Loading...
HomeMy WebLinkAboutEXCEPTIONti EDWARD L PACK ASSOCIATES AC. Consulting Engineers 1030 E. DUANE AVENUE, SURE F SUNNYVALE. CA 94086 Mr. Bob Dunnett Brookside Swim and Racquet Club 19127 Cox Avenue Saratoga, California 95070 TELEPHONE (408) 730.5574 September 7, 1989 Proiect No. 21 -083 Subject: Noise Assessment Study of the Brookside Swim and Racquet Club, Saratoga Ref.(a): Noise Ordinance of the City of Saratoga, Article 7 -30, Noise Control, Adopted August 1987 Dear Mr. Dunnett: This report presents the results of a noise assessment study of the Brookside Swim and Racquet Club in Saratoga. The noise levels presented herein were evaluated against the noise, standards of the City of Saratoga Noise Ordinance, Ref.(a), which specifies a noise level limit of 6 dBA above the local ambient at any point outside of the property plane. Sections I and II of this report contain our findings and evaluations, respectively. Appendix A, attached, contains noise data measured during a swim meet. I. Findings The findings presented below include the results of the noise level analysis and an evaluation against the standards of the City of Saratoga Noise Ordinance. MEMBER: ACOUSTICAL SOCIETY OF AMERICA AMERICAN SOCIETY OF SAFETY ENGINEERS AUDIO ENGINEERING SOCIETY INSTITUTE OF ENVIRONMENTAL SCIENCES - 2 - The standards specify a limit of 6 dBA above the local ambient. Measurements at several locations along.the tennis club and residential property lines indicated an ambient level of 48 dBA. Thus, the noise level limit at the residential property planes is 54 dBA. The noise levels shown below are without the application of mitigation measures. - The maximum noise levels measured at five locations along the east and north tennis club property lines ranged from 43 to 52 dBA. Thus, the noise levels produced by the club are in compliance with the City of Saratoga Noise ordinance. - The maximum noise levels measured at five locations along the east and north property lines of the club ranged from 48 to 58 dBA. Thus, the noise levels excedded the limits of the Saratoga poise Ordinance by 2 dB at two locations. - - To determine the noise impacts on surrounding residential areas, noise level measurements were taken at five locations along the east and north tennis club property lines.. - 3 - Measurements were made on August 31, 1989 using a Bruel and Rjaer 2231 sound analyzer. This test reflected typical weekday activities. Measurements were also made on July 8, 1989 using a Gen Rad Type 1933 sound analyzer. This test reflected typical weekend activities. Measurement Location 1 was approximately 100 ft. from the pool area. Locations 2 through 5 were approximately 40 ft. from the respective tennis court areas. The results of the measurements are shown in Table I, below. Location 1. Date and Peak Noise 31, 1989 Level. dBA August East of Pool July S. 1989 48 52 2. Bleachers at Easterly Tennis Courts 48 58 3. Northeast Corner of Tennis Courts 45 58 4. Water Fountain at North Property Line 44 56 5. Near Driveway at North Property Line 43 51 0 As shown above, three locations at the club are impacted by noise levels in excess of the standards. However, the residence nearest Location 2 is approximately 80 ft. away and behind the property line fence. Therefore, the peak noise level at this residence is 50 dBA and is in compliance with the standards. - 4 - The noise level at the northeast also 2 dB in excess of the standards. property line fence reduces the noise not a solid air -tight noise barrier. impacting the residence nearest the ni tennis courts is 56 dBA. i corner of the club site is However, the existing levels by 2 dB, as it is Thus, the peak noise level Drtheast corner of the Noise diminishes at a rate of 6 dB for each doubling of the distance from the source to the receiver. Therefore, locations at greater distances from the noise source receive lower noise levels. A difference of 3 dB is "just perceptible• to the human In conclusion, one residence along the northeast corner of the club is impacted by tennis club activities. As the exceedence level is 2 dB, the ensuing impact may not be noticeable. The noise levels presented are from field measurements and calculations and are correct to the best of our knowledge. However, changes in activities, apparatus, or equipment may . produce long -range noise levels different from our test results. - 5 - I! you have any questions or would like an elaboration of this report, please call me. Sincerely, EDWARD L. PACK ASSOCIATES, INC. Je r ac es -Went MC?: th Attachment: Appendix A The noise levels presented below were measured on June 24, 1989 during a semi - annual swim meet. The noise levels were measured using a Gen Rad Type 1933 sound analyzer, which was calibrated before and after the tests to assure accuracy. The noise levels were evaluated against the standards of the City of Saratoga Noise ordinance, which specifies a limit of 6 dB above the local ambient at the nearest property plane. The ambient noise level at the adjacent property planes is 48 dBA. Tho'standard for this evaluation is 54 dBA. The noise levels presented below are without the application of mitigation measures. M r. M-9 MUM7.777-MR5 - A maximum noise level due to activities at the club, at the nearest residential property plane, directly across Saratoga Creek from the pool and basketball court is 71 dBA._ The noise level is from-children performing cheers before the start of a semi - annual swimming meet and is 17 dB in excess of the standards. The whistle used to call the swim meet racers to the starting blocks produced a maximum level of 63 dBA at the nearest residential property plane. This level is 9 dB in excess of the standards. A -1 Individual tennis practicing against the practice wall produced levels up to 62 dBA. These levels are up to 8 dB in excess of the standards. The general noise of the swim meet produced levels up to 59 dBA at the nearest residential property plane. Thus, the levels are up to 5 dB in excess of the standards. Table II, below, shows the noise levels measured at five property line locations during the swim meet. Location on 1. East of Pool 2. Bleachers at Easterly Tennis Courts 3. Northeast Corner of Tennis Courts 4. Water Fountain at North Property Line 5.-Near Driveway at North Property Line 82 58 58 56 56 'Basketball playing produced noise levels up to 64 dBA at a 10 ft. distance. At the nearest residential property line, this level is reduced to 39 dBA. In conclusion, noise levels produced during the semi - annual swim meet are up to 17 dB in excess of the standards of the City of Saratoga Noise ordinance. A -2