PURPLE LINE EXTENSION SECTION 2 AMBIENT NOISE LEVEL REPORT METRO PROJECT RODEO STATION

Transcription

1 PURPLE LINE EXTENSION SECTION 2 AMBIENT NOISE LEVEL REPORT METRO PROJECT RODEO STATION Kleinfelder

2 Section Table of Contents 1.0 Introduction Noise Measurement Procedure Noise Measurement Analysis Noise Measurement Results Measurement Locations Weather Conditions Measurement Result Graphs Measurement Result Tables Page Table List of Tables Table 1 RD1: Beverly Wilshire Hotel Weekday Noise Measurement Results Table Table 2 RD1: Beverly Wilshire Hotel Weekend Noise Measurement Results Table Table 3 RD2: 202 North Beverly Weekday Noise Measurement Results Table Table 4 RD2: 202 North Beverly Weekend Noise Measurement Results Table Table 5 RD3: 121 South Beverly Weekday Noise Measurement Results Table Table 6 RD 3: 121 South Beverly Drive Weekend Noise Measurement Results Table Table 7 RD4: 9429 Wilshire Weekday Noise Measurement Results Table Table 8 RD4: 9429 Wilshire Weekend Noise Measurement Results Table Table 9 RD5: Reeves Park/133 South Reeves Weekday Noise Measurement Results Table Table 10 RD5: Reeves Park/133 South Reeves Weekend Noise Measurement Results Table Table 11 RD6: 190 North Cañon Weekday Noise Measurement Results Table Table 12 RD6: 190 North Cañon Weekend Noise Measurement Results Table Table 13 RD7: 9424 Wilshire Weekday Noise Measurement Results Table Table 14 RD7: 9424 Wilshire Weekend Noise Measurement Results Table Table 15 RD8: 120 South Reeves Weekday Noise Measurement Results Table Table 16 RD8: Weekend Noise Measurement Results Table Table 17 RD9: 9393 Wilshire Weekday Noise Measurement Results Table Table 18 RD9: 9393 Wilshire Weekend Noise Measurement Results Table Table 19 RD10: 121 South Cañon Weekday Noise Measurement Results Table Table 20 RD10: 121 South Cañon Weekend Noise Measurement Results Table Table 21 RD11: 9372 Wilshire Weekday Noise Measurement Results Table... Table 22 RD11: 9372 Wilshire Weekend Noise Measurement Results Table Page Figure List of Figures Figure 1: RD-1 Measurement Location Photo... 5 Figure 2: RD-2 Measurement Location Photo... 6 Figure 3: RD-3 Measurement Location Photo... 6 Figure 4: RD-4 Measurement Location Photo... 7 Figure 5: RD-5 Measurement Location Photo... 7 Page Page 2 of 78

3 Figure 6: RD-6 Measurement Location Photo... 8 Figure 7: RD-7 Measurement Location Photo... 8 Figure 8: RD-8 Measurement Location Photo... 9 Figure 9: RD-9 Measurement Location Photo... 9 Figure 10: RD-10 Measurement Location Photo Figure 11: RD-11 Measurement Location Photo Figure 12 Measurement Locations Map Figure 13 RD1: Beverly Wilshire Hotel Weekday Noise Measurement Results Graph Figure 14 RD1: Beverly Wilshire Hotel Weekend Noise Measurement Results Graph Figure 15 RD2: 202 North Beverly Drive Weekday Noise Measurement Results Graph Figure 16 RD2: 202 North Beverly Drive Weekend Noise Measurement Results Graph Figure 17 RD3: 121 South Beverly Weekday Noise Measurement Results Graph Figure 18 RD3: 121 South Beverly Weekend Noise Measurement Results Graph Figure 19 RD4: 9429 Wilshire Weekday Noise Measurement Results Graph Figure 20 RD4: 9429 Wilshire Weekend Noise Measurement Results Graph Figure 21 RD5: Reeves Park/133 South Reeves Weekday Noise Measurement Results Graph Figure 22 RD5: Reeves Park/133 South Reeves Weekend Noise Measurement Results Graph Figure 23 RD6: 190 North Cañon Weekday Noise Measurement Results Graph Figure 24 RD6: 190 North Cañon Weekend Noise Measurement Results Graph Figure 25 RD7: 9424 Wilshire Weekday Noise Measurement Results Graph Figure 26 RD7: 9424 Wilshire Weekend Noise Measurement Results Graph Figure 27 RD8: 120 South Reeves Weekday Noise Measurement Results Graph Figure 28 RD8: 120 South Reeves Weekend Noise Measurement Results Graph Figure 29 RD9: 9393 Wilshire Weekday Noise Measurement Results Graph Figure 30 RD9: 9393 Wilshire Weekend Noise Measurement Results Graph Figure 31 RD10: 121 South Cañon Weekday Noise Measurement Results Graph Figure 32 RD10: 121 South Cañon Weekend Noise Measurement Results Graph Figure 33 RD11: 9372 Wilshire Weekday Noise Measurement Results Graph Figure 34 RD11: 9372 Wilshire Weekend Noise Measurement Results Graph Page 3 of 78

4 1.0 Introduction This report provides results from ambient noise monitoring for the Purple Line Extension Section 2 (PLE2) at sensitive receivers around the construction area, located along Wilshire Boulevard from South El Camino to South Crescent in Beverly Hills, California. The monitoring was conducted from March 1 through March 7, The purpose of this ambient noise monitoring is to establish a baseline of noise levels prior to the anticipated third-party utility relocation construction and general project construction of the Metro PLE Noise Measurement Procedure The noise measurement procedures described in the Metro Construction Noise and Vibration Control Specification Section and the City of Beverly Hills Noise Ordinance Title 5, Chapter 1 were followed during monitoring. Noise measurements were made using Larson Davis Model 831 Type 1 (Precision) sound level meters and SoftdB Piccolo Type 2 sound levels meters that are capable of measuring and storing L eq(t) 1 and other statistical noise levels over consecutive time periods. The meters were set to log the sound level once per second; 15-minute interval data was then calculated. The meter used the slow response and A-weighting. 2 The microphone was positioned at least five feet above grade, calibrated using an acoustic calibrator before and after each measurement and fitted with a wind screen. Monitoring locations were selected in coordination with the City of Beverly Hills as well as a knowledge of the scope of the utility relocation and subway/station design-build work. Detailed measurement location information is contained in Section Noise Measurement Analysis The noise measurement data was downloaded from the sound level meters into an Excel spreadsheet and graphs of the L eq(15-min) data over time were developed. This allowed the inspection of the data to determine the existence of data points that were considered outliers (noise levels that were considerably above the levels recorded for the other days at the same time or where the level suddenly increased and then dropped back down, indicating an unusual event) that should be excluded from further evaluation. Given the small sample size, such outliers would skew the average and standard deviation if included. These outliers may be attributed to an unusually noisy vehicle, a siren, adjacent construction activity (not Metro related) or other non-normal event. Within each 15-minute period, a range of three to over five decibels from one day to the next (i.e., across all data points for that interval) was observed. A statistical analysis was then performed to determine the upper bound of the ambient noise level. The analysis included determining the average and standard deviation for each 15-minute period. We assumed a normal distribution and a one-sided 90% confidence level to determine the ambient noise level representing the 90% upper limit. There is a 90% probability that the ambient does not exceed this value; this analysis methodology is used to remain consistent with previous Metro ambient noise reports. 1 L eq(t): The equivalent steady-state A-weighted sound level that, in a stated period of time, would contain the same acoustic energy as the time-varying sound level during the same time period. 2 A-weighting: A standard frequency weighting that filters the microphone signal in a manner which compares relative loudness of various sounds. A-weighting is standardized by the American National Standards Institute (ANSI). A 10-dB increase in sound level is generally perceived to be approximately twice as loud. All noise data in this report are A-weighted. Page 4 of 78

5 The average of the 15-minute period standard deviations, σ t, for the nighttime period was determined. From these values, the level representing the 90% confidence limit of the ambient L eq(15-min) noise was calculated as follows: L eq(15-min)90% Limit = L eq(15-min) * σ ave (the z-value for the one-sided lower confidence of 90% is 1.282). We have also included the L eq(15-min)90% Limit + 5 db and the L eq(1-hr)90% Limit + 5 db compliance values to remain consistent with previous Metro ambient noise reports. 4.0 Noise Measurement Results This section presents a brief description of the measurement sites and provides graphs showing the L eq(15-min) noise levels for each 15-minute period, and the 90% confidence values for the ambient L eq(15-min), the ambient L eq(15-min) + 5dB compliance value, and the ambient L eq(1-hr) + 5 db compliance value. Also included are tables of the 90% confidence limits for the ambient L eq(15-min), the ambient L eq(15-min) + 5 db compliance value, and the ambient L eq(1-hr) + 5 db compliance values. 4.1 Measurement Locations Measurements were conducted at eleven receivers in the vicinity of the proposed to document ambient (non-construction) noise levels. Both weekday and weekend measurements were conducted, as noise levels are significantly lower on the weekend. The first set of measurements was a 72-hour period during weekdays, and the second set was a 60-hour period during the weekend. The measurement locations are mapped in Figure 12. A brief description of the measurement locations follows: RD1 Beverly Wilshire Hotel: Noise measurements were conducted from March 1 to March 7, 2017 at the eastern edge of the Beverly Wilshire Hotel (9500 Wilshire Blvd). The microphone was located outside the property line 12 feet above grade on the sidewalk, 17 feet from the centerline of South El Camino Drive. The main noise source in the area was vehicular traffic on Wilshire Boulevard as well as South El Camino Drive. The results of the measurements are presented in Figures 13 and 14, as well as Tables 1 and 2. Figure 1: RD-1 Measurement Location Photo Page 5 of 78

6 Figure 12 Measurement Locations Map 4.2 Weather Conditions From March 1 through 7, 2017, the maximum wind speed was 16 miles per hour (mph), with an average speed of 6 mph. Wind was between 10 and 16 mph during afternoon/evening rush hour on two occasions. Traffic noise was significantly higher than any wind-generated noise; therefore, wind noise did not affect the measurement. The temperature ranged from a low of 47 F to a high of 78 F, while the average was 58 F. The humidity ranged from a low of 10% to a high of 100%, averaging 54% with 0.04 of precipitation around noon on March 5, The scant precipitation did not affect the measurement data. 4.3 Measurement Result Graphs The remainder of this report are the graphs and tables of results as described in Section 4.0. Page 11 of 78

7 Figure 13 RD1: Beverly Wilshire Hotel Weekday Noise Measurement Results Graph Page 12 of 78

8 4.4 Measurement Result Tables Table 1 RD1: Beverly Wilshire Hotel Weekday Noise Measurement Results Table Period Start Time Ambient Leq(15-min), Ambient Leq(15-min) + 5, 19: : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : Ambient Leq(1-hr) + 5, Page 34 of 78

9 Period Start Time Ambient Leq(15-min), Ambient Leq(15-min) + 5, 7: : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : Ambient Leq(1-hr) + 5, Page 35 of 78