Tacoma Narrows Bridge Project


Construction of a bridge is a 24 hour, on-going operation consisting of heavy trucks, concrete booster pumps and front-end loaders. We made sure that the project adheres to the limits established by the Federal Highway Administration (FHA) and are based on activity categories for various land uses. Sound level measurements were taken using a Larson-Davis 820 Environmental Noise Monitor, Type 1 Instrument (ANSI S1.4, DIN IEC 651,804); two types of measurements were made to document the noise level exposure to the residents at nearby apartments. The first set of measurements was made for comparison with the FHA, 23 CFR Part 772 and Procedures for Abatement for Highway Traffic Noise and Construction Noise. Secondary measurements were made to verify the noise monitoring and mitigation methods outlined by the WDOT, Tacoma Narrows Bridge Project Operations Plan for Nighttime Construction Noise. Results indicated that the noise from the construction was exceeding the limits set by FHA. We took the necessary measures in order to reduce the effects of noise on surrounding properties.


Truck Traffic 24-hours a day


Fixed monitors and random monitoring of construction