Oregon Department of Transportation Traffic Noise Prediction Manual

About this manual

This document serves as the official guide for the Oregon Department of Transportation (ODOT) regarding highway traffic noise and construction noise. It details the implementation of the Federal Highway Administration (FHWA) Noise Standard, defining how ODOT identifies noise impacts and evaluates abatement measures for federal-aid highway projects. The manual covers the background of noise regulations, including the National Environmental Policy Act and the Federal-Aid Highway Act of 1970, and establishes ODOT's specific procedures for compliance.

What's inside

• Introduction
• Noise Standards
• Definitions
• Applicability
• Traffic Noise Prediction
• Analysis of Traffic Noise Impacts
• Analysis of Noise Abatement
• Construction Noise
• Documentation of Traffic Noise Study
• Noise Barrier Approval Process

Frequently asked questions

What is the minimum noise reduction required for an abatement measure to be considered feasible?

For an abatement measure to be feasible, ODOT requires that a simple majority of impacted receptors receive a minimum reduction of 5 dBA in noise levels.

What is the definition of a benefited receptor in the context of noise abatement?

A benefited receptor is the recipient of an abatement measure that receives a noise reduction of at least 5 dBA, regardless of whether or not the receptor is impacted.

Under what condition is a receiver considered impacted in Oregon?

In Oregon, a receiver is considered impacted when the future build alternative noise level is 2 dBA less than the corresponding FHWA noise abatement criteria.