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2.3_Chapter 2.3 - NoiseSection 2.3 Noise Section 2.3 – Noise Espola Road Improvement Project Final EIR 2.3-1 May 2013 2.3 NOISE This section presents an assessment of potential noise impacts associated with the proposed Project. The evaluation addresses potential noise and vibration created during the construction of the Project and operational noise from the widened roadway on adjacent noise-sensitive land uses. The analysis is based on information contained within the Noise Study Report (included as Appendix B of this EIR) prepared for the Project by HELIX (2011). Noise criteria and policies established in the City General Plan Noise Element (1991a) and Municipal Code, as well as Section 216 of the California Streets and Highways Code are followed in this section. These standards establish procedures for noise studies regarding traffic noise prediction, noise analyses and noise abatement criteria. 2.3.1 Affected Environment Noise Descriptors Sound (noise) levels are measured in decibels (dB). Community noise levels are typically measured in terms of A-weighted decibels (dBA). The A-weighted scale measures noise levels generally corresponding to the human hearing frequency response. All sound levels in this EIR are A-weighted. In general, vehicular noise levels increase with speed. Assuming that traffic speeds remain the same, increased traffic volumes also can increase traffic noise. In general, with traffic moving at the same speed, it takes a doubling of the traffic volume to increase noise levels by three dBA. Sound propagation (i.e., the passage of sound from a noise source to a receiver) is influenced by several factors. The manner in which noise reduces with distance depends on several factors, including geometric spreading and ground absorption, as well as shielding by natural and human- made features. In general, the greater the distance the receiver is situated from the road, the greater the potential for variation in noise levels due to the atmospheric effects. Additional noise attenuation can result from human-made features, such as buildings and walls, as well as natural features, such as hills and dense vegetation, which can reduce traffic noise by shielding the receiver from the road. Atmospheric effects also can influence traffic noise. These effects include wind, temperature gradients, and humidity. Additional units of measurement have been developed to evaluate the long-term characteristics of sound. The equivalent sound level (Leq), also referred to as time-average sound level, is a single number representing fluctuating sound level in dB over a specified period of time (e.g., one minute, 10 minutes, one hour). The Leq also is used to determine the Community Noise Equivalent Level (CNEL) used by the City to describe community noise levels. CNEL is a weighted 24-hour average sound level (i.e., the sound-energy average value of 24 hourly Leq after applying a 5-dB “penalty” to noise levels from 7:00 p.m. to 10:00 p.m. and a 10-dB penalty from 10:00 p.m. to 7:00 a.m.). The 5- and 10-dB penalties are applied to account for increased sensitivity of people exposed to noise during the evening and nighttime hours. Section 2.3 – Noise Espola Road Improvement Project Final EIR 2.3-2 May 2013 Methodologies and Instrumentation To determine existing noise levels and provide the basis for identification of potential noise impacts, a noise monitoring survey was conducted along the Project alignment. Although all developed land uses were evaluated in the Noise Study Report, noise abatement was only considered for areas of frequent human use that would benefit from a lowered noise level (i.e., outdoor activity areas, such as residential backyards and institutional open space areas). Noise measurements were conducted using a Larson-Davis Laboratories Model 700 (S.N. 2132) integrating sound level meter equipped with a Type 2551 0.5-inch pre-polarized condenser microphone with pre-amplifier. When equipped with this microphone, the sound level meter meets the current American National Standards Institute Standard for a Type 1 (precision) sound level meter. The sound level meter was calibrated before and after each measurement and the measurements were conducted with the microphones positioned five feet above the ground level. The traffic model used is the Traffic Noise Model (TNM) software Version 2.5, specifically developed to assess noise related to roadways. TNM calculates the daytime average Hourly Noise Level (HNL) from three-dimensional model inputs and traffic data. The TNM models used in this analysis were developed from the project planning Computer Aided Design (CAD) model features, including road alignment, elevation, lane configuration, area topography, existing and planned noise control features, projected traffic volumes, estimated truck composition percentages, and vehicle speeds. Traffic noise was evaluated under existing conditions, design-year No Project conditions and design-year conditions with the proposed Project. Loudest-hour (peak) traffic volumes, vehicle classification percentages, and traffic speeds under existing and design-year (2030) conditions were provided by the Project traffic engineer (KOA Corporation 2006). The loudest hour is generally characterized by free-flowing traffic at the roadway design speed (i.e., generally equivalent to LOS C or better). The analysis for the Noise Study Report is based on these peak traffic volumes at the roadway maximum potential future speed of 45 miles per hour. The truck percentage used in the noise model for the loudest (peak) hour average sound level was 1.9 percent medium trucks and 0.2 percent heavy trucks. Espola Road is restricted to vehicles weighing 20,000 pounds or less, which restricts the amount of truck traffic. Estimated truck composition percentages used in the noise model are based on the traffic mix counted during on-site noise measurements; the truck mix is assumed to remain the same in the future. TNM 2.5 was used to compare measured traffic noise levels to modeled noise levels at noise measurement locations in order to validate the accuracy of the model. For each receiver, traffic volumes counted during the short-term measurement periods were normalized to one-hour volumes. These normalized volumes were assigned to simulate the noise source strength during the actual measurement period. Modeled and measured sound levels were then compared to determine the accuracy of the model and if additional calibration of the model was necessary. Section 2.3 – Noise Espola Road Improvement Project Final EIR 2.3-3 May 2013 Existing Noise Levels In order to ensure that modeling would reflect real-world conditions, noise measurements were completed at a number of site locations. These included actual sound measurement, as well as counting of vehicle numbers and types passing by the location. The existing readings were then compared with projected sound levels generated through modeling of counted vehicular numbers, existing topography, and measurement location (shown in Table 2.3-1, Measured Average Noise Level and Concurrent Traffic Volumes).1 Table 2.3-1 MEASURED AVERAGE NOISE LEVEL AND CONCURRENT TRAFFIC VOLUMES Site Description Date/Time Leq2 Cars MT3 HT4 M11 South of Twin Peaks Road approximately 50 feet to centerline of Espola Road October 31, 2002/ 1:40 - 2:00 p.m. 66 dBA 253 3 2 M2 West of Mountain Road approximately 45 feet to centerline of Espola Road October 18, 2002/ 10:20 - 10:40 a.m. 66 dBA 213 7 2 M3 South of Del Poniente Road approximately 45 feet to centerline of Espola Road October 31, 2002/ 4:00 - 5:00 p.m. 66 dBA 1,834 36 3 M4 South of North Crest Lane approximately 75 feet to centerline of Espola Road October 18, 2002/ 11:20 - 11:40 a.m. 54 dBA 229 5 0 M5 North of Twin Peaks Road approximately 70 feet to centerline of Espola Road October 18, 2002/ 10:45 - 11:05 a.m. 63 dBA 262 8 2 M6 Montessori Child Development Center approximately 150 feet to centerline of Espola Road October 18, 2002/ 9:40 - 10:00 a.m. 56 dBA 250 7 2 M7 South of Eden Grove approximately 95 feet to centerline of Espola Road October 31, 2002/ 2:55 - 3:15 p.m. 64 dBA 541 7 1 1 This technical effort ensures that when noise projections are made, appropriate and accurate data have been integrated into the model (if modeling does not match the existing, real-world measurements, the model is adjusted until it does match existing parameters). The actual date of original modeling is not relevant to ultimate projections, because those projections do not incorporate existing sound levels and then add on to them, but rather “stand on their own.” In other words, given details about assumed traffic mix, traffic numbers and time of day, combined with details as to planned road elevational changes due to grading, changes in lane configuration, and location of sensitive receptors, the model will accurately project future conditions. Section 2.3 – Noise Espola Road Improvement Project Final EIR 2.3-4 May 2013 Table 2.3-1 (cont.) MEASURED AVERAGE NOISE LEVEL AND CONCURRENT TRAFFIC VOLUMES Site Description Date/Time Leq2 Cars MT3 HT4 BG1 Approximately 50 feet to centerline of Durhullen Drive and 0.25 mile west of site October 31, 2002/ 3:30 - 3:50 p.m. 51 dBA 28 0 0 BG2 Approximately 50 feet to centerline of Twin Peaks and 0.25 mile west of site November 13, 2002/ 7:05 - 7:35 a.m. 70 dBA 808 18 5 Source: Pacific Noise Control 2004 Notes: 1 Refer to Figure 2.3-1 for a graphic depiction of noise monitoring locations M1 through M7. 2 Equivalent continuous A-weighted sound pressure level 3 Medium trucks 4 Heavy trucks Short-term noise measurements were made at nine locations. Noise measurements were conducted for periods of 20 to 60 minutes adjacent to the road at seven locations (designated as Sites M1 through M7 on Figure 2.3-1, Noise Measurement and Noise Receiver Locations). Two background noise measurements were conducted outside the Espola Road corridor to determine the contribution of traffic noise to the existing noise levels. Additionally, one long-term noise measurement was taken over the course of one full day. The measured noise levels at Sites M1 through M7 varied from 54 to 66 dBA Leq. The results of the noise level measurements and corresponding traffic counts are depicted in Table 2.3-1. Background noise measurements were conducted approximately 50 feet from the centerlines of Durhullen Drive and Twin Peaks Road (Sites BG1 and BG2, respectively, in Table 2.3-1), approximately 0.25 mile west of the Project site. Background noise levels generally range from approximately 45 to 50 dBA within residential areas located approximately 0.25 mile from the Project site. The noise level was approximately 50 dBA Leq along Durhullen Drive (a two-lane local collector) and the noise level was approximately 70 dBA Leq along Twin Peaks Road (a four- lane major arterial). In addition to short-term noise measurements, a single long-term measurement site (Site A) was selected to capture the diurnal traffic noise level pattern in the Project area and provide an unobstructed view of the road (i.e., no intervening walls, buildings, vegetation, etc.). The purpose of this noise measurement was to determine the typical peak loudest hour Leq associated with traffic along Espola Road and the corresponding relationship between the loudest hour and CNEL. The predicted sound levels were within two dBA of the measured sound levels and were, therefore, considered to be in reasonable agreement with the measured sound levels. As such, no additional calibration of the model was required. !9 !8 !M7 !34 !33 !32!31 !30 !29 !28 !53 !52 !51 !50 !49 !48 !47 !46 !45 !44 !43 !42 !41 !40 !39 !38 !37 !36 !35 !27 !26 !25 !24 !M1 !23 !22 !21 !20 !19 !18 !17 !16 !15 !14 !13 !12 !11 !10 !M6 !M5 !M3 !M2 !M4 !A !BG1 !BG2 !23A E s p o l a R o a d Twin Peaks Road Mtn Road Northcrest Lane Titan Way Del Poniente Road Huntington Gate Drive Tierra Bonita Road Eden Grove Via Molinero Golden Sunset Lane Derringer Road Carlson Street Kalapana Street Jerome Drive Roberto Rio Road R i d g e v i e w P l a c e Crestview Court Durhullen Drive Rio Court Mesquite Tree Evergreen Lane El Topo Drive Los Nietos Avenue Segundo Court Carnitas StreetEl Dolora Way H i g h V a l l e y R o a d Saddlebrook Court Alando Place Espola Road Willow Ranch Road Job No: BAH-01 Date: 12/22/11 µ I:\Gis\B\BAH-01Espola Rd\Map\EIR\Fig2-3-1_Noise_Receivers.mxd -JP 500 0 500250Feet Figure 2.3-1 ESPOLA ROAD IMPROVEMENT PROJECT Noise Measurement and Noise Receiver Locations LEGEND !A !1 Noise Receiver Location Short-term Background Noise Measurement Location Long-term Noise Measurement Location Short-term Noise Measurement Location !BG1 !M1 Section 2.3 – Noise Espola Road Improvement Project Final EIR 2.3-5 May 2013 Regulatory Setting State Section 216 of the California Streets and Highways Code Section 216 of the California Streets and Highways Code relates to roadway noise effects on public and private elementary and secondary schools. Under this code, a noise impact would occur if, as a result of a proposed project, noise levels would exceed 52 dBA Leq(h) in the interior of public or private elementary or secondary classrooms, libraries or multi-purpose rooms or spaces. If a project results in a noise impact under this code, noise abatement must be provided to reduce classroom noise to a level that is at or below 52 dBA Leq(h). If the noise levels generated from freeway and non-freeway sources exceed 52 dBA Leq(h) prior to the construction of the proposed freeway project, then noise abatement must be provided to reduce the noise to the level that existed prior to construction of the project. City of Poway City of Poway General Plan To facilitate implementation of noise abatement measures, the City uses the following general noise abatement guidelines for residential areas next to existing arterials for road improvement projects: 1. When improvements to arterials are constructed in developed areas where the existing noise level is below 60 dB CNEL, noise levels will be mitigated to 60 dB CNEL provided a noise attenuation wall does not exceed eight feet. If the proposed noise attenuation wall exceeds eight feet, the City will strive to reduce noise to the best practical level. 2. In areas where the existing noise level exceeds 65 dB CNEL, the noise level will be mitigated to 65 dB CNEL. Although not specifically stated in the City’s General Plan, the City also will strive to reduce noise levels to 60 dB CNEL in areas where the existing noise level is between 60 and 65 dB CNEL. In identifying noise impacts, primary consideration is given to exterior areas of frequent human use. The noise abatement criteria for outdoor noise exposure typically are applied at the backyards of single-family homes. City of Poway Municipal Code Noise-generating sources in the City are regulated under Chapter 8.08, Noise Abatement and Control, of the PMC. PMC Section 8.08.100 restricts the allowable hours of construction activities to 7:00 a.m. through 7:00 p.m., Monday through Saturday, excluding legal holidays. Section 2.3 – Noise Espola Road Improvement Project Final EIR 2.3-6 May 2013 This ordinance states that the operation of any single or combined powered construction equipment is prohibited before 7:00 a.m. or after 5:00 p.m. on Mondays through Saturdays or at any time on a Sunday or holiday, except as permitted by the City Engineer. Further, the noise levels associated with construction activities at residential properties are not to exceed 75 dBA, averaged over an eight-hour period per day. Equipment noise levels must comply with the limits over various durations as shown in Table 2.3-2, City of Poway Noise Requirements. Table 2.3-2 CITY OF POWAY NOISE REQUIREMENTS Total Duration in 24 Hours Total Decibel Level Up to 15 minutes 90 Up to 30 minutes 87 Up to 1 hour 84 Up to 2 hours 81 Up to 4 hours 78 Up to 8 hours 75 Source: City PMC Chapter 8.08 2.3.2 Thresholds of Significance The Project would result in significant impacts associated with noise if it would:  Expose persons to or generation of noise levels in excess of standards established in the local general plan or noise ordinance, or applicable standards of other agencies.  Expose persons to or generation of excessive groundborne vibration or groundborne noise levels.  Result in a substantial permanent increase in ambient noise levels in the Project vicinity above levels existing without the Project.  Result in a substantial temporary or periodic increase in ambient noise levels in the Project vicinity above levels existing without the Project. 2.3.3 Impacts Construction Impacts During construction of the Project, noise from construction activities may intermittently dominate the noise environment in the immediate area of construction. Noise generated during construction would occur with varying intensities and durations during the different phases of construction: clear and grub, earthwork, base preparation, paving and cleanup. The City’s construction noise criteria are that the noise levels associated with construction activities at residential properties should not exceed 75 dBA, averaged over 8 hours during any 24-hour period. Section 2.3 – Noise Espola Road Improvement Project Final EIR 2.3-7 May 2013 Project construction activities would result in a short-term, temporary increase in the ambient noise level in the immediate area of construction. The magnitude of the impact is dependent upon the type of construction activity and equipment generating the noise, the duration of the construction stage, and the distance between the noise source and the receptor. Heavy equipment is expected to include at least two large earthmovers, two graders, two large dump trucks, two concrete trucks/mixers and two large loaders. Tractors, backhoes, skid steers, paver/rollers, and water trucks also would be utilized. The heavy equipment has been estimated conservatively to be in operation eight hours per day and six days per week. Construction equipment would be expected to generate noise levels ranging from 70 to 90 dBA at a distance of 50 feet. Noise generated by construction equipment would be reduced over distance at a rate of approximately 6 dBA per doubling of distance away from the source (Harris 1998). With implementation of standard noise abatement features, such as mufflers, the grading and paving construction activities are anticipated to generate noise levels that comply with the City’s noise criteria. There is a relatively small potential that blasting could be required in areas of shallow bedrock, and some large rocks are present in the vicinity of Northcrest Lane on the east side of Espola Road. (It is possible that the rocks may be broken rather than blasted apart.) If blasting is necessary, these operations would precede other roadway grading activities and would be completed in a relatively short time period. Any rock produced during blasting activities would be hauled off site or buried on site fills. No crushing would occur on site. Construction blasting can generate maximum noise levels of approximately 94 dBA at a distance of 50 feet (Bolt Beranek and Newman 1989). The specific blasting hole sites are not known. Because of the infrequent nature of blasting (i.e., approximately one or two blasts per day), however, this noise level would be less than significant at residences located more than approximately 50 feet from the blast area with proper pre-blast notices to the residents. Blasting from construction projects generates a velocity level of approximately 100 dBA or a peak particle velocity of approximately 0.80 inch per second (Federal Transit Administration 2006). At a distance of 65 feet from the blast, the peak particle velocity would be approximately 0.20 inch per second. This vibration level is the limit that is typically considered acceptable for all building structures along the Project site. Thus, if blasts are proposed to be conducted within 65 feet of residences, the blasting contractor may be required to implement additional blasting control measures. With required adherence to the PMC regulations governing the acceptable hours of construction, no significant impact is identified. Operational Impacts Typically, the peak hour Leq noise level along surface streets is approximately equal to the CNEL value where the peak hour is between 8 and 12 percent of the ADT. This assumption was Section 2.3 – Noise Espola Road Improvement Project Final EIR 2.3-8 May 2013 confirmed during a 24-hour noise measurement for the Project. Future traffic noise levels have been projected under existing and design year conditions (with and without the proposed Project). Table 2.3.3, Predicted Future Noise and Barrier Effectiveness Analysis, illustrates the difference between existing conditions and the future conditions without Project improvements to set baseline data. The table also identifies what the decibel change would be with proposed improvements to the three-lane width for each of the receptor locations mapped on Figures 2.3-1 and 2.3-2, Noise Receivers and Proposed Noise Barrier Locations. Following that, Table 2.3-3 identifies whether the sensitive receptors contain a protected use area, and if so, the height of wall recommended to provide appropriate attenuation of roadway noise under City criteria. Where residences have existing sound walls (Barriers B1-S and B1-N) along Espola Road, computer modeling for the future Project-related noise impacts take them into account to determine whether the existing walls would provide sufficient noise control. Due to the roadway traffic volumes and speeds, the traffic noise impacts do not extend to any residents beyond the single-family residences directly along Espola Road. The future loudest hour Leq would generally range from approximately 55 to 69 dBA at the usable outdoor space (generally backyards) of residences without existing sound walls located adjacent to Espola Road. The future noise level would exceed City thresholds at a number of identified receivers with protected outdoor use areas (i.e., Sites 8-14, 18-20, 24-27, 35, 38-39, 42 and 44 on Figure 2.3-1) along Espola Road. Potentially significant impacts are identified to each of these receptors, and sound barriers are proposed as shown on Table 2.3-3. Some homes have front yards bordering Espola Road, but also have usable outdoor space (generally backyards) shielded from Espola Road traffic noise by the intervening home, topography, or other structures. These include Sites 15-17, 21-23, 41 and 45-52. No significant impacts are identified to the front yards in these cases because usable outdoor space is provided in the backyards. Two homes (Sites 37 and 43) are located on large lots. These homes have apparent use areas in the front or side yards. Substantial lot area exists around these homes that would allow for exterior use areas shielded by the homes. No significant impacts are identified. The Montessori Child Development Center (Site M6) would be subject to a future loudest hour Leq of approximately 64 dBA. This noise level would comply with the City noise significance threshold. Section 216 of the Streets and Highways Code also requires abatement for noise that intrudes into specified areas of elementary or secondary schools when the levels within these areas exceed a one-hour average sound level of 52 dBA. The classrooms at the school adjacent to Espola Road have air conditioning; this condition allows the classrooms to shut their windows, operate the air conditioners, and reduce roadway noise in the classrooms. Assuming a minimum noise reduction of 20 dBA with closed windows, the interior future loudest hour Leq would be approximately 44 dBA at the closest classrooms. This noise level would comply with the noise significance threshold and no operational noise impacts from the proposed Project would occur. !9 !8 !34 !33 !32!31 !30 !29 !28 !53 !52 !51 !50 !49 !48 !47 !46 !45 !44 !43 !42 !41 !40 !39 !38 !37 !36 !35 !27 !26 !25 !24 !23 !22 !21 !20 !19 !18 !17 !16 !15 !14 !13 !12 !11 !10 !23A E s p o l a R o a d Twin Peaks Road Mtn Road Northcrest Lane Titan Way Del Poniente Road Huntington Gate Drive Tierra Bonita Road Eden Grove Via Molinero Golden Sunset Lane Derringer Road Carlson Street Kalapana Street Jerome Drive Roberto Rio Road R i d g e v i e w P l a c e Crestview Court Durhullen Drive Rio Court Mesquite Tree Evergreen Lane El Topo Drive Los Nietos Avenue Segundo Court Carnitas StreetEl Dolora Way H i g h V a l l e y R o a d Saddlebrook Court Alando Place Espola Road Willow Ranch Road B2 B1-S B5-S B8 B6 B4 B3 B14 B11 B9 B10B7 B1-N B5-N B12 B13 Job No: BAH-01 Date: 01/24/12 µ I:\Gis\B\BAH-01Espola Rd\Map\EIR\Fig2-3-2_Noise_Barriers.mxd -EV 500 0 500250Feet Figure 2.3-2 ESPOLA ROAD IMPROVEMENT PROJECT Noise Receivers and Proposed Noise Barrier Locations LEGEND !1 Noise Receiver Location Proposed Noise BarrierB1 Section 2.3 – Noise Es p o l a R o a d I m p r o v e m e n t P r o j e c t F i n a l E I R 2.3-9 Ma y 2 0 1 3 Ta b l e 2 . 3 - 3 PR E D I C T E D F U T U R E N O IS E A N D B A R R I E R E F F E C T I V E N E S S A N A L Y S I S Segment Receiver AP N A d d r e s s Me a s u r e d Co n d i t i o n s No P r o j e c t Fu t u r e Ci t y o f Po w a y Cr i t e r i a No B a r r i e r s 3-Lane Future Pl a n n e d Ba r r i e r s 1 6' B a r r i e r 6 1 / 2 ' Ba r r i e r 7' B a r r i e r 7 1/2' Barrier8' Barrier 8 1/2' Barrier 9' Barrier Notes dB A d B A C h a n g e d B A C h a n g e I D d B A d B A d B A d B A dBA dBA dBA 1 53 3 2 1 2 4 3 0 1 0 0 1 4 2 1 1 T w i n P e a k s R o a d 6 2 . 4 6 2 . 9 0 . 5 6 0 6 3 . 4 1 . 0 – No PUA, Existing Barrier 2 8 3 2 1 3 0 3 2 9 0 0 1 4 1 4 9 R i o C o u r t 6 3 . 3 2 6 3 . 7 0 . 4 6 0 6 4 . 2 2 0. 9 B 1 - S 6 0 . 7 5 9 . 9 E x i s t i n g Barrier 9 3 2 1 3 0 3 2 7 0 0 1 4 1 5 4 R i o C o u r t 6 7 . 7 2 6 8 . 1 0 . 4 6 5 6 8 . 3 3 0. 6 B 1 - S 6 7 . 8 6 7 . 2 6 5 . 8 6 4 . 9 E x i s t i n g B a r r i e r 10 3 2 1 3 0 3 0 8 0 0 1 4 1 5 8 S e g u n d o C o u r t 6 7 . 9 6 8 . 3 0 . 4 6 5 6 8 . 6 0 . 7 B 1 - S 6 6 . 4 6 5 . 0 11 3 2 1 2 9 3 0 1 0 0 1 4 1 5 3 L o s N i e t o s A v e n u e 6 7 . 8 6 8 . 2 0 . 4 65 6 8 . 4 0 . 6 B 1 - N 6 8 . 4 6 8 . 4 6 7 . 0 6 6 . 7 6 5 . 9 6 5 . 4 6 4 . 4 12 3 2 1 2 9 1 3 2 0 0 1 4 7 3 5 A l o n d o P l a c e 6 7 . 3 6 7 . 7 0 . 4 65 6 8 . 0 0 . 7 B 2 6 6 . 7 6 6 . 3 6 5 . 8 6 4 . 7 13 3 2 1 2 9 1 3 0 0 0 1 4 7 5 1 A l o n d o P l a c e 6 8 . 1 6 8 . 6 0 . 5 6 5 68 . 7 0 . 6 B 2 6 8 . 7 6 8 . 3 6 7 . 1 6 6 . 6 6 6 . 3 6 4 . 9 14 3 2 1 0 2 0 4 1 0 0 1 4 8 0 2 E s p o l a R o a d 6 8 . 8 6 9 . 3 0 . 5 6 5 6 9 . 4 0 . 6 B 3 6 6 . 1 6 5 . 8 6 5 . 2 6 4 . 0 15 3 2 1 0 2 0 5 5 0 0 1 4 8 3 6 E s p o l a R o a d 6 6 . 1 6 6 . 6 0 . 5 6 5 6 7 . 0 0 . 9 – Shielded PUA 16 3 2 1 0 2 0 6 4 0 0 1 4 8 5 6 E s p o l a R o a d 6 6 . 6 6 7 . 0 0 . 4 6 5 6 7 . 4 0 . 8 – Shielded PUA 17 3 2 1 0 2 0 4 0 0 0 1 4 9 0 6 E s p o l a R o a d 6 7 . 9 6 8 . 3 0 . 4 6 5 6 8 . 5 0 . 6 – Shielded PUA 18 3 2 1 3 3 0 0 7 0 0 1 4 1 4 5 D u r h u l l e n D r i v e 6 7 . 8 6 8 . 2 0 . 4 6 5 6 8 . 4 0 . 6 B 4 6 2 . 9 43 3 2 1 2 1 0 3 3 0 0 1 4 9 3 7 E s p o l a R o a d 6 3 . 6 6 4 . 0 0 . 4 6 0 6 4 . 2 0 . 6 – Protected Outdoor Use Area Available 44 3 2 1 2 1 0 3 1 0 0 1 4 8 4 5 E s p o l a R o a d 6 5 . 3 6 5 . 7 0 . 4 6 5 6 6 . 0 0 . 7 B 1 4 6 4 . 9 45 3 2 1 2 1 0 4 5 0 0 1 4 8 3 9 E s p o l a R o a d 6 3 . 9 6 4 . 3 0 . 4 6 0 6 4 . 4 0 . 5 – Shielded PUA 46 3 2 1 2 1 0 3 6 0 0 1 4 8 3 1 E s p o l a R o a d 6 2 . 4 6 2 . 8 0 . 4 6 0 6 2 . 7 0 . 3 – Shielded PUA 47 3 2 1 2 1 0 5 0 0 0 1 4 8 1 5 E s p o l a R o a d 6 8 . 1 6 8 . 6 0 . 5 6 5 6 8 . 4 0 . 3 - S h i e l d e d P U A 48 3 2 1 2 4 1 0 1 0 0 1 4 7 2 9 E s p o l a R o a d 6 3 . 3 6 3 . 7 0 . 4 6 0 6 3 . 7 0 . 4 – Shielded PUA 49 3 2 1 2 4 1 0 2 0 0 1 4 7 1 1 E s p o l a R o a d 6 3 . 4 6 3 . 8 0 . 4 6 0 6 3 . 8 0 . 4 – Shielded PUA 50 3 2 1 2 4 1 0 4 0 0 1 4 6 7 9 E s p o l a R o a d 6 3 . 9 6 4 . 3 0 . 4 6 0 6 4 . 5 0 . 6 – Shielded PUA 51 3 2 1 2 4 1 0 6 0 0 1 4 6 4 3 E s p o l a R o a d 6 3 . 5 6 3 . 9 0 . 4 6 0 6 4 . 2 0 . 7 – Shielded PUA 52 3 2 1 2 4 1 0 8 0 0 1 4 6 1 1 E s p o l a R o a d 6 3 . 5 6 4 . 0 0 . 5 6 0 6 4 . 2 0 . 7 – ShieldedPUA 3 1 9 3 2 1 3 3 0 0 6 0 0 1 4 1 4 4 D u r h u l l e n D r i v e 6 6 . 7 6 7 . 1 0 . 4 6 5 6 6 . 8 0 . 1 B 5 - S 5 9 . 7 20 3 2 1 0 1 1 1 0 0 0 1 5 0 0 4 E s p o l a R o a d 6 7 . 0 6 7 . 4 0 . 4 6 5 6 7 . 2 0 . 2 B 5 - N 6 4 . 1 21 3 2 1 0 1 1 1 8 0 0 1 5 0 1 6 E s p o l a R o a d 6 8 . 1 6 8 . 5 0 . 4 6 5 6 8 . 1 0 . 0 - S h i e l d e d P U A 22 3 2 1 0 1 1 0 6 0 0 1 5 0 4 0 E s p o l a R o a d 6 6 . 4 6 6 . 8 0 . 4 6 5 6 6 . 7 0 . 3 – Shielded PUA 23 3 2 1 0 1 1 4 1 0 0 1 5 0 6 0 E s p o l a R o a d 6 5 . 7 6 6 . 2 0 . 5 6 5 6 6 . 4 0 . 7 – Shielded PUA 23 A 3 2 1 0 1 1 4 2 0 0 1 5 1 6 1 H u n t i n g t o n C o u r t 5 7 . 9 5 8 . 3 0 . 4 6 0 5 8 . 4 0 . 5 – Shielded PUA 37 3 2 1 0 1 1 1 4 0 0 1 5 1 3 1 E s p o l a R o a d 6 5 . 3 6 5 . 7 0 . 4 6 5 6 5 . 9 0 . 6 – Protected Outdoor Use Area Available 38 3 2 1 0 1 1 1 3 0 0 1 5 1 2 1 E s p o l a R o a d 6 7 . 3 6 7 . 8 0 . 5 6 5 6 7 . 6 0 . 3 B 1 1 6 1 . 9 39 3 2 1 0 1 1 2 4 0 0 1 5 1 0 9 E s p o l a R o a d 6 7 . 0 6 7 . 4 0 . 4 6 5 6 7 . 5 0 . 5 B 1 2 6 4 . 3 40 3 2 1 0 4 0 1 9 0 0 1 4 2 0 8 J e r o m e D r i v e 6 4 . 7 6 5 . 1 0 . 4 6 5 6 5 . 6 0 . 9 – Shielded PUA 41 3 2 1 0 4 0 1 8 0 0 1 4 2 1 1 J e r o m e D r i v e 6 6 . 2 6 6 . 6 0 . 4 6 5 6 7 . 1 0 . 9 – Shielded PUA 42 3 2 1 2 1 0 4 0 0 0 1 4 9 4 9 E s p o l a R o a d 6 6 . 9 6 7 . 3 0 . 4 6 5 6 7 . 8 0 . 9 B 1 3 5 7 . 5 Section 2.3 – Noise Es p o l a R o a d I m p r o v e m e n t P r o j e c t F i n a l E I R 2.3-10 Ma y 2 0 1 3 Ta b l e 2 . 3 - 3 ( c o n t . ) PR E D I C T E D F U T U R E N O IS E A N D B A R R I E R E F F E C T I V E N E S S A N A L Y S I S Segment Receiver AP N A d d r e s s Me a s u r e d Co n d i t i o n s No P r o j e c t Fu t u r e Ci t y o f Po w a y Cr i t e r i a No B a r r i e r s 3-Lane Future Pl a n n e d Ba r r i e r s 1 6' Ba r r i e r 6 1 / 2 ' Ba r r i e r 7' B a r r i e r 7 1/2' Barrier 8' Barrier 8 1/2' Barrier 9' Barrier Notes dB A d B A C h a n g e d B A C h a n g e I D d B A d B A d B A d B A dBA dBA dBA 4 24 3 2 1 0 1 2 4 8 0 0 1 5 2 4 4 E s p o l a R o a d 6 4 . 3 6 4 . 8 0 . 5 6 0 6 5 . 0 0 . 7 B 6 6 2 . 3 6 1 . 6 6 1 . 0 6 0 . 5 5 9 . 8 25 3 2 1 0 1 2 4 9 0 0 1 5 3 1 8 E s p o l a R o a d 6 2 . 8 6 3 . 3 0 . 5 6 0 6 3 . 5 0 . 7 B 7 6 0 . 7 6 0 . 4 6 0 . 1 5 9 . 6 5 8 . 8 26 3 2 1 0 1 2 5 0 0 0 1 5 3 6 0 E s p o l a R o a d 6 1 . 2 6 1 . 6 0 . 4 6 0 6 1 . 5 0 . 3 B 8 5 8 . 9 27 2 7 8 4 5 0 2 4 0 0 1 5 4 0 8 E s p o l a R o a d 6 3 . 5 6 3 . 9 0 . 4 6 0 6 3 . 8 0 . 3 B 9 5 8 . 9 28 2 7 8 4 5 0 1 0 0 0 1 4 1 3 5 W i l l o w R a n c h R o a d 5 8 . 8 5 9 . 2 0 . 4 6 0 5 4 . 9 - 3 . 9 – I n C o m p l i a n c e 29 2 7 8 4 5 0 1 1 0 0 1 5 4 5 7 M e s q u i t e T r e e T r a i l 5 9 . 8 6 0 . 2 0 . 4 6 0 6 0 . 4 0 . 6 – I n C o m p l i a n c e 30 2 7 8 4 5 0 1 3 0 0 1 5 4 7 7 M e s q u i t e T r e e T r a i l 5 9 . 7 6 0 . 2 0 . 5 6 0 6 0 . 3 0 . 6 – I n C o m p l i a n c e 31 2 7 8 4 5 0 1 5 0 0 1 5 4 9 7 M e s q u i t e T r e e T r a i l 5 9 . 4 5 9 . 8 0 . 4 6 0 5 9 . 7 0 . 3 – I n C o m p l i a n c e 32 2 7 8 4 6 2 3 9 0 0 1 5 4 9 0 H a r r o w L a n e 5 7 . 7 5 8 . 2 0 . 5 6 0 5 8 . 2 0 . 5 – I n C o m p l i a n c e 33 2 7 8 4 6 2 3 7 0 0 1 5 4 7 8 H a r r o w L a n e 5 8 . 2 5 8 . 6 0 . 4 6 0 5 8 . 6 0 . 4 – I n C o m p l i a n c e 34 2 7 8 4 6 2 3 5 0 0 1 5 4 6 4 H a r r o w L a n e 5 8 . 2 5 8 . 6 0 . 4 6 0 5 9 . 0 0 . 8 – I n C o m p l i a n c e 35 3 2 1 0 1 2 5 2 0 0 1 5 3 6 1 E s p o l a R o a d 6 3 . 8 6 4 . 2 0 . 4 6 0 6 4 . 6 0 . 8 B 1 0 6 2 . 8 6 2 . 2 6 1 . 5 6 0 . 7 5 9 . 9 36 3 2 1 0 1 1 1 5 0 0 1 5 1 5 9 E s p o l a R o a d 5 4 . 9 5 5 . 3 0 . 4 6 0 5 6 . 2 0 . 9 – I n C o m p l i a n c e I. L . = B a r r i e r N o i s e R e d u c t i o n ( I n s e r t i o n / L o s s ) N/ L = N o B a r r i e r N o i s e Re d u c t i o n ( N o / L o s s ) PU A = P r o t e c t e d U s e A r e a . S h i e l d e d p r o t e c t e d u s e a r e a s r e c e i v e sh i e l d i n g f r o m r o a d n o i s e t h r o u g h i n t e r v e n i n g s t r u c t u r e s a n d / o r t o p o g r a p h y . 1 T h e u l t i m a t e h e i g h t a n d l o c a t i o n o f n o i s e b a r r i e r s w i l l b e d e te r m i n e d d u r i n g f i n a l d e s i g n a n d a f t e r t h e f i n a l r e a s o n a b l e / f e a s i bl e a n a l y s i s i s c o m p l e t e d . 2 A s i x - f o o t w a l l c u r r e n t l y e x i s t s a t t h i s l o c a t i o n . D u e t o t h e p r o j e c t s o u n d w a l l h e i g h t it i s a n t i c i p a t e d t h e e x i s t i n g w a l l w ou l d b e r e m o v e d a n d a n e w w a l l , w i t h a p p r op r i a t e f o o t i n g s , w o u l d b e c o n s t r u c t e d . 3 T h i s r e c e i v e r h a s a n e x i s t i n g n o i s e - r e d u c i n g b a r r i e r w h o s e a t t e n u a t i o n i s f a c t o r e d i n t o t h e e x i s t i n g n o i s e l e v e l . Section 2.3 – Noise Espola Road Improvement Project Final EIR 2.3-11 May 2013 A church and commercial area are located south of Twin Peaks Road (Sites M1 and 53). Only construction activities primarily associated with an existing storm drain system are proposed south of Twin Peaks Road. There are no road widening improvements proposed for this area with associated Project changes in traffic proximity, and this area is not further addressed. No significant impacts would occur. The reader should note that because the Project is anticipated to receive partial federal funding, if the Project is approved by the City for construction, technical report requirements in accordance with NEPA also would be required in order for federal monies to be released. Noise modeling in accordance with standards current to FHWA and Caltrans would be completed at that time as part of a separate effort (see further discussion in Section 2.3.4, below). 2.3.4 Mitigation Measures Construction Period No mitigation is required for the less-than-significant short-term construction-period impacts. The City is recommending the following construction noise control measures, however, to further minimize noise effects at noise-sensitive locations during Project construction:  Each internal combustion engine, used for any purpose on the job or related to the job, shall be equipped with a muffler of a type recommended by the manufacturer. No internal combustion engine shall be operated on the Project without said muffler.  The noise level requirement shall apply to the equipment on the job or related to the job, including but not limited to trucks, transit mixer, or transient equipment that may or may not be owned by the contractor.  The use of loud signals shall be avoided in favor of light warnings except those required by safety laws for the protection of personnel.  Unnecessary idling of internal combustion engines within 100 feet of residences should be strictly prohibited.  Staging of construction equipment beyond 200 feet of residences and location of all stationary noise-generating construction equipment, such as air compressors and portable power generators, shall occur as far as practical from noise sensitive residences. The contractor will place all stationary construction equipment so that emitted noise is directed away from sensitive receptors (residences).  As directed by the City, the contractor will implement appropriate additional noise mitigation measures, including changing the location of stationary construction equipment, turning off idling equipment, rescheduling construction activity, notifying adjacent residents in advance of construction work, and installing acoustic barriers around stationary construction noise sources. Following Project Completion In accordance with the City General Plan Public Safety Element, noise reduction strategies were considered where Project impacts would expose existing residences to higher noise levels exceeding General Plan standards. City guidelines specify that noise abatement must be provided Section 2.3 – Noise Espola Road Improvement Project Final EIR 2.3-12 May 2013 to impacted residents where feasible. Factors that affect feasibility include topography, access requirements for driveways and ramps, presence of local cross streets, utility conflicts, other noise sources in the area, and safety considerations. The overall reasonableness of noise abatement is determined by considering factors such as predicted future increase in noise levels, expected noise abatement benefits, environmental impacts of abatement construction, opinions of affected residents, etc. Because of the configuration and location of the Project, abatement in the form of noise barriers is the only noise reduction strategy that is considered feasible, since Espola Road is already regulated to low speeds (45 miles per hour), and is immediately abutted by residential (and other) uses which would preclude the use of a buffer zone between the roadway and noise-sensitive receivers. Each of the walls proposed as mitigation meet initial feasibility and reasonableness criteria. As noted above, the City does not typically mitigate traffic noise at front yard areas as the focus is the outdoor space primarily used for recreational purposes by the resident (generally the backyard). The homes with front yards facing Espola Road also often have driveway entrances along Espola Road, which would limit the effectiveness of noise barriers placed along this segment of Espola Road. In addition, even if City standards would ordinarily mandate a higher wall to achieve recommended attenuation levels specified in the City Noise Element, City noise protection walls may be limited to a height of eight feet, if a taller wall is deemed to be aesthetically adverse. Preliminary information on the potential physical location and height of recommended noise barriers is provided in Table 2.3-3. Sound barriers of various heights are proposed based on which of the criteria the receiver falls within (currently under 60 dBA, between 60 and 65 dBA, or over 65 dBA), as described in Section 2.3.1. In general, sound walls of six to eight feet in height are proposed to address the current and increased noise along Espola Road. A few walls may exceed those heights, as indicated on Table 2.3-3. Figure 2.3-2 schematically indicates the proposed wall locations. Final design and placement of noise walls would require additional engineering input, including consideration of site-specific conditions and further noise modeling. Future modeling required as part of the NEPA compliance and funding effort for the Project, as well as input from property owners (who may not desire walls) also could result in changes to wall parameters.2 If pertinent engineering parameters change substantially during the final Project design, or if property owners reject proposed walls located on their private property, preliminary noise barrier designs may be modified (in height or extent) or eliminated from the final Project. If and when federal and final modeling is required and completed, a consistency analysis would be completed to confirm that sound barrier requirements do not vary substantially from those discussed above. If walls do vary substantially (e.g., changes in location, length or height), subsequent analysis may be required under CEQA. 2 Federal funding would not be provided for any sound wall where future noise levels would drop below 66 dBA. Differences between City and federal thresholds may result in varying wall height. Based on current federal modeling standards, it is considered likely that the proposed height of a number of walls could vary by one-half foot to two feet. Greater or lesser attenuation could be proposed due to federal requirements for attainment of minimum reduction levels prior to funding.