Agda Pkt 2024.11.25. Joint SA PFA

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11/15/24 (P:\M-S\RWC2101.04 Docktown CE\PRODUCTS\Docktown_CEMemo_20241115.docx) 19 Deconstruction-related short-term noise levels would be higher than existing ambient noise levels currently in the project area but would no longer occur once deconstruction of the project is completed. This analysis assumes that a crane, dump truck and chain saw would be operating simultaneously during construction activities. Based on typical construction equipment noise levels (Lmax) recommended for noise impact assessments obtained from the Federal Highway Administration (FHWA) Roadway Construction Noise Model 13, noise levels associated with these pieces of construction equipment operating simultaneously would be approximately 85 dBA Lmax at 50 feet. The City of Redwood City regulates noise in the City’s Municipal Code.14 Section 24.30 through 24.34, Excessive and Unreasonable Noises apply to construction noise. This ordinance limits construction and demolition activities to the hours of 7:00 a.m. to 8:00 p.m. on weekdays when activities are occurring within a residential district. Construction and demolition activities are not permitted on weekends within a residential district. The ordinance also limits noise levels generated by an individual item of equipment to no more than 110 dB measured within a residential district of the City at any distance of 25 feet from the equipment. Any construction site within 500 feet of a residential area must post a sign at all entrances to the work site prior to commencement of the work for the purpose of informing all contractors and subcontractors and all other persons at the property of the basic limitations upon noise and construction activities provided in the noise ordinance. The closest sensitive receptors include the One Marina condominium development located approximately 150 feet north of the project site. At 150 feet, there would be a decrease of approximately 10 dBA from the increased distance compared to the noise level measured at 50 feet from the active construction area. Therefore, the closest sensitive receptor may be subject to short-term maximum construction noise reaching 75 dBA Lmax during construction. In addition, due to noise attenuation, this noise level would be below the City’s construction noise standard of 110 dBA at 25 feet. As identified in the Project Description, de-construction activities would occur during daytime hours, which would comply with the City’s Municipal Code. The project site is located within the Mixed Use Water zoning district, which, while not specifically a residential district, does permit housing. Consistent with Section 24.32.C of the City’s Municipal Code, the City’s Building Official or their designee may approve construction work occurring outside the allowed construction times. Prior to construction, the City would request approval for work to occur during the daytime hours on the weekends. Therefore, construction noise impacts would be less than significant. After deconstruction, the proposed project would not result in an increase in the vehicle trips and would not be a source of operational noise. Therefore, the proposed project would not expose persons to noise levels in excess of local standards. Operational noise impacts would be considered less than significant. Typical sources of groundborne vibration are construction activities (e.g., pavement breaking and operating heavy-duty earthmoving equipment), and occasional traffic on rough roads. In general, groundborne vibration from standard construction practices is only a potential issue 13 Federal Highway Administration (FHWA). 2006. Roadway Construction Noise Model. 14 Redwood City, City of, 2017. City Code of Redwood City, California. April 26. 6.G. - Page 23 of 45 201