Any increase or decrease in noise caused by a transportation improvement project has an economic value.
Examples
- A new onramp is added to a freeway, increasing noise around the onramp.
- An airport changes its flight paths, creating more flyovers in a residential neighborhood.
- A sound wall is built between a busy street and a residential neighborhood to reduce noise in the neighborhood.
Approach
- Estimate how much noise there will be at each affected location for each project alternative compared to the base case.
- If the amount of noise is high, consider whether noise abatement measures are needed.
- Determine the cost of noise abatement, and include it in the cost of the corresponding alternatives.
- Determine the value of the net change in noise levels for each project alternative (after any noise mitigation measures are taken). If noise is significantly decreased or increased, its net value is included as a benefit (or disbenefit).
Traffic noise is more than a nuisance. Researchers have found that excessive noise can impair people's hearing, disturb their sleep, and harm their overall sense of well-being. In addition, increases in traffic noise can reduce the property value of nearby homes.
When a transportation project has the potential to add significant amounts of traffic to an area, a traffic noise analysis may be required to determine the project's noise impact. If the impact is significant, the costs of noise abatement measures, such as sound walls, may need to be included as part of the cost-benefit analysis.
It is difficult to assign a dollar value to noise impacts, and the difference in noise between project alternatives may be small. For most projects, it is sufficient to estimate how much noise there will be when the project is complete, choose appropriate abatement methods, and include the cost of abatement in the cost of the project.
For very large projects that drastically increase noise (such as a new freeway built in a residential neighborhood) or reduce noise (such as construction of a sound wall), it may be appropriate to use a hedonic price model or a contingent valuation study.
Sources
Becker, N. and D. Lavee. "The Benefits and Costs of Noise Reduction." Journal of Environmental Planning and Management 46(1), 2003, pp. 97-111.
Berglund, B., T. Lindvall, and D. H. Schwela (ed.), Guidelines for Community Noise. World Health Organization, 2002.
California Department of Transportation (Caltrans). "Some Frequently Asked Questions About Highway Traffic Noise Analysis & Abatement." Available at: http://www.dot.ca.gov/hq/env/noise/pub/FAQ.pdf.
Hendriks, R.Technical Noise Supplement: A Technical Supplement to the Traffic Noise Analysis Protocol. California Department of Transportation (Caltrans), October 1998. Available at: http://www.dot.ca.gov/hq/env/noise/pub/Technical%20Noise%20Supplement.pdf.
Federal Highway Administration. Highway Traffic Noise Analysis and Abatement Policy and Guidance. Federal Highway Administration Office of Environment and Planning, Noise and Air Quality Branch, June 1995. Available at: http://www.fhwa.dot.gov/environment/polguid.pdf
Navrud, Ståle. "State-of-the-Art on Economic Valuation of Noise." Paper presented at the WCE/WHO Pan-European Program on Transport, Health, and Environment, Stockholm, June 2003. Available at: http://www.fhi.se/pdf/navrud.pdf
Nijland, H.A., E.E.M.M. Van Kempen, G.P. Van Wee, and J. Jabben. "Costs and Benefits of Noise Abatement Measures." Transport Policy 10, 2003, pp.131-140.
Schomer, Paul. "Assessment of Noise Annoyance." Schomer and Associates, April 2001. Available at: http://www.nonoise.org/library/schomer/assessmentofnoiseannoyance.pdf.