Hotel Angeleno Noise Measurements

Kiewit Infrastructure West Co. added a 10-mile high-occupancy vehicle (HOV) lane on the northbound I-405 between the I-10 and U.S. 101 freeways.  The Hotel Angeleno is adjacent to the Sunset Boulevard Bridge, which was scheduled for partial demolition and reconstruction.  To evaluate the noise impact of demolition and pile-driving, UltraSystems conducted specialized frequency-specific noise measurements on the interior and exterior of the hotel to assess the existing attenuation provided by the building’s structure and room features.  UltraSystems prepared a detailed noise report that included a sound measurement database for all the frequency-noise charts, a frequency distribution data table, and a noise attenuation-by-frequency table.  In addition, UltraSystems reviewed the literature on the frequency distribution of pile driving noise. The hotel structure’s existing attenuation in each frequency band comprising the pile driving noise emissions was then determined.  It was determined that the attenuation would not be sufficient to render noise exposures to hotel residents less than significant during pile driving.  UltraSystems identified a variety of mitigation strategies.  The project proponent elected to lease the affected hotel rooms to avoid noise impacts to the public during pile driving.