Noise Path Abatement

Noise Path Abatement Options

• Construction of noise barrier
• Noise walls, earth berms or a combination of the two.
• Reduce traffic noise levels by lengthening the noise path between source and receiver.

Alteration of horizontal alignment

• Changing roadway location or elevation to increase the noise path length between noise source and receiver to reduce noise levels.
• Option available only for Type I projects

Alteration of vertical alignment

• Alteration of the vertical alignment to take advantage of natural features to break line of sight between the noise source and receiver, similar to a noise barrier.

Effects of Vegetation

• Vegetation can provide aesthetic value and psychological relief from traffic noise.
• Vegetation is not used by FHWA or IDOT for traffic noise reduction because:

A. Vegetation would need to be at least 200 feet wide and 18 feet high to reduce noise levels by 10 dBA.

B. In most cases, available right-of-way cannot accommodate this width.