Loading...
BLD2023-1434+Noise_Report+11.9.2023_11.07.50_AM+3891440acoustics « Nelsen Esselstrorn October 17, 2023 John Scandola Camp & Associates, Inc. 19515 N. Creek Pkwy, Suite 220 Bothell, WA 98011 RECEIVED Nov 09 2023 CITY OF EDMONDS DEVELOPMENT SERVICES DEPARTMENT Re: Acoustical Report — Dish SESEA00147A Site: 10032 Edmonds Way, Edmonds, WA 98020 Dear John, BLD2023-1434 The following report presents a noise study for the proposed Dish telecommunications facility at 10032 Edmonds Way in Edmonds, Washington. This noise study extends from the proposed equipment to the nearest properties. The purpose of this report is to document the existing conditions and the impacts of the acoustical changes due to the proposed equipment. This report contains data on the existing and predicted noise environments, impact criteria and an evaluation of the predicted sound levels as they relate to the criteria. Code Requirements The site is located within the City of Edmonds Zoning jurisdiction on property with a WMU zoning in Residential use. There are WMU zoned properties in Commercial use to the north west, north and east. The Residential WMU property will be treated as Residential and the Commercial WMU property will be treated as Commercial. The receiving properties to the west and south are zoned Residential. The proposed new equipment consists of equipment support cabinets, which are expected to run 24 hours a day. Under Edmonds Municipal Code Chapter 5.30.040 noise from equipment on a Residential property is limited as follows: Residential Receiver: Noise is limited to 55 dBA during daytime hours. During nighttime hours, between the hours of 10 p.m. and 7 a.m., the maximum permissible sound level is decreased by 10 decibels. Since the support cabinets are expected to operate 24 hours a day, they must meet the 45 dBA nighttime limit. Commercial Receiver: Noise is limited to 60 dBA 24 hours a day. 7409 Greenwood Ave N, Suite A Seattle, WA 98103 206.839.0819 P // 206.839.0824 F Dish SESEA00180C Ambient Conditions Page 2 Existing ambient noise levels were measured on site with a Svantek 971 sound level meter on October 17, 2023. Measurements were conducted as close to the proposed location as possible and the property lines in accordance with the State of Washington code for Maximum Environmental Noise Levels WAC 173-60-020. The average ambient noise level was 66 dBA. Predicted Equipment Sound Levels 24 Hour Operation Equipment The following table presents a summary of the equipment and its associated noise level: Table 1: Equipment Noise Levels QuantityEquipment dBA (each) Charles CUBE—PM628151N4 65 dBA @ 5 ft 1 65 Total dBA (All cabinets combined) 65 Methods established by AHRI Standard 275-2010 and ASHRAE were used in predicting equipment noise levels to the receiving properties. Application factors such as location, height, and reflective surfaces are accounted for in the calculations. The equipment will be located on the rooftop approximately 44 feet above grade. The nearest Residential receiving property is approximately 75 feet southwest of the equipment, and the nearest Commercial receiving property is approximately 80 feet east of the equipment. The following table presents the predicted sound levels at the nearest receiving properties: Table 2: Predicted Noise Levels: Proposed Equipment Cabinets Line Application Fac or Resid. SW comm. E 1 Sound Pressure Level at 5 ft (dBA), Lp1 65 65 2 Noise Reduction — Parapet Reduction -10 -13 3 Distance Factor (DF) -24 -24 Inverse -Square Law (Free Field): DF = 20*log (d1/d2) (75 ft) (80 ft) 4 New Equipment Sound Pressure Level at Receiver, Lpr 31 28 (Add lines 1 through 3) As shown in Table 2, the sound level from the proposed equipment is predicted to be 31 dBA at the nearest Residential receiving property to the southwest, which meets the 45 dBA nighttime code limit. The sound level from the proposed equipment is predicted to be 28 dBA at the nearest Commercial receiving property to the east, which meets the 60 dBA code limit. Noise levels at other receiving properties, which are further away, will be lower and within code limits. Dish SESEA00180C Please contact us if you have any questions or require further information. Sincerely, SSA Acoustics, LLP Joshua Wah-Blumberg Technician Reviewed by: , x *, , 2,Io o � - Steven Hedback Acoustical Consultant Page 3 This report has been prepared for the titled project or named part thereof and should not be used in whole or part and relied upon for any other project without the written authorization of SSA Acoustics, LLP. SSA Acoustics, LLP accepts no responsibility or liability for the consequences of this document if it is used for a purpose other than that for which it was commissioned. Persons wishing to use or rely upon this report for other purposes must seek written authority to do so from the owner of this report and/or SSA Acoustics, LLP and agree to indemnify SSA Acoustics, LLP for any and all resulting loss or damage. SSA Acoustics, LLP accepts no responsibility or liability for this document to any other party other than the person by whom it was commissioned. The findings and opinions expressed are relevant to the dates of the works and should not be relied upon to represent conditions at substantially later dates. Opinions included therein are based on information gathered during the study and from our experience. If additional information becomes available which may affect our comments, conclusions or recommendations SSA Acoustics, LLP reserves the right to review the information, reassess anv new potential concerns and modifv our opinions accordingly.