/or targeting the propagation paths also provide noise benefits for residents living along the same streets as the most noise exposed and inadequately insulated dwellings. A mixed noise abatement policy employing low-noise asphalts in addition to facade insulation is therefore considered. For 750 dwellings where two or more of the dwellings were located along the same road stretch, low noise asphalts replaced facade insulation as noise abatement method. Facade insulation was kept as noise abatement method for the remaining 1,750 dwellings. The mixed noise abatement policy costs more, but now provides total benefits that match the total costs. Even higher benefit-cost ratios are obtained when reframing the economic analyses within the context of a national policy to reduce noise annoyance, and when focussing solely on more densely populated areas where low- noise asphalts is a viable alternative to facade insulation. Since environmental authorities are in the process of further lowering the indoor noise limit, the road authorities should consider preparing an organisational and financial framework for implementing low-noise surfaces based on cost-benefit calculations. Such a policy would have the added benefit of improving urban soundscapes for a significant number of residents, workers, cyclists, pedestrians and children.

Valuation of Cycling Facilities with and without Controlling for Casualty Risk

Barrier effects can impact cyclists’ travel time, level of comfort, and risk of accidents. When eliciting the valuation of these elements, simultaneous estimation is called for because the perceived level of comfort may depend on the accident risk. In this paper we present the results of a choice experiment in which cyclists traded off cycling time, separated tracks, intersections, and, in one additional choice experiment, casualty risk. We find that the utility of the two barrier-reducing attributes is almost halved when controlling for accident risk. We also translate the utility to a monetary scale, making the results applicable for cost-benefit analysis.

Value for Money. Cost–Benefit Analysis

This chapter provides the results of a limited cost–benefit analysis (CBA) on selected implementation scenarios. A main challenge for CBA of ITS-based safety measures is the limited quantifiable estimates of their effects on road fatalities and injuries. As a proxy to estimating such effects, an error-based approach is applied. That is, particular ITS-based measures are assumed to help drivers avoid errors that are known to be related to particular types of accidents; the target accidents of the technologies. Such an approach to measuring benefits inevitably requires strong assumptions for quantifying the fatality/injury effects. In addition, there is also lack of empirical knowledge on the indirect effects of ITS-based safety measures; the possible impact on time use and emissions. Since such possible indirect impacts are not included in this CBA, the analysis can be considered as only partial. Even if the quantified safety effects are on the optimistic side, the resulting benefit–cost ratios are still fairly low, because of the technology costs. However, future costs are assumed to decrease, and some of the technologies might be standard equipment in more and more car models.

Structuring the Way

This chapter briefly describes the basic principles of multi-criteria analysis (MCA) and cost–benefit analysis (CBA), in view of their application to the socio-economic evaluation of different scenarios for improving road safety. The specific scenarios for improving road safety by creating a more forgiving road (FOR) and self-explanatory road (SER) environment are, however, identified in subsequent chapters of this book. As regards MCA, the multi-actor MCA (or MAMCA), as well as the analytic hierarchy process (AHP), are discussed in more detail. As regard CBA, special attention is given to the definition of specific decision criteria. Special attention is also given to possible approaches to cope with lacking data on safety impacts. By the end of this chapter it should be very clear which are the different interpretations to be placed on the results of CBA and MCA, even in cases when these results are conflicting.