Use of Vegetation for Abatement of Highway Traffic Noise

Abstract

The high cost of conventional highway noise abatement methodology (i.e., free‐standing walls) has made mitigation of many impacted sites economically infeasible. A solution that may prove more economically reasonable for those sites is the use of strategically planted evergreen vegetation to form a dense barrier between the highway and impacted area. Field measurements were made on vegetative barriers planted only for visual screening purposes. The results of these measurements indicate that a 2 to 3 dB decrease in noise levels is possible with a narrow [30 ft (9.1 m)] belt of vegetation. These measurements are supported by the literature review, which indicates that an even further reduction may be possible with a barrier planted and maintained in such a way as to encourage maximum density growth. When coupled with the non‐quantifiable psychological effects of blocking the highway from view, and the low construction cost, the potential for solving uneconomical abatement problems is clear.