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HomeMy WebLinkAboutCT 14-01; State Mixed Use 30; Tentative Map (CT)state and Oak Carlsbad Properties Project Noise Impact Study February 2014 State and Oak Carlsbad Properties Project Noise Impact Study Prepared for: State and Oak Carlsbad Properties, LTD 10946 Madrona Drive Sidney British Columbia V8L 5P2 Prepared by: Rincon Consultants, Inc. 5135 Avenida Encinas, Suite A Carlsbad, CA 92008 February 2014 This report is printed on 50% recycled paper. state and Oak Carlsbad Properties, LTD Noise Impact Study STATE AND OAK CARLSBAD PROPERTIES, LTD CARLSBAD, CALIFORNIA Noise Study Table of Contents Page Cover Letter Project Description 1 Setting 1 Overview of Sound Measurement 1 Sensitive Receptors 3 Project Site Setting 3 Regulatory Setting 5 Impact Analysis 7 Methodology and Significance Thresholds 7 Temporary Construction Noise 8 Construction Noise Reduction Measures 9 Residual Impacts 10 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 5 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 11 Table 5 Existing and Project Related Noise Levels 12 Appendices Appendix A Transportation Noise Model Look-Up Tables Files r state and Oak Carlsbad Properties, LTD state and Oak Carlsbad Properties, LTD Noise Impact Study This page intentionally left blank. r state and Oak Carlsbad Properties, LTD state and Oak Carlsbad Properties, LTD Noise Impact Study STATE AND OAK CARLSBAD PROPERTIES, LTD CARLSBAD, CALIFORNIA NOISE STUDY This report is an analysis of the potential noise impacts associated with the State and Oak Carlsbad Properties project, a mixed use development proposed for construction in the City of Carlsbad. The report has been prepared by Rincon Consultants, Inc. under contract to State and Oak Carlsbad Properties, LTD, to support the environmental review process. 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 project entails construction of a new 4-story mixed use commercial and multi-family building located at 3068 State Street (northeast corner of fhe State Street/ Oak Avenue intersection) in downtown Carlsbad, California (see Figure 1). The project site is comprised of three parcels: 203-297-06-00, 203-297-08-00 and 203-297-09-00 which total 18,006 square feet. Currently seven single story bungalow residences are present that would be demolished to accommodate the project. The proposed project would contain 33 residential units on floors 2-4. The ground floor would contain 3,608 square feet of commercial space, an 800 square foot timeshare activities space, a lobby area, and 40 garage parking spaces. Floors 2-4 would surround an interior courtyard containing an outdoor pool/recreation area constiucted on the second floor. Ingress/egress for vehicles would be along Oak Avenue. Decisions to approve entitlements associated with the proposed project are discretionary; thus, compliance with fhe Califorrua 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 0 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 r state and Oak Carlsbad Properties, LTD state & Oak Carlsbad Properties Carlsba VJ-. Imagery provided by ESRI and its licensors ©2013. ^ Project Location N A 0 1,000 lllll Feet Oceanside^ San Die Project Location Figure 1 Rincon Consultants state and Oak Carlsbad Properties, LTD Noise Impact Study 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 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 actual 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 envirorunental 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 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 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 dB. 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 north and east property boundary. All other land uses near the site are commercial. A public parking lot is located to the west. 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 and Oak Avenue. 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. State and Oak Carlsbad Properties, LTD r state and Oak Carlsbad Properties, LTD Noise Impact Study Interstate 5 is located approximately 2,000 feet to the east. It is audible as background noise and does contribute to overall noise levels at the project site. Carlsbad Village Drive, located approximately one block to the north and tiaffic along State Street and Oak Avenue also contributes to ambient noise levels. The Atichson, Topeka and Santa Fe Railroad (AT&SF) rail corridor is located one block (approximately 250 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 warrung horns that are used when approaching the Carlsbad Village Drive crossing and station. Train operations have a considerable effect on ambient noise conditions within the area. McClellan-Palomar Airport is located approximately 4 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; nonetheless, 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 tiansmission path from source to receiver, the contours prove to be reasonable estimates of the average noise level from roadway tiaffic. In areas where barriers or landforms interrupt the sound tiansmission, 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 obstiuctions to the noise path, such as walls, berms, or buildings. As noted, 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 just east of the 65 dBA contour interval defined for the railroad track. To gather data on the general noise environment at the project site, two weekday morning 20- minute noise measurements were acquired adjacent to the project site on December 3, 2013, using an ANSI Type II integrating sound level meter. The predominant noise source in the area during monitoring was tiaffic on State Stieet and Oak Avenue. However, tiaffic on Interstate 5 was audible as was construction activity occurring south of both monitoring sites. One helicopter overflight occurred during monitoring and multiple back up alarms from delivery vehicles in the area were audible. The temperature during monitoring was 58 degrees Fahrenheit, 68.3% relative humidity, and no measurable wind. During monitoring, a total of 28 cars/light tiucks passed the monitoring location on the southwest corner of the site along Oak Avenue. A total of 16 cars/light tiucks and one medium delivery tiuck passed the monitoring location along State Stieet west of the site. No tiain pass-by events occurred during monitoring; however, a tiain pass-by was measured in between the two monitoring events at the intersection of State Stieet and Oak Avenue. The Lmax (maximum noise level) was 88.9 dB; the Leq during the two minute monitoring event was 70.3 dB. State and Oak Carlsbad Properties, LTD r state and Oak Carlsbad Properties, LTD Noise Impact Study Table 1 identifies the noise measurement locations and measured noise levels. Monitoring locations are shown in Figure 2. As shown, the highest Leq was 57.6 dBA during fhe morning morutoring period. Table 1 Noise Monitoring Results IVIeasurement Location Primary Noise Source Sample Time Leq (dBA) South of the site across Oak Avenue near the intersection with State Street approximately 30 feet from the Oak Avenue centerline. Traffic/Construction Weekday morning 57.6 West of site across State Street approximately 30 feet from the State Street centerline. Traffic Weekday morning 55.9 Source; Field visit using ANSI Type II Integrating sound level meter. Regulatory Setting In 1976, the Califorrua Department of Health, State Office of Noise Contiol published a recommended noise/land use compatibility matiix which many jurisdictions have adopted as a standard in their general plan noise elements. This matiix 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 City's 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 dB CNEL and conditionally acceptable up to 75 dB. The City of Carlsbad Municipal Code regulates constiuction noise by limiting the hours of operation (City of Carlsbad 2003). Constiuction 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 dB 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). r state and Oak Carlsbad Properties, LTD state & Oak Cadsbad Properties • Project Location IVlonitoring Locations 0 1 130 N . . . 1 A Feet ^ Imagery provided by ESRI and its licensors ©2013. Project Monitoring Locations Figure 2 Rincon Consultants State and Oak Carlsbad Properties, LTD Noise Impact Study Vibration Standards Vibration is a unique form of noise as the energy is tiansmitted through buildings, stiuctures and the ground whereas audible noise energy is tiansmitted 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 (VdB). The vibration velocity level threshold of perception for humans is approximately 65 VdB. A vibration velocity of 75 VdB is the approximate dividing line between barely perceptible and distinctly perceptible levels. City policies do not address constiuction-related vibration; thus, for the purpose of evaluating project-related vibration impacts, thresholds established in the Federal Transit Administiation'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 VdB 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. Constiuction activities such as blasting, pile driving, demolition, excavation or drilling have the potential to generate ground vibrations near stiuctures. With respect to ground-borne vibration impacts on stiuctures, the FTA states that ground-borne vibration levels in excess of 100 VdB would damage fragile buildings and levels in excess of 95 VdB would damage extiemely fragile historic buildings. No historic buildings are known to occur near the site; thus, 100 VdB is used to quantify potential vibration impacts to neighboring stiuctures. Constiuction activities referenced above that would generate significant vibration levels are not proposed. However, to provide information for use in completing the CEQA evaluation, constiuction-related vibration impacts are evaluated using the above referenced criteria. IMPACT ANALYSIS Methodology and Significance Thresholds Constiuction noise estimates are based upon noise levels reported by the Federal Transit Administiation, Office of Planning and Environment, and the distancd 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 tiaffic along area roadways were calculated using the Traffic Noise Model Version 2.5 Look-Up Tables (U.S. Department of Transportation, Federal Highway Administiation [FHWA], 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 250 feet west of the site. A proprietary software State and Oak Carlsbad Properties, LTD r I state and Oak Carisbad Properties, LTD Noise Impact Study program developed by Rincon Consultants, Inc. was used to perform noise calculation associated with 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 tiaffic 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 tiaffic noise as 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 an enclosed room on the northeast corner of the building. Mechanical noise is not expected to be audible at adjacent receivers. Temporary Construction Noise The main sources of noise during constiuction activities would include heavy machinery used during demolition, grading, and clearing the site, as well as equipment used during building constiuction and paving. Table 2 demonstiates the typical noise levels associated with heavy constiuction equipment. As shown, average noise levels associated with the use of heavy equipment at constiuction 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 constiuction (Hanson, Towers, and Meister, May 2006). Table 2 Equipment Onsite Typical Level (dBA) 25 Feet from the Source Typical Level (dBA) 50 Feet from the Source Typical Level (dBA) 100 Feet from the 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 the northern and eastern site boundaries. Constiuction noise will be audible at these properties. Table 3 shows typical maximum constiuction noise levels at various distances from r State and Oak Carlsbad Properties, LTD State and Oak Carlsbad Properties, LTD Noise Impact Study constiuction 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. Table 3 Typical Maximum Construction Noise Levels at Various Distances from Project Construction Distance from Construction Maximum Noise Level at Receptor (dBA) 25 feet 88 50 feet 82 100 feet 76 250 feet 70 500 feet 64 1,000 feet 58 As noted, the sensitive receptors nearest to the proposed constiuction site are single-family residences located adjacent to the site along the northern and eastern property boundaries. At this distance, noise levels from constiuction could be as high as 88 dBA. However, temporary constiuction noise is not restiicted if it occurs between the hours specific in the noise ordinance referenced herein. While not required, temporary constiuction noise can be reduced by implementing one or more of the following measures. Construction Noise Reduction Measures Temporary consfruction noise levels could be reduced through implementation of the following measures: r N-l Construction Equipment. Electiical power shall be used to run air compressors and similar power tools. Internal combustion engines should be equipped with a muffler of a type recommended by the manufacturer and in good repair. All diesel equipment should be operated with closed engine doors and should be equipped with factory-recommended mufflers. Constiuction equipment that continues to generate substantial noise at the project boundaries should be shielded with temporary noise barriers, such as barriers that meet a sound fransmission class (STC) rating of 25, sound absorptive panels, or sound blankets on individual pieces of constiuction equipment. Stationary noise-generating equipment. State and Oak Carlsbad Properties, LTD state and Oak Carlsbad Properties, LTD Noise Impact Study such as generators and compressors, should be located as far as practically possible from the nearest residential properly lines. N-2 N-3 Limit Operations Adjacent to Receivers. Limit the number of large pieces of equipment (i.e., bulldozers or concrete mixers) operating adjacent to receivers to one at any given time. Neighbor Notification. Provide notification to residential occupants adjacent to the project site at least 24 hours prior to initiation of constiuction activities that could result in substantial noise levels at outdoor or indoor living areas. This notification should include the anticipated hours and duration of constiuction 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 constiuction noise. The notification should be posted on State Stieet (west). Oak Avenue (south) and Tyler Stieet (east) and should be easily viewed from adjacent public areas. Residual Impacts Project constiuction would represent a temporary source of noise at the project site. Measures N-l through N-3 would reduce constiuction noise levels. No residual impacts associated with constiuction 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 constiuction. Based on the information presented in Table 4, vibration levels could reach approximately 87 VdB at fhe residences adjacent to the site during constiuction assuming a bulldozer is the heaviest piece of equipment used during demolition. The nearest residences are located approximately 25 feet from the project'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, stiuctural damage is not expected to occur as a result of constiuction activities associated with the proposed project. Vibration levels at residential units located west of the project site would likely exceed the groundbome velocity threshold level of 72 VdB for residences and/or buildings where people sleep as discussed above. However, as long as constiuction occurs within the prescribed hours, the temporary impact would be considered adverse, but less than significant. r 10 State and Oak Carlsbad Properties, LTD state and Oak Carlsbad Properties, LTD Noise Impact Study Table 4 Vibration Source Levels for Construction Equipment Equipment Approximate VdB Equipment 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 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 tiaffic volumes on State Sfreet and Oak Avenue which may cause or contiibute to an increase in tiaffic-related noise on and adjacent to the project site. Noise levels from tiaffic on both State Stieet and Oak Avenue were estimated using the Traffic Noise Model Version 2.5 Look-Up Tables (U.S. Department of Transportation, Federal Highway Administiation [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 stieets. Existing peak hour volumes were extiapolated based on the 20-minute tiaffic 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 tiaffic volumes were based on tiip generation rates published by the Institute of Transportation Engineers (ITE) publication Trip Generation, 8"^ Edition for apartments which assumes 0.62 evening (PM) peak hour tiips per unit or 21 tiips (33 units multiplied by 0.62). The commercial area would generate 2.71 PM peak hour tiips per 1,000 square feet or 9 tiips. For the purpose of this evaluation, it was assumed the existing bungalows on-site have the same tiip generation as the proposed residential use. Thus, the proposed project would approximately 17 new residential tiips (21 new minus 4 existing) plus 9 commercial tiips for a total of 26 PM peak hour tiips. The tiips were added to the baseline peak hour tiaffic on both State Sfreet and Oak Avenue to conservatively estimate noise levels associated with the project. The posted speed limit on Oak Avenue and State Stieet is 25 miles per hour (mph). A stop sign is located on southbound State Stieet at the Oak Avenue intersection. Speeds were increased to 35 mph to account for acceleration noise associated with vehicles turning left onto Oak Avenue and right onto State Stieet. Table 5 shows the existing and anticipated future (cumulative) noise levels at 30 feet from the Oak Avenue and State Stieet centerline. Existing modeled roadway noise levels are 54 dBA adjacent to State Stieet and 54.8 dBA adjacent to Oak Avenue. Modeled noise levels are less than, but within 3 dBA of the measured noise levels which is acceptable given the type of background noise occurring during monitoring. To create a potentially significant and adverse impact, project-related tiaffic noise levels would have to cause a 3 dBA increase or cause noise levels to exceed 60 dBA. r 11 State and Oak Carlsbad Properties, LTD State and Oak Carlsbad Properties, LTD Noise Impact Study As shown in Table 5, the expected exterior noise level increase associated with project tiaffic on State Stieet would be 1.4 dBA. Traffic using Oak Stieet would increase the Leq by 1.1 dBA. This increase in roadway noise levels caused by the project would not be greater than 3 dBA nor would it exceed 60 dBA. Therefore, project impacts with respect to exterior tiaffic noise would be less than significant. Table 5 Roadway Existing Existing Plus Project Project Change Significant Impact State Street between Carlsbad Village Drive and Oak Avenue 54 dBA 55.4 +1.4 dBA No Oak Avenue between State Street and Tyler Street 54.8 dBA 55.9 dBA +1.1 dBA No Estimates of noise generated by traffic from roadway centerline at 30 feet for both State Street and Oak Avenue. Refer to Appendix for full noise model output. Source: Federal Highway Administration Traffic Noise Model Version 2.5 Look-Up Tables. Interior Traffic Noise. The proposed project would be designed to meet or exceed California Energy Code Titie 24 standards which specify constiuction methods and materials that result in energy efficient stiuctures 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 windows are closed, interior noise levels associated with tiaffic operations would be reduced from 56 dBA to 26 dBA which would be below the 45 dBA standard. Exterior Railroad Noise. The AT&SF corridor is located approximately 250 feet to the west of the site and is used by Amtiak and the North County Transit Distiict Coaster to provide passenger rail service. It is also used by freight frains during the late evening and nighttime hours. Based on the time tables, approximately 50 frains operate daily within this segment. Train volumes vary throughout the day but are generally higher during the morning and evening commute hours. Train noise is generated by a combination of factors including the number of locomotives, rail cars, speed, volume distiibution over the day and nighttime hours and whether tiain 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 frains stop at the Carlsbad station (Amtiak and freight frains 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 frain has one locomotive and 10 rail cars. For freight frains it was assumed they have two locomotives and 50 cars. All tiains are assumed to use the warning horn when approaching/crossing Carlsbad Village Drive. Of the 50 tiain pass by events each day, ten freight operations were assumed to occur during the evening and nighttime hours 7:00 p.m. and 7:00 a.m. Based on these assumptions, the exterior CNEL at the project site (located 250 east of the rail corridor) is approximately 66 dBA when both passenger and freight rail operations are combined. This does not consider the intervening buildings that may reduce noise levels by approximately 5 dBA for first floor/single story receivers. Even with the reduction, 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 r 12 State and Oak Carlsbad Properties, LTD state and Oak Carlsbad Properties, LTD Noise Impact Study operations by this methodology is consistent wifh the 65 dBA contour line shown in the General Plan. Interior Railroad Noise. While the proposed project will 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 Tifle 24 standards which specify constiuction methods and materials that result in energy efficient stiuctures 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 66 dBA CNEL to 36 dBA CNEL which would be consistent with the local standards. No measures in addition to compliance with Titie 24 design requirements would be necessary to reduce rail noise. Rail Vibration. As noted, the proposed project would be constiucted approximately 250 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. As a residential project, it would be considered a Category 2 land 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 VdB along corridors where frain vibration events occur occasionally (i.e., 30 to 70 events daily). As noted, vibration velocity of 75 VdB is the approximate dividing line between barely perceptible and distinctiy 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 frains. The distance between a conventional commuter railroad and Category 2 land use where fhe 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 proposed project site is located beyond the 200 foot screening distance; thus, vibration-related impacts are not anticipated and a more formal evaluation is not considered necessary. r state and Oak Carlsbad Properties, LTD 13 State and Oak Carlsbad Properties, LTD Noise Impact Study REFERENCES City of Carlsbad. General Plan Noise Element. 1993. City of Carlsbad. Noise Guidelines Manual. September, 1995. Federal Highway Administiation. Roadway Construction Noise Model. 2006. Users Guide Table 1. Federal Highway Adminisfration, Transportation Noise Model Look-Up Tables, 2004. Federal Transit Administiation. Transit Noise and Vibration Impact Assessment. May 2006. Federal Rail Administiation (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 Administiation, Office of Plarming and Environment. http://www.fta.dot.gov/documents/FTA Noise and Vibration Manual.pdf Harris Miller Miller & Hanson Inc. Transit Noise and Vibration Impact Assessment, Final Report. May 2006. Institute of Transportation Engineers (ITE) publication Trip Generation, 9"' Edition r state and Oak Carlsbad Properties, LTD 14 Appendix A Transportation Noise Model Look-Up Tables Files * * * * CASE INFORMATION * * * * * * * * Results calculated with TNM Version 2.5 * * * * * * * * TRAFFIC VOLUME/SPEED INFORMATION * * * * Automobile volume (v/h): 48.0 Average automobile speed (mph): 35.0 Medium truck volume (v/h): 3.0 Average medium truck speed (mph): 35.0 Heavy truck volume (v/h): 0.0 Average heavy truck speed (mph): 0.0 Bus volume (v/h): 0.0 Average bus speed (mph): 0.0 Motorcycle volume (v/h): 0.0 Average Motorcycle speed (mph): 0.0 * * * * TERRAIN SURFACE INFORMATION * * * * Terrain surface: hard * * * * RECEIVER INFORMATION * * * * DESCRIPTION OF RECEIVER # 1 Receiver 1 Distance from center of 12-ft wide, single lane roadway (ft): 32.8 A-weighted Hourly Equivalent Sound Level without Barrier (dBA): 54.0 file:///L|/...586%20Gnges,%20State%20&%20Oak%20Mxd%20Use%20Dev/Report/Draft'Appendix%20A/l_State%20Street%20Existin^ * * * * CASE INFORMATION * * * * * * * * Results calculated with TNM Version 2.5 * * * * * * * * TRAFFIC VOLUME/SPEED INFORMATION * * * * Automobile volume (v/h): 84.0 Average automobile speed (mph): 35.0 Medium truck volume (v/h): 0.0 Average medium truck speed (mph): 0.0 Heavy truck volume (v/h); 0.0 Average heavy truck speed (mph): 0.0 Bus volume (v/h): 0.0 Average bus speed (mph): 0.0 Motorcy c le vo lume (v/h): 0.0 Average Motorcycle speed (mph): 0.0 * * * * TERRAIN SURFACE INFORMATION * * * * Terrain surface: hard * * * * RECEIVER INFORMATION * * * * DESCRIPTION OF RECEIVER # 1 Receiver 1 Distance from center of 12-ft wide, single lane roadway (ft): 32.8 A-weighted Hourly Equivalent Sound Level without Barrier (dBA): 54.8 file.V//L|/...86%20Gnges,%20State%20&%20Oak%20Mxd%20Use%20Dev/Report/DrafVAppendix%20A/2_Oak%20Avenue%20Existing.txt[12W^ PM * * * * CASE INFORMATION * * * * * * * * Results calculated with TNM Version 2.5 * * * * * * * * TRAFFIC VOLUME/SPEED INFORMATION * * * * Automobile volume (v/h): 74.0 Average automobile speed (mph): 35.0 Medium truck volume (v/h): 3.0 Average medium truck speed (mph): 35.0 Heavy truck volume (v/h): 0.0 Average heavy truck speed (mph): 0.0 Bus volume (v/h): 0.0 Average bus speed (mph): 0.0 Motorcycle volume (v/h): 0.0 Average Motorcycle speed (mph): 0.0 * * * * TERRAIN SURFACE INFORMATION * * * * Terrain surface: hard * * * * RECEIVER INFORMATION * * * * DESCRIPTION OF RECEIVER # 1 Receiver 1 Distance from center of 12-ft wide, single lane roadway (ft): 32.8 A-weighted Hourly Equivalent Sound Level without Barrier (dBA): 55.4 file:///L|/...86%20Gnges,%20State%20&%20Oak%20Mxd%20Use%20Dev/Report/Draft/Appendix%20A/3_State%20Street%20w-Project.txt[12/6/2013 4:06:13 PM] * * * * CASE INFORMATION * * * * * * * * Results calculated with TNM Version 2.5 * * * * * * * * TRAFFIC VOLUME/SPEED INFORMATION * * * * Automobile volume (v/h): 110.0 Average automobile speed (mph): 35.0 Medium truck volume (v/h): 0.0 Average medium truck speed (mph): 0.0 Heavy truck volume (v/h): 0.0 Average heavy truck speed (mph): 0.0 Bus volume (v/h): 0.0 Average bus speed (mph): 0.0 Motorcycle volume (v/h): 0.0 Average Motorcycle speed (mph): 0.0 * * * * TERRAIN SURFACE INFORMATION * * * * Terrain surface: hard * * * * RECEIVER INFORMATION * * * * DESCRIPTION OF RECEIVER # 1 Receiver 1 Distance from center of 12-ft wide, single lane roadway (ft): 32.8 A-weighted Hourly Equivalent Sound Level without Barrier (dBA): 55.9 file:///L|/...6%20Gnges,%20State%20&%20Oak%20Mxd%20Use%20Dev/Report/Draft/Appendix%20A/4_Oak%20Avenue%20w-Project.txt[12/6/^ 4:06:15 PM]