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HomeMy WebLinkAboutCT 15-06; THE WAVE; NOISE IMPACT STUDY; 2015-07-20City of Carlsbad The Wave Mixed Use Dev~Jopment Project '' '),J,\i''\ Noise Impact Study July 2015 ---------------------------- NOISE IMPACT STUDY THE WA VE MIXED USE DEVELOPMENT PROJECT Prepared by: City of Carlsbad 1635 Faraday A venue Carlsbad, CA 92008 (760) 602-4600 Prepared with the assistance of: Rincon Consultants, Inc. 5135 A venida Encinas, Suite A Carlsbad, California 92008 (760) 918-9444 July 2015 This report prepared on 50% recycled paper with 50% post-consumer content. The Wave Mixed Use Development Project Noise Impact Study Table of Contents Page Introduction ............................................................................................................................................. 1 Project Description .................................................................................................................................. 1 Setting ................................................................................................................................................... 1 Overview of Sound Measurement ................................................................................................. 1 Sensitive Receptors .......................................................................................................................... 3 Project Site Setting ............................................................................................................................ 3 Regulatory Setting ............................................................................................................................ 6 Vibration Standards ......................................................................................................................... 6 Impact Analysis ....................................................................................................................................... 7 Methodology and Significance Thresholds .................................................................................. 7 Temporary Construction Noise ...................................................................................................... 8 Construction Noise Reduction Measures ..................................................................................... 9 Temporary Construction-Related Vibration .............................................................................. 10 Long-Term Operational Noise Exposure .................................................................................... 11 References .............................................................................................................................................. 14 List of Figures Figure 1-Project Location .................................................................................................................... 2 Figure 2 -Noise Monitoring Locations ............................................................................................... 6 List of Tables Table 1 Noise Monitoring Results ........................................................................................................ 6 Table 2 Typical Construction Equipment Noise Levels .................................................................... 8 Table 3 Typical Maximum Construction Noise Levels at Various Distances from Project Construction ............................................................................................................................. 9 Table 4 Vibration Source Levels for Construction Equipment ....................................................... 10 Table 5 Existing and Project Related Noise Levels .......................................................................... 11 Appendices Appendix A Transportation Noise Model Files r City of Carlsbad The Wave Mixed Use Development Project Noise Impact Study r This pagf intentionally left blank. City of Carlsbad ii The Wave Mixed Use Development Project Noise Impact Study INTRODUCTION This report is an analysis of the potential noise impacts associated with The Wave, a mixed use development proposed for construction in the City of Carlsbad. The report has been prepared by Rincon Consultants, Inc. under contract to the applicant to support the environmental review process and address deficiencies in the application referenced in the June 15, 2015, Notice of Incomplete letter received from the City of Carlsbad. This study analyzes the potential for temporary impacts associated with construction activity and long-term impacts associated with operation of the proposed project. PROJECT DESCRIPTION The Wave is a residential/ commercial mixed use project proposed for development in Carlsbad, CA, on Assessor Parcel Number 203-101-20 (Figure 1). The project entails construction of a new 4-story mixed use commercial and multi-family building located on a 10,878 square foot lot at 2646 State Street (north of Beech Street and east of Carlsbad Village Station station) in downtown Carlsbad. The building would contain 21 residential and timeshare units (12 timeshare units, 1 apartment and 8 condominiums) in floors 2-4. The ground floor would contain 1,165 square feet of commercial, lobby and office space. A total of 36 parking spaces would be provided on-site at ground level (16 spaces) and in an underground parking garage (20 spaces). The project would require the demolition of an existing residential structure prior to construction. Decisions to approve entitlements associated with the proposed project are discretionary; thus, compliance with the California Environmental Quality Act (CEQA) will be required. This noise impact study will be used by the City of Carlsbad to support the discretionary review process. SETTING Overview of Sound Measurement Noise level (or volume) is generally measured in decibels (dB) using the A-weighted sound pressure level (dBA). The A-weighting scale is an adjustment to the actual sound pressure levels to be consistent with that of human hearing response, which is most sensitive to frequencies around 4,000 Hertz (about the highest note on a piano) and less sensitive to low frequencies (below 100 Hertz). Sound pressure level is measured on a logarithmic scale with the O dB level based on the lowest detectable sound pressure level that people can perceive (an audible sound that is not zero sound pressure level). Based on the logarithmic scale, a doubling of sound energy is equivalent to an increase of 3 dBA, and a sound that is 10 dBA less than the ambient sound level has no effect on ambient noise. Because of the nature of the human ear, a sound must be about 10 dBA greater than the reference sound to be judged as twice as loud. In general, a 3 dBA change in community noise levels is noticeable, while 1-2 dB changes generally are not perceived. Quiet suburban areas typically have noise levels in the range of 40-50 dBA, while arterial streets are in the 50-60+ dBA range. Normal conversational levels are in the 60-65 dBA range, and ambient noise levels greater than 65 dBA can interrupt conversations. Noise levels typically attenuate (or drop off) at a rate of 6 dBA per doubling of distance from point sources (i.e., industrial r City of Carlsbad The Wave Mixed Use Development Project Noise Impact Study .t "'•"""&OWt>P .... crm ,., ~ \J" ~~ ~ t-$ ~ l!'I • A'fff/Hrrt Spar.. Comf;I<. YI>' ... "" B \. i .. ,..,. .. \ ,. ~" @J 0 250 500 "'~ I Feet Imagery provided by Google and its licensOfs C> 2015. Ii I! Project Location cmJ ... -Ii .. I lluenO ~ <.. < " J !' ? 1 g U) li<J °' la n;,DI ~ ,.~ ~# ::;, \...r ~ ~~ ~ 'S! 1, t~ ~~ ,. ~, El "" ,. '9> \ ,.~ .. ~ B ,.. ~ B E)c..t.badv.-_s..1oo• " rf~ ..J.~?! 'If!>~ ~..,...,, C, N L A L4' Ocean side ~+ II Escondido Vicinity Map Figure 1 City of Carlsbad The Wave Mixed Use Development Project Noise Impact Study machinery). Noise from lightly traveled roads typically attenuates at a rate of about 4.5 dBA per doubling of distance. Noise from heavily traveled roads typically attenuates at about 3 dBA per doubling of distance. Noise levels may also be reduced by intervening structures; generally, a single row of buildings between the receptor and the noise source reduces the noise level by about 5 dBA, while a solid wall or berm reduces noise levels by 5 to 10 dBA. The manner in which older homes in California were constructed (approximately 30 years old or older) generally provides a reduction of exterior-to-interior noise levels of about 20 to 25 dBA with closed windows. The exterior-to-interior reduction of newer residential units and office buildings is generally 30 dBA or more (HMMH, 2006). In addition to the instantaneous measurement of sound levels, the duration of sound is important since sounds that occur over a long period of time are more likely to be an annoyance or cause direct physical damage or environmental stress. One of the most frequently used noise metrics that considers both duration and sound power level is the equivalent noise level (Leq). The Leq is defined as the single steady A-weighted level that is equivalent to the same amount of energy as that contained in the actual fluctuating levels over a period of time (essentially, the average noise level). Typically, Leq is summed over a one-hour period. Lmax is the highest RMS (root mean squared) sound pressure level within the measuring period, and Lmin is the lowest RMS sound pressure level within the measuring period. The time period in which noise occurs is also important since noise that occurs at night tends to be more disturbing than that which occurs during the day. Community noise is usually measured using the Day~Night Average Level (Ldn), which is the 24-hour average noise level with a 10-dBA penalty for noise occurring during nighttime (10 p.m. to 7 a.m.) hours, or the Community Noise Equivalent Level (CNEL), which is the 24-hour average noise level with a 5 dBA penalty for noise occurring from 7 p.m. to 10 p.m. and a 10 dBA penalty for noise occurring from 10 p.m. to 7 a.m. Noise levels described by Ldn and CNEL usually do not differ by more than 1 dBA. Sensitive Receptors Noise exposure goals for various types of land uses reflect the varying noise sensitivities associated with each of these uses. The City of Carlsbad General Plan Noise Element includes a variety of land use and development types that are noise sensitive including residences, schools, churches, hospitals and convalescent care facilities. Nearby sensitive receptors are single-family residences adjacent to the east and a mobile home park (Carlsbad Trailer Pla~to the north. Commercial are located to the west and south. Project Site Setting The most common and primary sources of noise in the project site vicinity are motor vehicles (e.g., automobiles, buses, trucks, and motorcycles) along State Street. Motor vehicle noise is of concern because it is characterized by a high number of individual events, which often create a sustained noise level, and because of its proximity to noise sensitive uses. Interstate 5 is located over 2,000 feet to the east. It is not audible as background noise and does not contribute to overall noise levels at the project site. Traffic on State Street is the primary noise source in the area; however, commercial uses (i.e., car wash and tire store) contribute to ambient noise levels. r City of Carlsbad 3 The Wave Mixed Use Development Project Noise Impact Study The Atchison, Topeka and Santa Fe Railroad (AT&SF) rail corridor is located two blocks (approximately 350 feet) to the west. This segment of the Los Angeles -San Diego -San Luis Obispo (LOSSAN) corridor is the second busiest passenger and freight rail corridor in the United States. According to the rail timetables, up to 50 trains (40 passenger and 10 freight trains) use the corridor segment daily between Oceanside and the Santa Fe Depot in downtown San Diego. Existing rail operations are audible at the project site, particularly the warning horns/bells that are used when trains are approaching the Carlsbad Village Drive crossing and station. Train operations affect ambient noise conditions within the area. McClellan-Palomar Airport is located approximately 4.5 miles southeast of the site. The site is outside the airport influence area; however, aircraft operations are audible as a distant source and contribute negligibly to existing noise levels. No other noise sources are near the project site. The City of Carlsbad General Plan Noise Element (1995) is currently being updated so the existing General Plan Noise Element is used for reference. The Noise Element provides noise contours associated with transportation corridors (i.e., roadways, railroad and airport). This provides a graphic illustration of sound levels near road corridors, but typically does not include effects of landforms and adjacent structures. Generally, barriers between a source and receiver absorb or reflect noise resulting in a quieter environment. Where barriers or landforms do not interrupt the noise transmission path from source to receiver, the contours prove to be reasonable estimates of the average noise level from roadway traffic. In areas where barriers or landforms interrupt sound transmission, the noise contours overestimate the extent to which a source intrudes into neighboring areas. The noise contour distances describe worst-case conditions because they do not account for any obstructions to the noise path, such as walls, berms, or buildings. As noted above, railroad noise is audible when train pass-by events occur. The contours provided in the General Plan Noise Element provide a reasonable prediction of rail noise levels at the site. Noise contours show the eastern project boundary is east of the 65 dBA/CNEL contour interval defined for the railroad track. To gather data on the general noise environment at the project site, two weekday morning 15- minute noise measurements were acquired in proximity to the project site on July 16, 2015, using an ANSI Type II integrating sound level meter. Site 1 is located in the southwest comer of the self-service car wash parking lot; Site 2 is located in the Community Interface Services parking lot. Both locations approximate existing noise conditions at the project site. The predominant noise source in the area during monitoring at Site 1 was traffic on State Street. However, construction activity occurring on the west side of State Street was audible as was sound from the adjacent self-service car wash facility located north of the site and tire store located to the west. The predominant noise source at Site 2 was parking lot operations and activities occurring at the adjacent mobile home park. Distant traffic on State Street to the west and Roosevelt Street to the east was audible but not the primary noise source. The temperature during monitoring was 70 degrees Fahrenheit with no measurable wind. During monitoring, a total of 50 cars/light trucks and two medium (six tires/two axles) passed the monitoring location. A total of 16 cars/light trucks and one medium delivery truck passed the monitoring location along State Street west of the site. One North County Transit District Coaster heavy rail stop occurred at Carlsbad Village Station during the first monitoring episode. An Amtrak pass by event occurred during the second monitoring episode. Table 1 identifies the noise measurement locations and measured noise levels. Monitoring locations are shown in Figure 2. The highest Leq was 59.6 dBA during the morning monitoring period. r City of Carlsbad 4 The Wave Mixed Use Development Project Noise Impact Study II I! Project Location • Monitoring Site 1 Monitoring Site 2 o 50 100 N ..__.........,,.., ........................ , J.. Feet f\ Imagery provided by Google and its t,cenaors C 2015 Noise Monitoring Locations Figure 2 City of Carlsbad The Wave Mixed Use Development Project Noise Impact Study Table 1 Noise Monitoring Results Measurement Location Primary Noise Source Southwest comer of the Carlsbad Self Service Car Wash parking lot approximately 50 feet east of State T raffle/Construction Street centerline. West side of Community Interface Services parking Commercial and lot between State Street to the west and Roosevelt mobile home park Street to the east. activity Source: Field visit using ANSI Type I/ Integrating sound level meter. Regulatory Setting Sample Time Leq (dBA) Weekday morning 57.9 Weekday morning 59.6 In 1976, the California Department of Health, State Office of Noise Control published a recommended noise/land use compatibility matrix which many jurisdictions have adopted as a standard in their general plan noise elements. This matrix indicates that residential land uses and other noise sensitive receptors preferentially should be located in areas where outdoor ambient noise levels do not exceed 65 to 70 dBA (CNEL or Ldn). Municipal Code and Noise Guideline Manual. The City of_ Carlsbad has established noise guidelines in the Noise Element of the City1s General Plan (City of Carlsbad, 1995) that are applicable for transportation noise sources. The noise guidelines identify compatible exterior noise levels for various land use types. Residential land uses are considered normally acceptable up to 60 dB CNEL. Commercial land uses are considered normally acceptable up to 65 dBA CNEL and conditionally acceptable up to 75 dBA. The City of Carlsbad Municipal Code regulates construction noise by limiting the hours of operation (City of Carlsbad 2003). Construction activities are allowed to occur Monday through Friday between the hours of 7 a.m. to sunset; and on Saturdays from 8 a.m. to sunset, excluding legal holidays. The City does not have quantitative noise level limits (i.e., based on sound levels) for general nuisance noise such as that associated with stationary equipment located on private property. For the purpose of this study, the residential standard of 60 dBA CNEL is used to evaluate potential exterior noise impacts associated with the proposed project. An interior noise standard of 45 dBA CNEL is used herein as referenced in the City of Carlsbad Noise Guidelines Manual (1995). Vibration Standards Vibration is a unique form of noise as the energy is transmitted through buildings, structures and the ground whereas audible noise energy is transmitted through the air. Thus, vibration is generally felt rather than heard. The ground motion caused by vibration is measured as particle velocity in inches per second and is referenced as vibration decibels (V dB). The vibration velocity level threshold of perception for humans is approximately 65 V dB. A vibration velocity r City of Carlsbad 6 ' l I l The Wave Mixed Use Development Project Noise Impact Study of 75 V dB is the approximate dividing line between barely perceptible and distinctly perceptible levels. City policies do not address construction-related vibration; thus, for the purpose of evaluating project-related vibration impacts, thresholds established in the Federal Transit Administration's (FTA) Transit Noise and Vibration Impact Assessment (May 2006) are used. A threshold of 65 VdB is used for buildings where low ambient vibration is essential for interior operations. These buildings include hospitals and recording studios. A threshold of 72 V dB is used for residences and buildings where people normally sleep (i.e., hotels and rest homes). A threshold of 75 VdB is used for institutional land uses where activities occur primarily during the daytime (i.e., churches and schools). The threshold used for the proposed project is 72 VdB as residences are the only sensitive receptors near the site. Construction activities such as blasting, pile driving, demolition, excavation or drilling have the potential to generate ground vibrations near structures. With respect to ground-borne vibration impacts on structures, the FTA states that ground-borne vibration levels in excess of 100 VdB would damage fragile buildings and levels in excess of 95 V dB would damage extremely fragile historic buildings. No historic buildings are known to occur near the site; thus, 100 V dB is used to quantify potential vibration impacts to neighboring structures. Construction activities referenced above that would generate significant vibration levels are not proposed. However, to provide information for use in completing the CEQA evaluation, construction-related vibration impacts are evaluated using the above referenced criteria. IMP ACT ANALYSIS Methodology and Significance Thresholds · Construction noise estimates are based upon noise levels reported by the Federal Transit Administration, Office of Planning and Environment, and the distance to nearby sensitive receptors. Reference noise levels from that document were used to estimate noise levels at nearby sensitive receptors based on a standard noise attenuation rate of 6 dB per doubling of distance (line-of-sight method of sound attenuation). Noise levels associated with existing and future traffic along area roadways were calculated using the Traffic Noise Model Version 2.5 Look-Up Tables (U.S. Department of Transportation, Federal Highway Administration [FHW A], April 2004) (noise modeling data sheets are provided in Appendix A). This study also estimates potential noise levels at the project site related to operation of the AT&SF rail line, which is located approximately 350 feet west of the site. A proprietary software program developed by Rincon Consultants, Inc. was used to perform noise calculations for rail operations. Specific assumptions used in the analysis are described below. A noise increase greater than 3 dBA is readily perceptible to the average human ear; and thus, is the level considered a substantial noise increase related to traffic operations. However, within the City of Carlsbad, noise impacts are also considered significant if noise levels would exceed 60 dBA CNEL. For the purpose of this evaluation, the peak hour Leq is used for traffic noise as r City of Carlsbad 7 The Wave Mixed Use Development Project Noise Impact Study it provides a more conservative estimate of potential noise levels. The CNEL is used within the rail noise discussion. All mechanical equipment associated with the project would be located in enclosed rooms on the roof top. Mechanical noise is not expected to be audible at adjacent receivers. Temporary Construction Noise The main sources of noise during construction activities would include heavy machinery used during demolition, grading, and clearing the site, as well as equipment used during building construction and paving. Table 2 demonstrates the typical noise levels associated with heavy construction equipment. As shown, average noise levels associated with the use of heavy equipment at construction sites can range from about 81 to 95 dBA at 25 feet from the source, depending upon the types of equipment in operation at any given time and phase of construction (Hanson, Towers, and Meister, May 2006). Table 2 Typical Construction Equipment Noise Levels Typical Level Typical Level {dBA) Typical Level (dBA) Equipment Onsite (dBA) 25 Feet 50 Feet from the 100 Feet from the from the Source Source Source Air Compressor 84 78 64 Backhoe 84 78 64 Bobcat Tractor 84 78 64 Concrete Mixer 85 79 73 Bulldozer 88 82 76 Jack Hammer 95 89 83 Pavement Roller 86 80 74 Street Sweeper 88 82 76 Man Lift 81 75 69 Dump Truck 82 76 70 Source: Noise levels based on FHWA Roadway Construction Noise Model (2006) Users Guide Table 1. Noise levels based on actual maximum measured noise levels at 50 feet (Lmax). Noise levels assume a noise attenuation rate of 6 dBA per doubling of distance. Noise-sensitive uses near the project site consist of single-family residences located adjacent to and east of the site and a mobile home park located north of the site. Construction noise will be audible at these properties. Table 3 shows typical maximum construction noise levels at various distances from construction activity, based on a standard noise attenuation rate of 6 dBA per doubling of distance. The noise level used to estimate the maximum noise level that could occur is based on use of a bulldozer as it is likely to be the noisiest type of equipment used over a sustained period of time adjacent to neighboring residences during demolition and site preparation activities. Actual noise levels will fluctuate throughout the day and may periodically exceed 84 dBA depending on the type and location of equipment used and whether multiple pieces of equipment are operating simultaneously in the same area. r City of Carlsbad 8 The Wave Mixed Use Development Project Noise Impact Study Table 3 Typical Maximum Construction Noise Levels at Various Distances from Project Construction Distance from Maximum Noise Level at Construction Receptor (dBA) 25 feet 88 50 feet 82 100 feet 76 250 feet 70 500 feet 64 1,000 feet 58 The sensitive receptors nearest to the proposed construction site are single-family residences located adjacent to the site along the northern and eastern property boundaries. At this distance, noise levels from construction could be as high as 88 dBA. However, temporary construction noise is not restricted if it occurs between the hours specific in the noise ordinance referenced herein. While not required, temporary construction noise can be reduced by implementing one or more of the following measures. Construction Noise Reduction Measures Temporary construction noise levels could be reduced through implementation of the following measures: r N-1 Construction Equipment. Use electrical power to run air compressors and similar power tools. Equip internal combustion engines with a muffler of a type recommended by the manufacturer and in good repair. Operate all diesel equipment with closed engine doors and should be equipped with factory-recommended mufflers. Shield construction equipment that continues to generate substantial noise at the project boundaries with temporary noise barriers, such as barriers that meet a sound transmission class (STC) rating of 25, sound absorptive panels, or sound blankets on individual pieces of construction equipment. Locate stationary noise-generating equipment, such as generators and compressors, as far as practically possible from the nearest residential property lines. N-2 Limit Operations Adjacent to Receivers. Lim.it the number of large pieces of equipment (i.e., bulldozers or concrete mixers) operating adjacent to receivers to one at any given time. N-3 Neighbor Notification. Provide notification to residential occupants adjacent to the project site at least 24 hours prior to initiation of City of Carlsbad 9 The Wave Mixed Use Development Project Noise Impact Study construction activities that could result in substantial noise levels at outdoor or indoor living areas. This notification should include the anticipated hours and duration of construction and a description of noise reduction measures being implemented at the project site. The notification should include a telephone number for local residents to call to submit complaints associated with construction noise. The notification should be posted on State Street (west) and Roosevelt Street (east) and should be easily viewed from adjacent public areas. Project construction would represent a temporary source of noise at the project site. Measures N-1 through N-3 would reduce construction noise levels. No significant residual impacts associated with construction noise are anticipated. Temporary Construction-Related Vibration Activities associated with residential developments do not generate vibration. Thus, this discussion will focus on temporary vibration caused by construction. Based on the information presented in Table 4, vibration levels could reach approximately 87 VdB at the residences adjacent to the site during construction assuming a bulldozer is the heaviest piece of equipment used during demolition. The nearest residences are located approximately 25 feet from the project site's northern and eastern boundary. As discussed below, 100 VdB is the threshold where minor damage can occur in fragile buildings. Vibration levels are projected to be under this threshold; thus, structural damage is not expected to occur as a result of construction activities associated with the proposed project. Vibration levels at residential units located east and north of the project site may exceed the groundborne velocity threshold level of 72 V dB for residences and/ or buildings where people sleep as discussed above. However, as long as construction occurs within the prescribed hours, the temporary impact would be considered adverse, but less than significant, since construction would not occur during nighttime hours when people normally sleep. Table 4 Vibration Source Levels for Construction Equipment Equipment Approximate VdB 25 Feet 50 Feet 60 Feet 75 Feet 100 Feet Large Bulldozer 87 81 79 77 75 Loaded Trucks 86 80 78 76 74 Jackhammer 79 73 71 69 67 Small Bulldozer 58 52 50 48 46 Source: Federal Railroad Administration, 1998 r City of Carlsbad 10 The Wave Mixed Use Development Project Noise Impact Study Long-Term Operational Noise Exposure Exterior Traffic Noise. Traffic is the primary noise source that would be generated by the proposed project. The proposed project would increase traffic volumes on State Street which may cause or contribute to an increase in traffic-related noise on and adjacent to the project site. Noise levels from traffic on State Street were estimated using the Traffic Noise Model Version 2.5 (U.S. Department of Transportation, Federal Highway Administration [FHWA], April 2004) (see Appendix A). Traffic noise was estimated for a weekday peak hour when the proposed project would add the largest volume of vehicles to the adjacent streets. Existing peak hour volumes were extrapolated based on the 15-minute traffic counts performed during noise monitoring. The peak hour is defined as the one-hour period between 7:00 am and 9:00 am and 4:00 pm and 6:00 pm when the highest volumes occur. Future traffic volumes were based on trip generation rates published by the Institute of Transportation Engineers (ITE) publication Trip Generation, s11i Edition for apartments. For the purpose of this analysis, the condominiums, apartment and timeshares were assumed to have the same trip generation rate or 0.62 evening (PM) peak hour trips per unit. This would equate to 13 trips (21 units multiplied by 0.62). The commercial area would generate 2.71 PM peak hour trips per 1,000 square feet or 3 trips. Thus, the proposed project would generate approximately 13 new residential trips plus 3 commercial trips for a total of 16 PM peak hour trips. However, the trip generation rate for the existing single-family residential use is 10 trips per day. The proposed project would replace this use; therefore, the total increase in trips associated with the project would be 6 during the peak hour. The trips were added to the baseline peak hour traffic on State Street to conservatively estimate noise levels associated with the project. The posted speed limit on State Street is 25 miles per hour (mph); however, 35 mph was the observed speed and the speed used in TNM. No stop controls are located in proximity to the site. Table 5 shows the existing and anticipated future (cumulative) noise levels at 30 feet from the State Street centerline. Existing mod~led roadway noise levels are 57.9 dBA adjacent to State Street which is the level measured in the field. To create a potentially significant and adverse impact, project-related traffic noise levels would have to cause a 3 dBA increase or cause noise levels to exceed 60 dBA. Table 5 Existing and Project Related Noise Levels Roadway Existing Existing Plus Project Project Change State Street adjacent to the project 57.9 dBA 58 +0.1 dBA site. Estimates of noise generated by traffic from roadway centerline at 30 feet for State Street. Refer to Appendix for full noise model output. Source: Federal Highway Administration Traffic Noise Model Version 2.5 Look-Up Tables. Significant Impact No As shown in Table 5, the expected exterior noise level increase associated with project traffic on State Street would be 0.1 dBA. As discussed, the net increase in trips associated with the proposed project would add 6 peak hour trips. The associated increase in noise levels would not be greater than 3 dBA nor would it exceed 60 dBA. Therefore, project impacts with respect to exterior traffic noise would be less than significant. r City of Carlsbad 11 The Wave Mixed Use Development Project Noise Impact Study Interior Traffic Noise. The proposed project would be designed to meet or exceed California Energy Code Title 24 standards, which specify construction methods and materials that result in energy efficient structures and up to a 30 dBA reduction in exterior noise levels (assuming windows are closed). When windows are open the insertion loss drops to about 10 dBA. Assuming that windows are closed, interior noise levels associated with traffic operations would be reduced from 58 dBA to 28 dBA, which would be below the 45 dBA standard. Exterior Railroad Noise. The AT&SF corridor is located approximately 350 feet to the west of the site and is used by Amtrak and the North County Transit District Coaster to provide passenger rail service. It is also used by freight trains during the late evening and nighttime hours. Based on the time tables, approximately 50 trains operate daily within this segment. Train volumes vary throughout the day, but are generally higher during the morning and evening commute hours and reflect the dominant use of this corridor by commuter rail and passenger trains. Train noise is generated by a combination of factors, including the number of locomotives, rail cars, speed, volume distribution over the day and nighttime hours and whether train horns are used. The existing rail noise levels at the project site were calculated using a proprietary software program developed by Rincon Consultants. Because Coaster trains stop at the Carlsbad station (Amtrak and freight trains do not), which is located approximately 2 blocks north of Carlsbad Village Drive, it was assumed the average speed through the area is 35 miles per hour. It was assumed that each passenger train has one locomotive and 10 rail cars. It was assumed that each freight train has have two locomotives and 50 cars. All trains are assumed to use the warning horn when approaching/ crossing Carlsbad Village Drive. Of the 50 train pass by events each day, five freight operations were assumed to occur during the nighttime (10:00 p.m. to 7:00 a.m.) hours. Based on these assumptions, the exterior CNEL at the project site (located 350 east of the rail corridor) is approximately 62.8 dBA when both passenger and freight rail operations are combined. This does not consider intervening buildings that may reduce noise levels by approximately 5 dBA 'for first floor/single story receivers. Thus, existing noise levels exceed the 60 dB CNEL recommended in the General Plan Noise Element for residential areas within the City of Carlsbad. The CNEL calculated for rail operations by this methodology is generally consistent with the 65 dBA contour line shown in the General Plan. Interior Railroad Noise. While the proposed project would have no impact on rail noise, the CNEL at the project site currently exceeds 60 dBA. Thus, project design features would be necessary to reduce interior noise levels to at least 45 dBA CNEL as specified in the City of Carlsbad Noise Guidelines Manual. As noted above, the proposed project would be designed to meet or exceed California Energy Code Title 24 standards which specify construction methods and materials that result in energy efficient structures and up to a 30 dBA reduction in exterior noise levels (assuming windows are closed). Assuming windows are closed, the CNEL associated with rail noise would be reduced from 62.8 dBA CNEL to 32.8 dBA CNEL, which would be consistent with City standards. No measures in addition to compliance with Title 24 design requirements would be necessary to reduce rail noise. Rail Vibration. The proposed project would be constructed approximately 350 feet east of the rail corridor. Thus, a screening evaluation of potential vibration impacts was performed to determine whether the project would be exposed to vibration levels that could be perceived by building residents. The proposed residential project would be considered a Category 2 land r City of Carlsbad 12 The Wave Mixed Use Development Project Noise Impact Study use for the purposes of vibration assessment as defined in the Federal Transit Administration, Transit Noise and Vibration Impact Assessment (2006). This category covers all residential land uses and any buildings where people sleep, such as hotels and hospitals. The impact criteria for a Category 2 land use is 75 V dB along corridors where train vibration events occur occasionally (i.e., 30 to 70 events daily). A vibration velocity of 75 VdB is the approximate dividing line between barely perceptible and distinctly perceptible levels. A screening level evaluation was performed to determine the likelihood of vibrations from the LOSSAN corridor affecting the proposed project. The screening distance for conventional commuter railroads was used to account for both passenger and freight trains. The distance between a conventional commuter railroad and Category 2 land use where the potential for a vibration impact to occur is 200 feet as defined in Table 9.2 within the FTA noise and vibration impact assessment methodology. The screening distances include a 5-decibel safety factor. The project site is located beyond the 200-foot screening distance; thus, vibration-related impacts are not anticipated and a more formal evaluation is not warranted. r City of Carlsbad 13 The Wave Mixed Use Development Project Noise Impact Study REFERENCES City of Carlsbad. General Plan Noise Element. 1993. City of Carlsbad. Noise Guidelines Manual. September, 1995. Federal Highway Administration. Roadway Construction Noise Model. 2006. Users Guide Table 1. Federal Highway Administration, Transportation Noise Model Version 2.5, 2004. Federal Transit Administration. Transit Noise and Vibration Impact Assessment. May 2006. Federal Rail Administration (FRA) Guidelines (Report Number 293630-1), December 1998. Hanson, Carl E., Towers, David A., and Meister, Lance D. (2006, May). Transit Noise and Vibration Impact Assessment. Federal Transit Administration, Office of Planning and Environment. http://www.fta.dot.gov/documents/FTA Noise and Vibration Manual.pd£ Harris Miller Miller & Hanson Inc. Transit Noise and Vibration Impact Assessment, Final Report. May 2006. Institute of Transportation Engineers (ITE) publication Trip Generation, 9th Edition r City of Carlsbad 14 • .. -~ RESULTS: SOUND LEVELS City of Carlsbad Rincon Consultants RESULTS: SOUND LEVELS PROJECT/CONTRACT: RUN: BARRIER DESIGN: <Project Name?> The Wave Mixed Use Project INPUT HEIGHTS <Project Name?> 20 July 2015 TNM2.5 Calculated with TNM 2.5 Average pavement type shall be used unless a State highway agency substantiates the use . --··--·--·-···----------____ of a differunt type with approval of FHWA, ~-~~~ I --ATMOSPHERICS: ..•.•.....• -·········--··-··-····-·-······-···· ····· ·····-······-···· ······ ·--··--········---··-·--··-·····----·-···-··--------·---Receiver ~-·-·-·-···--·-········· ············----······-·-·-····· ···········T---·--:----r············-:-::-,---· . ··-·----······----··-······--········-··---Name 1No. l#DUs !Existing 1No Barrier !With Barrier ' iLAeq1h !Uwq1;;---· -· 11 ........ ovaiaxlsting--rype iCalcu,.... ~N-o-is_e_R-ed_u_cti·-.o-n--~ ·--.. --.. -. -. -. ·-----.--..... -. -~· -+--~dBA-t:=-1:· tku~ £~ ~~~::~····--_[ J~-= ~!~~iver1 _______________________________ J ____ ~L ---~L------~~L .. ------~7-:~L___ a~ -~§ 1of --s1.9[ · o.of · · sj · ______ ::~:~ Dwe111nii"un1tit ···· · ·· · ···· ···· · ······ -··-·-----TtioUs-fNoise-Redu-ction-·-····--······· ········ I ----------~ --~~:---+~9-· --~W.9 :::-:~:::!---. ·. ··----···-·---······ -+ ··-·· ~/··· . ·· ~:~f ... · ·-~:o All that meet NR Goal ............ · j ·-·· 01--· O.or·····-O.or-· .. 0.0 C:\TNM25\Program\The Wave Existing 1 20July 2015 -,-~·~"' , trt''"' #' ---·ts'M--i~ttiirn•S. -""'oFT RESULTS: SOUND LEVELS City of Carlsbad Rincon Consultants RESULTS: SOUND LEVELS PROJECT/CONTRACT: RUN: BARRIER DESIGN: <Project Name?> The Wave Mixed Use Project INPUT HEIGHTS <Project Name?> 20July2015 TNM2.5 Calculated with TNM 2.5 Average pavement type shall be used unleaa a State highway agency substantiates the use ATMOSPHERICS: ---·---··----------68 deg F, 50% RH------·--·-···-···-----··--·--·-··------------of a_dlfferent type.wlth_.approval of FHWA.. ·----------·-·· Receiver Nuno r-r· 1= r~:::-!~_,~==1=~~~t°.""-1::.E:~:~~~~-;c: .... -·-·· -·-·------------·---··-···-· -U· --1,BA l,BA ---k. .j.. ----E'"""l i--J~ __ k_ __ J~~ .. . ~~er1 ___ ---------------~~i _____ ~T ....... _o.ol_ _______ sa.ot ___ saJ.. _______ sa.01 ~=-r ss.or-·--o:oi=----·-r=-··-.s:o Dwelling Units l# DUs :;:e ~~[AYW!' . -rM_-;_;._··--_--_-·' .. . ___ I dB ~ \dB ---- AJiSe~-_________ _ ___ ]_ ~.·.---•-~-. ···-.--. o.o.J __ o.o {:::!•~: NR Goal···--···-----··----------+--_ {L··----~:~t---------~:~t------~:~ C:\TNM25\Program\The Wave w-Project 1 20 July 2015 "'