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Home My WebLink AboutCT 2017-0008; HARDING & PALM TOWNHOUSE; NOISE AND VIBRATION IMPACT ANALYSIS; 2017-10-01NOISE AND VIBRATION IMPACT ANALYSIS HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA LSA October 2017 C NOISE AND VIBRATION IMPACT ANALYSIS HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA Submitted to: Robert Richardson Karnak Planning and Design 385 Christiansen Avenue Carlsbad, California 92008 Prepared by: LSA 703 Palomar Airport Road, Suite 260 Carlsbad, California 92011 (760) 931-5471 Project No. KPDl 702 LSA October 2017 NOISE AND VIBRATION IMPACT ANALYSIS OCTOBER 2017 HARDING AND PALM TOWNHOUSE. PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA TABLE OF CONTENTS LSA LIST OF ABBREVIATIONS AND ACRONYMS ............................................................................................ iii INTRODUCTION .......................................................................................................... 1 Project Description and Location .................................................................................................. 1 METHODOLOGY RELATED TO NOISE AND VIBRATION IMPACT ASSESSMENT ............... 4 CHARACTERISTICS OF SOUND ..................................................................................... 5 Measurement of Sound ................................................................................................................. 5 Physiological Effects of Noise ........................................................................................................ 7 Vibration ........................................................................................................................................ 8 REGULATORY SETTING .............................................................................................. 10 State of California Code of Regulations Title 24 .......................................................................... 10 City of Carlsbad General Plan ...................................................................................................... 10 City of Carlsbad City Ordinance ................................................................................................... 11 City of Carlsbad Noise Guidelines Manual .................................................................................. 11 Federal Transit Administration .................................................................................................... 12 OVERVIEW OF THE EXISTING ENVIRONMENT ............................................................ 14 Sensitive Land Uses in the Project Vicinity .................................................................................. 14 IMPACTS AND PROJECT DESIGN FEATURES ............................................................... 16 Short-Term Construction-Related Impacts ................................................................................. 16 Construction Noise Impacts ............................................................................................................. 16 Construction Vibration Building Damage Potential.. ........................................................................ 19 Long-Term Aircraft Noise Impacts ............................................................................................... 19 On-Site Land Use Compatibility Analysis ..................................................................................... 20 On-Site Traffic Impacts ..................................................................................................................... 20 On-Site Park Impacts ........................................................................................................................ 21 Long-Term Ground-Borne Noise and Vibration from Vehicular Traffic ...................................... 21 long-Term Off-Site Stationary Noise Impacts ............................................................................. 21 Summary of Recommendations .................................................................................................. 22 REFERENCES ............................................................................................................. 23 APPENDICES A: NOISE MEASUREMENT FIELD SHEETS AND DATA B: INTERIOR NOISE REDUCTION CALCULATION \\ptr11\projects\KPD1702\For DM\Noise Report_10202017.docx 110/23/17) C NOISE A.NO VIBRATION IMPACT ANALYSIS OCTOBER 2017 FIGURES HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA FIGURES AND TABLES LSA Figure 1: Project Location ....................................................................................................................... 2 Figure 2: Site Plan ................................................................................................................................... 3 Figure 3: Noise Monitoring Locations .................................................................................................. 15 TABLES Table A: Definitions of Acoustical Terms ................................................................................................ 7 Table B: Common Sound Levels and Their Noise Sources ...................................................................... 8 Table C: Allowable Noise Exposure1 ..................................................................................................... 10 Table D: Performance Standards for Nontransportation Sources (As Measured at Property Line of Source/Sensitive Land Use) ............................................................................................. 11 Table E: Ground-Borne Vibration and Noise Impact Criteria ............................................................... 13 Table F: Construction Vibration Damage Criteria ................................................................................. 13 Table G: Existing Noise Level Measurements ....................................................................................... 14 Table H: Typical Maximum Construction Equipment Noise Levels (Lmax) ............................................. 17 Table I: Vibration Source Amplitudes for Construction Equipment ..................................................... 19 \\ptrll\projects\KPD1702\For DM\Noise Report_10202017.docx (10/23/17) ii NOISE ANO VIBRATION IMPACT ANALYSIS Ocroern 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA Caltrans City CNEL dB dBA EPA FHWA ft FTA HVAC in/sec Ldn Leq I.max Lv Manual mi PA PPV RMS STC VdB V,et LIST OF ABBREVIATIONS AND ACRONYMS California Department of Transportation City of Carlsbad Community Noise Equivalent Level decibels A-weighted decibels United States Environmental Protection Agency Federal Highway Administration foot/feet Federal Transit Administration heating, ventilation, and air conditioning inches per second day-night average noise level equivalent continuous sound level maximum instantaneous noise level velocity in decibels City of Carlsbad Guidelines Manual miles Public address system peak particle velocity root-mean-square (velocity) Sound Transmission Class vibration velocity decibels reference velocity amplitude \\ptrll\projects\KPD1702\For DM\Noise Report_10202017.docx (10/23/17) LSA iii NOISE AND VIBRATION IMPACT ANALYSIS OCTOBER 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA INTRODUCTION LSA This noise and vibration impact analysis has been prepared to evaluate the potential impacts and project features associated with the proposed Harding and Palm Townhouse Project (project) in the City of Carlsbad (City), San Diego County, California. This report is intended to satisfy the City's requirement for a project-specific noise and vibration impact analysis and examines the impacts of the proposed noise-sensitive uses on the project site together with the project design features and standard conditions. Future noise level impacts are based on the noise measurement data gathered at the project site to properly account for the impacts associated with traffic on local roads immediately adjacent to the north and east, as well as traffic noise impacts from the 1-5 Freeway located farther northeast of the project site. It is also expected that the proposed project may experience elevated noise levels during sporting events at the baseball fields {Chase Park) on the opposite side of Palm Avenue to the northwest. PROJECT DESCRIPTION AND LOCATION Harding Palm, LLC (Project Applicant) proposes the construction of a 3-story townhouse development, located at 3535 Harding Street in the City. The project site is bordered by Palm Avenue to the northwest, Harding Avenue to the northeast, and existing single-family homes to the southeast and southwest. The project site is 0.44 acres. There is an existing single-family home on the project site. The project would develop six town home units in a total of three buildings, which would each have a private entertainment and recreation room as well as private two-car garages. Each unit would range in size from 2,100 to 2,900 square feet. The project location is illustrated on Figure 1, and the project conceptual plan is illustrated on Figure 2. \\ptrll\projects\KPD1702\For DM\Noise Report~l0202017.docx (10/23/17) 1 LSA LEGEND II U Project Location 1000 2000 FEET SOURCE: San Luis Rey (1975); Karnak Planning and Design (2017) l:\KPD 1702\G 15\Noise_projectlocation .mxd (10/17/2017) FIGURE 1 Harding & Palm Townhouse Project Project Location ''---., I ---.... I ' ~. . ·. I "' ~~· -, ·, • . ., . -'~·==·-'---~·--== = . .1 ~-c,,,,,J• .. ~~ l ·--~ __ .,;,.,,_--. '-, ,, ~ ( ) I ) \ •• 1 1lf )fV< ' ,v<,Jq l >!X X 'CY Y\/\, V-,,4,A,)<J ~ ' , ~'-L.-,-, · uv'-J _ . ....--t-···~ ,l<"x iq~/xV'\.>--<'.·YAX..X:ilX XX~~~¥~~;,,; ,--,--·-. i ! e'Tssq.tt. c:,;. ~.,,------(6-, '772 I 1 sq It ' , ' -6 ' : 'isq.~ /I :,:::J )' • '1 10·-1•J, ~>-----1 B --, , , , t B B -,,_ -.--.[ , , I 840sqft. I : , Gr -.. , UII 1 , 1 • --=-- B If;;~ --~Jsqll ! / ! I ,, -1 11 ··f=J (~ I 1 ' CS) IB -:, --== Gr : l I ~ \:!.I ' I I ! ~ K G<.~ : t:=:=:-' -1 -f':ci;;ri ..... I ! ! r:: -. .r=i~7, ..:_f _________ l _J '"·r--··' d F--r1~~-~-=--/ ,(VJ ' .~ <!JtaJ t,.,,u,.I, '~-® ;c.J 1~l c~~ ;---n , K ll t ~-W-o~( 7 , 1 . / i K r-1 ir ~&\.~1 ~-L K ~7r=-~ _11 L_ '__J JI _j~ J B I-FJI ··~ t:b:.trr•~-, -nC ~ L~~'L •;;J P) ['. 71,;, ' ~ ' ' , _ • . . "'7"7"'1' -. 42'-6" '-' f LLJ _ / 20'-11" ~ J -· _(lj_L-==··,--=<J~ I==--. '. I --"'~=""' r·//.'1 ,,t3•,-a• --t · -' -~-· I' • / / 6" t,,.) -----' J.:;:t:. -'. . -o y--. Garage I Ga • ·42' ! -11" • ~ ~:, Ir·-----:·--·-1 l1:--f~~ ----?JU ·-r---~..'.~~e _____ , I' r·--?~~~------"fa·la.'~~I Gar'dge n-------~ ,,J, _·· 1-<( 1 _ ___Js _ 1;1tt:~·-~ i 11 1 16, . -I: , : 1 1 - 1 -r·-----------I .. '/ / -1 ------~ , --,, I . t--,...i~[r--16 :t 1 , 16' r<s---'-'-...-. , . ' L I . . --,-, ,_ "'.--1-i --·-----L~---Ll ------------; -~ 19' : 1• . // . , -·--'-;"-· ---·---,-r"='~UIJ:. -,:c-j / -~->--I . ··. --.r' 1 \.,_ J ' -. N ,. '' · . , , . \· l r-V-L.L.,1. __ . -, _! 1---1· 1-L I ----------i __ \ : 00··----------------=--=~__Ji l . --; !~··JI I ~Is· ) ! . . ~ / . , / . . . . . . .. . : . . ,_·:, \ ~: I I . -• ~ '-1;1,...-:--I , . ----/ /,"" ~----.....__. Jf I 'i / ' 1 /~--r--...\. . y-~-~ ' ·--. -~'-=-'-. . ? . r----¥·-----k" •-· ; \· /-J ( LSA LEGEND U II Project Location I 0 12.5 25 FEET SOURCE: Bing Maps (2015); Karnak Planning and Design (2017) l:\KPD 1702\G IS\N oise _ SitePlan. mxd ( 10/17/2017) !,!.!i I -( l!al! '------r:-/--. ; • . --~-"' . ··.: ) \ }l~~~~--~f=Di~~-... ' ·•••·<ill"'" -......_ / '8~2-!Z. • • I ) --... -""<C"7 , , I ½ -1-1· 7 I ! . ( FIGURE 2 Harding & Palm Townhouse Project Site Plan NOISE ANO VIBRATION IMPACT ANALYSIS OCTOBER 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA LSA METHODOLOGY RELATED TO NOISE AND VIBRATION IMPACT ASSESSMENT Potential noise impacts are commonly divided into two groups: short-term construction and long- term operational (stationary source and mobile vehicular noise). Short-term impacts are usually associated with noise generated by construction activities. Long-term impacts include effects on surrounding land uses generated by a project once it is operational as well as those impacts that occur at a project site. The evaluation of noise and vibration impacts associated with the proposed project includes the following: • An analysis of short-term construction noise and vibration levels at off-site noise-sensitive uses, using the City's Noise Ordinance (City of Carlsbad 2013) and the construction vibration building damage and/or human annoyance criteria recommended by the Federal Transit Administration (FTA) and California Department ofTransportation (Caltrans). • An analysis of potential long-term noise impacts associated with off-site noise sources including both stationary and mobile sources, using noise monitoring results and reference noise levels compared to the City's pertinent noise standards. \\ptrll\projects\KPD1702\For DM\Noise Report_10202017.docx (10/23/17) 4 C NOISE AND VIBRATION IMPACT ANALYSIS OCTOBER 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA LSA CHARACTERISTICS OF SOUND Noise is usually defined as unwanted sound. Noise consists of any sound that may produce physiological or psychological damage and/or interfere with communication, work, rest, recreation, and sleep. To the human ear, sound has two significant characteristics: pitch and loudness. Pitch is generally an annoyance, while loudness can affect the ability to hear. Pitch is the number of complete vibrations, or cycles per second, of a wave resulting in the tone's range from high to low. Loudness is the strength of a sound that describes a noisy or quiet environment and is measured by the amplitude of the sound wave. Loudness is determined by the intensity of the sound waves combined with the reception characteristics of the human ear. Sound intensity refers to how hard the sound wave strikes an object, which in turn produces the sound's effect. This characteristic of sound can be precisely measured with instruments. The analysis of a project defines the noise environment of the project area in terms of sound intensity and its effect on adjacent sensitive land uses. MEASUREMENT OF SOUND Sound intensity is measured through the A-weighted scale to correct for the relative frequency response of the human ear. That is, an A-weighted noise level de-emphasizes low and very high frequencies of sound similar to the human ear's de-emphasis of these frequencies. Unlike linear units (e.g., inches or pounds), decibels are measured on a logarithmic scale representing points on a sharply rising curve. For example, 10 decibels (dB) is 10 times more intense than 1 dB, 20 dB is 100 times more intense than 1 dB, and 30 dB is 1,000 times more intense than 1 dB. Thirty decibels (30 dB) represents 1,000 times as much acoustic energy as 1 dB. The decibel scale increases as the square of the change, representing the sound pressure energy. A sound as soft as human breathing is about 10 times greater than 0 dB. The decibel system of measuring sound gives a rough connection between the physical intensity of sound and its perceived loudness to the human ear. A 10 dB increase in sound level is perceived by the human ear as only a doubling of the loudness of the sound. Ambient sounds generally range from 30 dB (very quiet) to 100 dB (very loud). Sound levels are generated from a source, and their decibel level decreases as the distance from that source increases. Sound dissipates exponentially with distance from the noise source. For a single-point source, sound levels decrease approximately 6 dB for each doubling of distance from the source. This drop-off rate is appropriate for noise generated by stationary equipment. If noise is produced by a line source (e.g., highway traffic or railroad operations) the sound decreases 3 dB for each doubling of distance in a hard site environment. Similarly, line sources with intervening absorptive vegetation or line sources which are located at a great distance to the receptor would decrease 4.5 dB for each doubling of distance. There are many ways to rate noise for various time periods, but an appropriate rating of ambient noise affecting humans also accounts for the annoying effects of sound. The equivalent continuous sound level (Leq) is the total sound energy of time-varying noise over a sample period. However, the \\ptrll\projects\KPD1702\For DM\Noise Report_10202017.docx (10/23/17) 5 NOISE AND VIBRATION IMPACT ANALYSIS OCTOBER 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA LSA predominant rating scales for human communities in the State of California are the Leq and Community Noise Equivalent Level (CNEL) or the day-night average noise level (Ldn) based on A-weighted decibels (dBA). CNEL is the time-varying noise over a 24-hour period, with a 5 dBA weighting factor applied to the hourly leq for noises occurring from 7:00 p.m. to 10:00 p.m. (defined as relaxation hours), and a 10 dBA weighting factor applied to noises occurring from 10:00 p.m. to 7:00 a.m. (defined as sleeping hours). Ldn is similar to the CNEL scale but without the adjustment for events occurring during the evening hours. CNEL and ldn are within 1 dBA of each other and are normally interchangeable. The City uses the CNEL noise scale for long-term noise impact assessment. Other noise rating scales of importance when assessing the annoyance factor include the maximum instantaneous noise level (Lmaxl, which is the highest exponential time-averaged sound level that occurs during a stated time period. The noise environments discussed in this analysis for short-term noise impacts are specified in terms of maximum levels denoted by lmax, which reflects peak operating conditions and addresses the annoying aspects of intermittent noise. It is often used together with another noise scale or noise standards in terms of percentile noise levels in noise ordinances for enforcement purposes. For example, the L10 noise level represents the noise level exceeded 10 percent of the time during a stated period. The L50 noise level represents the median noise level (i.e., half the time the noise level exceeds this level, and half the time it is less than this level). The l 90 noise level represents the noise level exceeded 90 percent of the time and is considered the background noise level during a monitoring period. For a relatively constant noise source, the leq and l 50 are approximately the same. The human perception of noise level increases can be described in three categories: • Inaudible/Not Perceptible: Changes in noise levels of less than 1 dB are inaudible to the human ear and often referred to as not perceptible. • Potentially Audible/Barely Perceptible: A potentially audible impact refers to a 1 dB to 3 dB change in noise levels. This range of noise levels has been found to be noticeable in low-noise environments. • Audible/Readily Perceptible: An audible impact refers to a noticeable increase in noise for humans. Audible increases in noise levels generally refer to a change of 3 dB or greater because this level has been found to be readily perceptible in exterior environments. For reference, a 10 dB increase is experienced by humans as a doubling of sound or perceived to be twice as loud. Only readily perceptible changes in existing ambient or background noise levels are considered potentially significant. \\ptrll\projeets\KPD1702\For DM\Noise Report_l0202017.docx (10/23/17) 6 C NOISE ANO VIBRATION IMPACT ANALYSIS OCTOBER 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA LSA PHYSIOLOGICAL EFFECTS OF NOISE Exposure to prolonged high noise levels has been found to have effects on human health (Suter 1991; World Health Organization 1999), including physiological and psychological effects to humans. Physical damage to human hearing begins at prolonged exposure to noise levels higher than 85 dBA. Exposure to high noise levels affects the entire system, with prolonged noise exposure in excess of 75 dBA increasing body tensions, thereby affecting blood pressure and functions of the heart and the nervous system. In comparison, extended periods of noise exposure above 90 dBA would result in permanent cell damage. When the noise level reaches 120 dBA, a tickling sensation occurs in the human ear, even with short-term exposure. This level of noise is called the threshold of feeling. As the sound reaches 140 dBA, the tickling sensation is replaced by the feeling of pain in the ear (the threshold of pain). A sound level of 160-165 dBA will result in dizziness or loss of equilibrium. The ambient or background noise problem is widespread and generally more concentrated in urban areas than in outlying, less developed areas. Table A lists definitions of acoustical terms, and Table B shows common sound levels and their sources. Table A: Definitions of Acoustical Terms Term Definitions Decibel, dB A unit of measurement that denotes the ratio between two quantities that are proportional to power; the number of decibels is 10 times the logarithm (to the base 10) of this ratio. Frequency, Hz Of a function periodic in time, the number of times that the quantity repeats itself in 1 second (i.e., number of cycles per second). A-Weighted Sound The sound level obtained by use of A-weighting. The A-weighting filter de-emphasizes the very low- Level, dBA and very high-frequency components of the sound in a manner similar to the frequency response of the human ear and correlates well with subjective reactions to noise. (All sound levels in this report are A-weighted, unless reported otherwise.) lo1, Lio, lso, l90 The fast A-weighted noise levels that are equaled or exceeded by a fluctuating sound level 1%, 10%, SO%, and 90% of a stated time period. Equivalent The level of a steady sound that, in a stated time period and at a stated location, has the same A- Continuous Noise weighted sound energy as the time-varying sound. level, lea Community Noise The 24-hour A-weighted average sound level from midnight to midnight, obtained after the Equivalent level, addition of 5 dBA to sound levels occurring in the evening from 7:00 PM to 10:00 PM and after the CNEL addition of 10 dBA to sound levels occurring in the night between 10:00 PM and 7:00 AM. Day/Night Noise The 24-hour A-weighted average sound level from midnight to midnight, obtained after the level, l.in addition of 10 dBA to sound levels occurring in the night between 10:00 PM and 7:00 AM. Lmax, Lmin The maximum and minimum A-weighted sound levels measured on a sound level meter, during a designated time interval, using fast time averaging. Ambient Noise level The all-encompassing noise associated with a given environment at a specified time; usually a composite of sound from many sources at many directions, near and far; no particular sound is dominant. Intrusive The noise that intrudes over and above the existing ambient noise at a given location. The relative intrusiveness of a sound depends upon its amplitude, duration, frequency, and time of occurrence and tonal or informational content, as well as the prevailing ambient noise level. Source: Handbook of Acoust,ca/ Measurements and Noise Control (Harns 1991). \ \ptrll \projects\KPD1702\For DM\Noise Report_10202017.docx (10/23/17) 7 NOISE AND VIBRATION IMPACT ANALYSIS ocroern 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA LSA Table B: Common Sound Levels and Their Noise Sources A-Weighted Sound Noise Subjective Noise Source Level in Decibels Environments Evaluations Near Jet Engine 140 Deafening 128 times as loud Civil Defense Siren 130 Threshold of Pain 64 times as loud Hard Rock Band 120 Threshold of Feeling 32 times as loud Accelerating Motorcycle at a Few Feet Away 110 Very Loud 16 times as loud Pile Driver; Noisy Urban Street/Heavy City Traffic 100 Very Loud 8 times as loud Ambulance Siren; Food Blender 95 Very Loud - Garbage Disposal 90 Very Loud 4 times as loud Freight Cars; Living Room Music 85 Loud - Pneumatic Drill; Vacuum Cleaner 80 Loud 2 times as loud Busy Restaurant 75 Moderately Loud - Near Freeway Auto Traffic 70 Moderately Loud - Average Office 60 Quiet One-half as loud Suburban Street 55 Quiet - Light Traffic; Soft Radio Music in Apartment 50 Quiet One-quarter as loud Large Transformer 45 Quiet - Avera~e Residence without Stereo Playing 40 Faint One-eighth as loud Soft Whisper 30 Faint - Rustling Leaves 20 Very Faint - Human Breathing 10 Very Faint Threshold of Hearing -0 Very Faint - Source: Compiled by LSA (2015). VIBRATION Vibration refers to ground-borne noise and perceptible motion. Ground-borne vibration is almost exclusively a concern inside buildings and is rarely perceived as a problem outdoors, where the motion may be indiscernible. Typically, there is more adverse reaction to effects associated with the shaking of a building. Vibration energy propagates from a source through intervening soil and rock layers to the foundations of nearby buildings. The vibration then propagates from the foundation throughout the remainder of the structure. Building vibration may be perceived by occupants as the motion of building surfaces, the rattling of items on shelves or hanging on walls, or a low-frequency rumbling noise. The rumbling noise is caused by the vibration of walls, floors, and ceilings that radiate sound waves. Annoyance from vibration often occurs when the vibration exceeds the threshold of perception by 10 dB or less. This is an order of magnitude below the damage threshold for normal buildings. Typical sources of ground-borne vibration are construction activities (e.g., blasting, pile driving, and operating heavy-duty earthmoving equipment), steel-wheeled trains, and occasional traffic on rough roads. Problems with both ground-borne vibration and noise from these sources are usually localized to areas within approximately 100 feet from the vibration source, although there are examples of ground-borne vibration causing interference out to distances greater than 200 ft (FTA 2006). When roadways are smooth, vibration from traffic, even heavy trucks, is rarely perceptible. It is assumed for most projects that the roadway surface will be smooth enough that ground-borne vibration from street traffic will not exceed the impact criteria; however, the construction of the project could result in ground-borne vibration that may be perceptible and annoying. \\ptrll\projects\KPD1702\For DM\Noise Report_10202017.docx (10/23/17) 8 C NOISE AND VIBRATION IMPACT ANALYSIS OCTOBER 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA LSA Ground-borne vibration has the potential to disturb people and damage buildings. Although it is very rare for typical construction activities to cause even cosmetic building damage, it is not uncommon for construction processes such as blasting and pile driving to cause vibration of sufficient amplitudes to damage nearby buildings (FTA 2006). Ground-borne vibration is usually measured in terms of vibration velocity, either the root-mean-square (RMS) velocity or peak particle velocity (PPV). The RMS is best for characterizing human response to building vibration, and PPV is used to characterize potential for damage. Decibel notation acts to compress the range of numbers required to describe vibration. Vibration velocity level in decibels is defined as: Lv = 20 log10 [V /Vref] where Lv is the vibration velocity in decibels (VdB), "V" is the RMS velocity amplitude, and "V,et" is the reference velocity amplitude, or 1 x 10-6 inches/second (in/sec) used in the United States. Factors that influence ground-borne vibration and noise include the following: • Vibration Source: Vehicle suspension, wheel types and condition, railroad track/roadway surface, railroad track support system, speed, transit structure, and depth of vibration source; • Vibration Path: Soil type, rock layers, soil layering, depth to water table, and frost depth; and • Vibration Receiver: Foundation type, building construction, and acoustical absorption. Among the factors listed above, there are significant differences in the vibration characteristics when the source is underground compared to when it is at the ground surface. In addition, soil conditions are known to have a strong influence on the levels of ground-borne vibration. Among the most important factors are the stiffness and internal damping of the soil and the depth to bedrock. Experience with ground-borne vibration indicates: (1) vibration propagation is more efficient in stiff clay soils than in loose sandy soils, and (2) shallow rock seems to concentrate the vibration energy close to the surface and can result in ground-borne vibration problems at large distances from a railroad track. Factors such as layering of the soil and the depth to the water table can have significant effects on the propagation of ground-borne vibration. Soft, loose, sandy soils tend to attenuate more vibration energy than hard rocky materials. Vibration propagation through groundwater is more efficient than through sandy soils. \\ptrll\projects\KPD1702\For DM\Noise Report_10202017.docx (10/23/17) 9 NOISE AND VIBRATION IMPACT ANALYSIS OCTOBER 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA LSA REGULATORY SETTING STATE OF CALIFORNIA CODE OF REGULATIONS TITLE 24 The California Code of Regulations, Title 24, Noise Insulation Standards, states that multifamily dwellings, hotels, and motels located where the CNEL exceeds 60 dBA must obtain an acoustical analysis showing that the proposed design would limit interior noise to less than 45 dBA CNEL. The maximum noise levels, either existing or future, must be used for this determination. Future noise levels must be predicted at least 10 years from the time of building permit application. CITY OF CARLSBAD GENERAL PLAN The noise standards within the Noise Element of the City's General Plan are aimed at protecting the citizens of Carlsbad from excessive noise levels that interfere with daily routine and comfort. Applicable issues and policies are summarized as follows: • Community Noise Exposure: The City allows for a normally acceptable noise level up to 65 dBA CNEL for multifamily uses and 60 dBA CNEL for single-family uses. • Allowable Noise Exposure: Table C indicates the acceptable limits of noise for various land uses for both exterior and interior environments from transportation sources. These limits are based on guidelines provided by the California Office of Planning and Research. Table C: Allowable Noise Exposure1 Outdoor Activity Areas"' (dBA Indoor Spaces Land Use CNEL) (dBACNEL) Residential 60q 45 Motels, Hotels 65 45 Hospitals, Residential Care Facilities, Schools, Libraries, 55 45 Museums, Churches, Day Care Facilities Playgrounds, Parks, Recreation Uses 65 so Commercial and Office Uses 65 so Industrial Uses 70 65 Source: City of Carlsbad General Plan Noise Element (September 2015). 1 Development proposed within the McClellan-Palomar Airport Area of Influence shall also be subject to the noise compatibility policies contained in the ALUCP. 2 The standard does not apply for nonresidential uses where an outdoor activity area is not proposed. Where the location of outdoor activity areas is unknown, the exterior noise level standard shall be applied to the property line of the receiving use. 3 .Where it is not possible to reduce noise in outdoor activity areas to the allowable maximum, levels up to 5 dB higher may be allowed provided that available exterior noise level reduction measures have been implemented and interior noise levels are in compliance with this table. 4 An exterior noise exposure level of 65 dBA CNEL is allowable for residential uses in a mixed-use project and for residential uses within the McClellan-Palomar Airport Area of Influence, pursuant to the noise compatibility policies contained in the ALUCP. ALUCP = Airport Land Use Consistency Plan CNEL = Community Noise Equivalent Level \\ptrll\projects\KPD1702\For DM\Noise Report_10202017.docx (10/23/17) dB= decibels dBA = A-weighted decibels 10 NOISE ANO VIBRATION IMPACT ANALYSIS OCTOBER 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CA~LSBAD, SAN DIEGO COUNTY, CALIFORNIA LSA Table D provides standards for noise from nontransportation noise sources, including, but not limited to, industrial facilities, automotive servicing, car washes, equipment yards, nightclubs, hotels, and shopping centers. These standards apply to the noise sources themselves, as measured at the edge of the property line; noise caused by motor vehicles traveling to and from the site is exempt from this standard. Table D: Performance Standards for Nontransportation Sources (As Measured at Property Line of Source/Sensitive Land Use) Daytime Nighttime Noise Level Descriptor (7:00 a.m. to 10:00 p.m.) (10:00 p.m. to 7:00 a.m.) Hourly lea, dB 55 45 Maximum Level, dB 75 65 Source: City of Carlsbad General Plan Noise Element (September 2015). Note: Each of the noise levels specified above shall be lowered by 5 dB for simple-tone noises, noises consisting of speech or music, or recurring impulsive noises. dB= decibels Leq = Equivalent continuous sound level CITY OF CARLSBAD CITY ORDINANCE Carlsbad City Ordinance 8.48.010 states that construction activities shall occur only between the hours of 7:00 a.m. to 6:00 p.m., Monday through Friday, and 8:00 a.m. to 6:00 p.m. on Saturday. No construction is allowed on Sunday or City-recognized holidays. CITY OF CARLSBAD NOISE GUIDELINES MANUAL The City of Carlsbad Noise Guidelines Manual (Manual) provides further information and direction associated with City noise policies. The Manual provides specific guidance for projects that would exceed the residential noise standards as follows: If the acoustical study shows that exterior or interior noise levels cannot be mitigated to the established standard as noted above (60 or 65 dB(A) CNEL or less for the exterior portion of residential projects, or 45 dB(A) CNEL or less for interior portions of residential units), the development shall not be approved without the following findings: a. The developer of the project has proved to the satisfaction of the Planning Commission or Design Review Board that it is not feasible to comply with the standard. b. The Planning Commission or Design Review Board must find that there are specifically identified overriding social and economic considerations which warrant approval of the development even though it does not meet the noise standard. c. All purchasers of the impacted property shall be notified in writing prior to purchase, and by deed disclosure in writing, that the property they are purchasing is \\ptrll\projects\KPD1702\For DM\Noise Report_l0202017.doCK (10/23/17) 11 NOISE AN,0 VIBRATION IMPACT ANALYSIS OCTOBER 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA noise impacted and does not meet Carlsbad noise standards for residential property. LSA In addition, appropriate mitigation and/or conditions of approval shall be incorporaled into the project in accordance with the Carlsbad Noise Guidelines Manual. Additionally, the Manual specifies that the use of natural barriers, such as earthen berms, is preferred and the construction of noise barriers is the least desirable form of mitigation. Lastly, it is specified within the Noise Barriers subsection that barriers should be constructed such that there are no cracks, gaps, or openings. FEDERAL TRANSIT ADMINISTRATION Vibration standards included in the FTA Transit Noise and Vibration Impact Assessment (FTA, May 2006) are used in this analysis for ground-borne vibration impacts on human annoyance, as shown in Table E. The criteria account for variation in project types as well as the frequency of events, which differ widely among projects. It is intuitive that when there will be fewer events per day, it should take higher vibration levels to evoke the same community response. This is accounted for in the criteria by distinguishing between projects with frequent and infrequent events, in which the term "frequent events" is defined as more than 70 events per day. The criteria for environmental impact from ground-borne vibration and noise are based on the maximum levels for a single event. Table F lists the potential vibration building damage criteria associated with construction activities, as suggested in the Transit Noise and Vibration Impact Assessment (FTA, May 2006). FTA guidelines show that a vibration level of up to 102 VdB (equivalent to 0.5 in/sec in PPV) (FTA, May 2006) is considered safe for buildings consisting of reinforced concrete, steel, or timber (no plaster), and would not result in any construction vibration damage. For a nonengineered timber and masonry building, the construction building vibration damage criterion is 94 VdB (0.2 in/second in PPV). \\ptrll\projects\KPD1702\For DM\Noise Report_10202017.docx (10/23/17) 12 NOISE AND VIBRATION IMPACT ANALYSIS OCTOBER 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA LSA Table E: Ground-Borne Vibration and Noise Impact Criteria Ground-Borne Vibration Impact Levels Ground-Borne Noise Impact Levels (VdB re 1 micro inch/sec) (dB re 20 micropascals) Land Use Category Frequent Occasional Infrequent Frequent Occasional Infrequent Events1 Events2 Events3 Events1 Events2 Events3 Category 1: Buildings 65 VdB4 65 VdB4 65 Vd84 N/A5 N/A5 N/A5 where vibration would interfere with interior operations Category 2: Residences 72VdB 75VdB 80VdB 35dBA 38 dBA 43dBA and buildings where people normally sleep Category 3: Institutional 75VdB 78VdB 83 VdB 40dBA 43 dBA 48dBA land uses with primarily daytime use Source: Federal Transit Administration, 2006 1 Frequent Events" is defined as more than 70 vibration events of the same source per day. Most rapid transit projects fall into this category. 2 "Occasional Events" is defined as between 30 and 70 vibration events of the same source per day. Most commuter trunk lines have this many operations. 3 Infrequent Events" is defined as fewer than 30 vibration events of the same kind per day. This category Includes most commuter rail branch lines. 4This criterion limit is based on levels that are acceptable for most moderately sensitive equipment, such as optical microscopes. Vibration-sensitive manufacturing or research will require detailed evaluation to define the acceptable vibration levels. Ensuring lower vibration levels in a building often requires special design of the HVAC systems and stiffened floors. 5 Vibration-sensitive equipment is generally not sensitive to ground-borne noise. dB= decibel(s) N/A = not applicable dBA = A-weighted decibel(s) RMS= root-mean-square HVAC = heating, ventilation, and air conditioning sec= second(s) inch/sec= inch(es) per second VdB = RMS vibration velocity level in decibels Table F: Construction Vibration Damage Criteria Building Category PPV (in/sec) Approximate Lv (VdB)1 Reinforced concrete, steel, or timber (no plaster) 0.50 Engineered concrete and masonry (no plaster) 0.30 Nonengineered timber and masonry 0.20 Buildings extremely susceptible to vibration damage 0.12 Source: Transit Noise and Vibration Impact Assessment (FTA 2006). 1 RMS VdB re 1 µin/sec. µin/sec= microinches per second FTA = Federal Transit Administration PPV = peak particle velocity in/sec= inches per second Lv = velocity in decibels \\ptrll\projects\KPD1702\For DM\Noise Report_10202017.docx (10/23/17) RMS= root-mean-square VdB = vibration velocity in decibels 102 98 94 90 13 NOISE AND VIBRATION IMPACT ANALYSIS OCTOBER 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA OVERVIEW OF THE EXISTING ENVIRONMENT LSA The primary existing noise source in the project area is traffic noise from nearby transportation facilities including: Palm Avenue, Harding Street, and the 1-5 Freeway. In addition, potential noise from the baseball fields at Chase Field northwest of project site may occur during practices and games. In order to assess the existing noise conditions in the area, noise measurements were conducted on the project site. Two long-term 48-hour measurements were taken from September 27th to 29th, 2017. Based on field observations, activities were not occurring at Chase Field located north of the site. Additionally, two short-term measurements were gathered on September 27th, 2017. The results of the measurements show that highest noise levels at the project site measured 67.9 dBA CNEL for existing conditions. The location of the noise measurements are shown in Figure 3 and the results are summarized in Table G. Measurement data and field survey sheets are provided in Appendix A. Table G: Existing Noise Level Measurements Daytime Noise Levels1 Location Description Day (dBAL..,) LT-1 Located near the western property line of the 1 54.8-58.l project site. 2 54.4-59.3 Located on the southeastern portion of the 1 58.2 -61.1 LT-2 project site approximately 55 feet west of Harding Street. 2 58.7 -62.1 ST-1 Located on the northern portion ofthe project 1 58.2 site, 25 feet from Palm Avenue. ST-2 Located on the southeastern portion of the 1 57.9 project site, 35 feet from Harding Street. Source: Compiled by L.SA (September 27-29, 2017). 1 Daytime Noise Levels= noise levels during the hours of 7:00 a.m. to 7:00 p.m. 2 Evening Noise Levels= noise levels during the hours of 7:00 p.m. to 10:00 p.m. 3 Nighttime Noise Levels = noise levels during the hours of 10:00 p.m. to 7:00 a.m. dBA = A-weighted decibels ft = feet L00 = equivalent continuous sound level SENSITIVE LAND USES IN THE PROJECT VICINITY Evening Noise Levels2 (dBA Le.) 58.2 -59.3 58.8-59.7 60.6-62.0 61.0-61.8 - - Nighttime Noise Daily Noise Levels3 Levels (dBAL..) (dBACNEL) 53.0 -63.4 65.1 55.7-63.9 66.1 55.6-65.0 67.0 57.6-65.0 67.9 -- -- The project site is surrounded by a park and residential uses. The closest sensitive receptors are: • Five single-family homes, which are located immediately to the southeast and southwest of the project site; and • Residential uses approximately 80 feet northeast of the project boundary, on the opposite side of Harding Street. Chase Field, located on the opposite side of Palm Avenue and is an active use park; however, it is not considered a noise sensitive land use for the purposes of this analysis. \\ptrll\projects\KPD1702\For DM\Noise Report_10202017.docx (10/23/17) 14 ' 0 15 FEET 30 U II Project Location ■ Long-Term Monitoring Location • Short-Term Monitoring Location SOURCE: Bing Maps 12015); Karnak Planning and Design 12017) l:\KPD1702\GIS\Noise_Monitoring.mxd (10/17/2017) FIGURE 3 Harding & Palm Townhouse Project Noise Monitoring Locations NOISE AND VIBRATION IMPACT ANALYSIS OCTOBER 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CAP.LSBAD, SAN DIEGO COUNTY, CALIFORNIA LSA IMPACTS AND PROJECT DESIGN FEATURES This section describes the short-and long-term noise and vibration impacts associated with the proposed project. SHORT-TERM CONSTRUCTION-RELATED IMPACTS The project would result in noise and vibration impacts during construction of the project as described below. Construction Noise Impacts Two types of short-term noise impacts would occur during project construction, including: (1) equipment delivery and construction worker commutes; and (2) project construction operations. The first type of short-term construction noise would result from transport of construction equipment and materials to the project site and construction worker commutes. These transportation activities would incrementally raise noise levels on access roads leading to the site. It is expected that larger trucks used in equipment delivery would generate higher noise impacts than trucks associated with worker commutes. The single-event noise from equipment trucks passing at a distance of 50 feet from a sensitive noise receptor would reach a maximum level of 84 dBA Lmax· However, the pieces of heavy equipment for grading and construction activities would be moved on site just one time and would remain on site for the duration of each construction phase. This one- time trip, when heavy construction equipment is moved on and off site, would not add to the daily traffic noise in the project vicinity. Additionally, the total number of daily vehicle trips would be minimal when compared to existing traffic volumes on the affected streets, and the long-term noise level change associated with these trips would not be perceptible. Therefore, equipment transport noise and construction-related worker commute impacts would be short term and would not result in a significant off-site noise impact. The second type of short-term noise impact is related to noise generated during excavation, grading, and building erection on the project site. There will be no pile driving as part of the construction of the project. Construction is completed in discrete steps, each of which has its own mix of equipment and, consequently, its own noise characteristics. These various sequential phases would change the character of the noise generated on the site and, therefore, the noise levels surrounding the site as construction progresses. Despite the variety in the type and size of construction equipment, similarities in the dominant noise sources and patterns of operation allow construction-related noise ranges to be categorized by work phase. Table H lists typical construction equipment noise levels recommended for noise impact assessments, based on a distance of 50 feet between the equipment and a noise receptor, taken from the Federal Highway Administration Roadway Construction Noise Model (RCNM; FHWA 2006). Typical noise levels range up to 90 dBA Lmax at 50 feet during the noisiest construction phases. The site preparation phase, which includes excavation and grading of the site, tends to generate the highest noise levels because earthmoving equipment is the noisiest construction equipment. \\ptrll\projects\KPDl 702\For DM\Noise Report_10202017.docx (10/23/17) 16 r ......, NOISE ANO VIBRATION IMPACT ANALVSIS OCTOBER 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA LSA Earthmoving equipment includes excavating machinery (e.g., backfillers, bulldozers, draglines, and front loaders). Earthmoving and compacting equipment includes compactors, scrapers, and graders. Typical operating cycles for these types of construction equipment may involve 1 or 2 minutes of full-power operation followed by 3 or 4 minutes at lower power settings. Table H: Typical Maximum Construction Equipment Noise Levels (Lmax) Acoustical Suggested Maximum Sound Levels for Type of Equipment Usage Factor Analysis (dBA L.nax at SO feet) Air Compressor 40 80 Backhoe 40 80 Cement Mixer so 80 Concrete/Industrial Saw 20 90 Crane 16 85 Excavator 40 85 Forklift 40 85 Generator so 82 Grader 40 85 Loader 40 80 Pile Driver 20 101 Paver so 85 Roller 20 85 Rubber-Tired Dozer 40 85 Scraper 40 85 Tractor 40 84 Truck 40 84 Welder 40 73 Source: Federal Highway Administration, Highway Construction Noise Handbook (2006). dBA = A-weighted decibel(s) lmax = maximum instantaneous noise level In addition to the referenced maximum noise level, the usage factor provided in Table H is utilized to calculate the hourly noise level impact for each piece of equipment based on the following equation: where: L,q(equip) = E.L. + lOlog(U F.)-20log(!) Leq (equip) = Leq at a receiver resulting from the operation of a single piece of equipment over a specified time period E.L. = noise emission level of the particular piece of equipment at a reference distance of 50 feet U.F. = usage factor that accounts for the fraction of time that the equipment is in use over the specified period oftime D = distance from the receiver to the piece of equipment \\ptrll\projects\KPDl 702\For DM\Noise Report_10202017.docx (10/23/17) 17 NOISE AND VIBRATION IMPACT ANALYSIS OCTOBER 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA LSA Each piece of construction equipment operates as an individual point source. Using the following equation, a composite noise level can be calculated when multiple sources of noise operate simultaneously: Leq (composite) ~ 10 • log10 ( t 10\~) The composite noise level of the two loudest pieces of equipment, the bulldozer and scraper, during the earthmoving phase of construction, as required by the FTA criteria, would be 88 dBA Leq at a distance of 50 feet from the construction area. Once composite noise levels are calculated, reference noise levels can then be adjusted for distance using the following equation: Leq (at distance X) = Leq (at 50 feet) -20 * lo g10 (:0) In general, this equation shows that doubling the distance would decrease noise levels by 6 dBA while halving the distance would increase noise levels by 6 dBA. When construction occurs at the perimeter of the project site, noise level impacts at the single-family home to the southwest 10 feet from the property line may approach 102 dBA Leq while noise level impacts at the single-family homes to the southeast 40 feet from the property line may approach 90 dBA Leq. Although the project construction noise would be higher than the ambient noise in the project vicinity, it would cease to occur once the project construction is completed. Also, construction is restricted to daytime hours such that interference with sleep would be minimal. The following construction noise reduction measures would comply with the City's Noise Ordinance and reduce construction noise impacts to the extent feasible as suggested by the Manual: • Construction activities occurring as part of the project shall be subject to the limitations and requirements of the City of Carlsbad Noise Ordinance, which states that construction activities shall occur only between the hours of 7:00 a.m. to 6:00 p.m., Monday through Friday, and 8:00 a.m. to 6:00 p.m. on Saturday. • Prior to project approval, the project proponent shall produce evidence acceptable to the City that: o All construction vehicles or equipment, fixed or mobile, operated within 1,000 feet of a dwelling or noise sensitive use shall be equipped with properly operating and maintained mufflers. o Stockpiling and/or vehicle staging areas shall be located as far as practicable from dwellings and other noise sensitive receptors. \\ptrll\projects\KPD1702\For DM\Noise Report_10202017.docx (10/23/17) 18 C NOISE AND VIBRATION IMPACT ANALYSIS OCTOBER 2017 Construction Vibration Building Damage Potential HARO/NG AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA LSA Ground-borne noise and vibration from construction activity would be mostly low to moderate. Bulldozers and other heavy-tracked construction equipment generate 87 VdB (or 0.089 in/sec PPV) of ground-borne vibration when measured at 25 feet, based on the Transit Noise and Vibration Impact Assessment (FTA, May 2006). This range of ground-borne vibration levels would dissipate with distance from the project site and would not result in any human annoyance at the nearest single-family residences, which are 25 feet from the project construction activity. As shown in Table F, it would take a minimum of 90 VdB (or 0.12 in/sec PPV) to cause any potential building damage. FTA guidelines show that a vibration level of up to 102 VdB (equivalent to 0.5 in/sec in PPV) (FTA 2006) is considered safe for buildings consisting of reinforced concrete, steel, or timber (no plaster), and would not result in any construction vibration damage. For a nonengineered timber and masonry building, the construction vibration damage criterion is 94 VdB (or 0.2 in/sec in PPV). Table I further shows the PPV values at 25 feet from the construction vibration sources and vibration levels (in terms of VdB) at 25 feet from construction vibration sources. Table I: Vibration Source Amplitudes for Construction Equipment Reference PPV/Lv at 25 feet Equipment PPV (In/sec) Ly (VdB)1 Vibratory Roller 0.210 94 Hoe Ram 0.089 87 Large Bulldozer 0.089 87 Caisson Drilling 0.089 87 Loaded Trucks 0.076 86 Jackhammer 0.035 79 Small Bulldozer 0.003 58 Sources: Transit Noise and Vibration Impact Assessment (FTA 2006). 1 RMS VdB re 1 µin/sec. µin/sec= microinches per second FTA = Federal Transit Administration in/sec= inches per second Lv = velocity in decibels PPV = peak particle velocity RMS= root-mean-square VdB = vibration velocity in decibels As shown in Table I, operation of the vibratory roller would generate ground-borne vibration levels that would exceed the FTA vibration-induced architectural damage threshold of 0.2 PPV. Therefore, vibration-induced architectural damage impacts from on-site construction activities could potentially be significant without mitigation. However, by eliminating the use of vibratory rollers, impacts from vibration would be less than significant. LONG-TERM AIRCRAFT NOISE IMPACTS The project is approximately 4 miles (mi) northwest of McClellan Palomar Airport and 4.2 mi south of Oceanside Municipal Airport. The proposed project is located well outside the 65 dBA CNEL noise contours of these airports; therefore, noise-related impacts due to airport activities would be less than significant and no mitigation is required. \\ptrll\projects\KPD1702\For DM\Noise Report_10202017.doc• (10/23/17) 19 NOISE AND VIBRATION IMPACT ANALYSIS OCTOBER 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SA.N DIEGO COUNTY, CALIFORNIA LSA ON-SITE LAND USE COMPATIBILITY ANALYSIS The proposed project is considered an infill project and is located in an area in which all surrounding parcels are currently in use. For this reason, this analysis relies on the existing measured noise levels to provide the most accurate description of the noise environment. Based on monitoring results shown in Table G, noise levels at the project site are 67.9 dBA CNEL. On-Site Traffic Impacts As presented on the Caltrans Data Branch website, the Average Daily Traffic (ADT) for the adjacent segment of 1-5 in 2015 was 195,000 vehicles per day. Based on information presented in the Transportation Concept Report for Interstate 5 (Caltrans 2017), the ADT grown percentage per year for this segment of freeway is 0.61 percent. Utilizing this growth factor, the current Year 2017 ADT would be approximately 197,400 vehicles per day and the Year 2040 ADT would be approximately 227,000 vehicles per day. The following equation where Vexisting equal the existing daily volume, Viuture equals the future daily volumes, CNELexistins equals the existing noise level, and CNEL-1uture equals the future noise level, was used to calculate future on-site noise levels: CNELruture = CNELexisting + 10 log10 [V1uture/Vexisting] Takin~ into account the future volume adjustment of 0.6 dBA CNEL, future noise levels are expected to be 68.5 dBA CNEL. While this noise level exceeds the City's allowable noise exposure level of 60 dBA CNEL, the private recreation space for each unit is the first floor patio which is a point of access from the sidewalk along Palm Avenue. Given the necessity to access the unit through the front patio, a solid barrier with no breaks or gaps is not a feasible form of noise reduction therefore the proposed project shall be required to disclose to all future tenants or owners that exterior noise levels exceed the City's exterior noise level standard. Though exterior levels exceed the City's standard, the project must demonstrate compliance with the interior noise standard of 45 dBA CNEL. Based on the EPA's Protective Noise Levels (EPA 1978), with windows and doors open, interior noise levels would be 57.0 dBA (i.e., 68.5 dBA-12 dBA = 56.5 dBA), which would exceed the 45 dBA CNEL interior noise standard. Using the architectural plans for the proposed project {Karnak Planning and Design 2017), LSA conducted interior noise calculations for the bedroom of Unit 6 on the second floor, which is on the east side of the building closest to the 1-5 Freeway; and has multiple windows and a sliding glass door with typical stucco construction. The results of the analysis show a 24.3 dBA exterior-to- interior noise reduction. These calculations (shown in Appendix B) assume a wall rating of Sound Transmission Class (STC) 46 (Harris 1997) along with a sliding glass door rating of STC-29 and a window rating of STC-25 (Milgard 2008). With windows closed, interior noise levels at the master bedroom would be 44.2 dBA (i.e., 68.S dBA-24.3 dBA = 44.2 dBA), which is below the 45 dBA CNEL interior noise standard with windows closed for noise-sensitive land uses. Therefore, with standard building construction, central air conditioning that would allow windows to remain closed, and windows with a minimum STC rating of 25 or higher and sliding glass doors with a minimum STC rating of 29 or higher, the interior noise levels would be considered acceptable. \\ptrll\projects\KPD1702\For DM\Noise Report_10202017.docx (10/23/17) 20 NOISE AND VIBRATION IMPACT ANALVSIS OCTOBER 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA LSA On-Site Park Impacts The proposed project would potentially be exposed to noise impacts associated with spectators cheering during baseball games at Chase Field north of the project site. Noise dissipates with distance as it loses energy. The farther the noise receiver is from the noise source, the lower the perceived noise level. Geometric spreading causes the sound level to attenuate, resulting in a noise level reduction of 6 dBA for each doubling of distance from a point source, similar to spectators in the existing bleachers, to the noise-sensitive receptor of concern. Based on reference noise level measurements gathered by LSA at another park site during a sporting event, noise levels from spectators cheering is approximately 70.5 dBA Leq and 87.7 Lmax at a distance of 10 feet. The nearest noise-sensitive receptor on the project site would be located approximately 230 feet and 300 feet from the bleachers at the baseball fields. Based on a 6 dBA reduction per doubling of distance, the unmitigated exterior noise level at the nearest noise-sensitive receptor would therefore approach 62 dBA Lmax and 45 dBA Leq• Potential noise impacts from spectators from Chase Field would not exceed the City's exterior hourly and maximum daytime and nighttime noise standards for residential uses shown above in Table D. Noise associated with the park would be consistent with the traffic noise experienced in the project vicinity. While very rare, typically twice a year at the beginning and end of the baseball season, a public address (PA) system may be used for very short periods of time. Due to the limited use of the PA system, it is not expected to cause any noise impacts. LONG-TERM GROUND-BORNE NOISE AND VIBRATION FROM VEHICULAR TRAFFIC Because the rubber tires and suspension systems of buses and other on-road vehicles provide vibration isolation and reduce noise, it is unusual for on-road vehicles to cause ground-borne noise or vibration problems. When on-road vehicles cause such effects as the rattling of windows, the source is almost always airborne noise. Most problems with on-road vehicle-related noise and vibration can be directly related to a pothole, bump, expansion joint, or other discontinuity in the road surface. Smoothing the bump or filling the pothole will usually solve the problem. The proposed project is located next to roads with smooth pavement. Therefore, vehicular traffic adjacent to the project site would not result in significant ground-borne noise or vibration impacts from vehicular traffic. LONG-TERM OFF-SITE STATIONARY NOISE IMPACTS The proposed project would potentially expose off-site uses to stationary source noise impacts from heating, ventilation, and air conditioning (HVAC) equipment operations. The proposed project would be required to have HVAC equipment such that a windows closed condition is achievable. Based on reference noise level measurements from Trane (2016), an HVAC manufacturer, noise levels from the mechanical ventilation equipment is approximately 55 dBA at a distance of 3 feet. The nearest noise-sensitive receptor is approximately 10 ft west of the proposed project site. Based on a 6 dBA reduction per doubling of distance, the unmitigated exterior noise level at the nearest noise- sensitive receptor would therefore approach 45 dBA Leq. With the quietest existing nighttime noise levels at approximately 53 dBA Leq, operations associated with HVAC equipment would not increase \\ptrll\projects\KPD1702\For DM\Noise Report_10202017.docx (10/23/17) 21 NolSE A.NO VIBRATION IMPACT ANALYSIS OCTOBER 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA LSA existing noise levels by more than 3 dBA and would also be in compliance with the City's exterior daytime and nighttime noise standards for residential uses. SUMMARY OF RECOMMENDATIONS Based on the analysis above, the project would be in compliance with the City of Carlsbad Noise Standards; therefore, no mitigation is required. The project applicant should verify that final design plans reflect the following design features: • The proposed project should include installation of central air conditioning, which allows windows to remain closed. • Standard building construction should consist of wall construction with a minimum rating of STC-46, along with windows with a minimum rating of STC-25 and sliding glass doors with a minimum rating of STC-29. In addition, the following shall be implemented in order to comply with the City's Municipal Code and minimize construction noise impacts: • Construction activities occurring as part of the project shall be subject to the limitations and requirements of the City of Carlsbad Noise Ordinance, which states that construction activities shall occur only between the hours of 7:00 a.m. to 6:00 p.m., Monday through Friday, and 8:00 a.m. to 6:00 p.m. on Saturday. • Prior to project approval, the project proponent shall produce evidence acceptable to the City that: o All construction vehicles or equipment, fixed or mobile, operated within 1,000 feet of a dwelling or noise sensitive use shall be equipped with properly operating and maintained mufflers. o Stockpiling and/or vehicle staging areas shall be located as far as practicable from dwellings and other noise sensitive receptors. \\ptrll\projects\KPDl 702\For DM\Noise Report_10202017.docx (10/23/17) 22 NOISE AND VIBRATION IMPACT ANALVSIS OCTOBER 2017 HARDING ANO PALM TOWNHOUSE PROJECT CITV OF CARLSBAD, SAN DIEGO COUNTY', CALIFORNIA LSA REFERENCES California Department of Transportation (Caltrans). 2013. Transportation and Construction Vibration Guidance Manual. September. __ . Traffic Census Program. Website: http://traffic-counts.dot.ca.gov/ (accessed October 20, 2017). __ . 2017. Transportation Concept Report-Interstate 5. June. Website: http://www.dot.ca.gov/ distll/departments/planning/pdfs/tcr/2017 _TCR_I_S.pdf. (accessed October 20, 2017). City of Carlsbad. General Plan, Noise Element. Website: http://www.carlsbadca.gov/civicax/ filebank/blobdload.aspx?BloblD=24093 (accessed October 2017). __ . Municipal Code, Noise Ordinance. Website: http://www.qcode.us/codes/carlsbad/ (accessed October 2017). __ . Noise Guidelines Manual. September 1995. Website: http://www.carlsbadca.gov/ civicax/filebank/blobdload.aspx?BlobID=24094 (accessed October 2017). Federal Highway Administration (FHWA). 2006. Highway Construction Noise Handbook. Roadway Construction Noise Model, FHWA-HEP-06-015. DOT-VNTSC-FHWA-06-02, NTIS No. PB2006- 109012. August. Federal Transit Administration (FTA). 2006. Office of Planning and Environment. Transit Noise and Vibration Impact Assessment. FTA-VA-90-1003-06. May. Harris, Cyril M., editor. 1991. Handbook of Acoustical Measurements and Noise Control, Third Edition. Harris, David A. 1997. Noise Control Manual for Residential Buildings. July. Karnak Planning and Design. 2017. Harding & Palm Townhouse Project -Plans. August. Milgard. 2008. Sound Transmission Loss Test Report No. TL0B-149. February. Suter, Dr. Alice H.1991. Noise and Its Effects, Administrative Conference of the United States. November. Trane. 2016. Trane TruComfort Variable Speed Systems Product Brochure. United States Environmental Protection Agency (EPA). 1978. Protective Noise Levels, Condensed Version of EPA Levels Document, EPA 550/9-79-100. November. World Health Organization. 1999. Guidelines for Community Noise, edited by Birgitta Berglund, Thomas Lindvall, and Dietrich H. Schwela, April. \\ptrll\projects\KPD1702\For DM\Noise Report_l0202017.docx (10/23/17) 23 N OISE ANO VIBRATION IMPACT ANALYSIS OCTOBER 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALI FORNIA APPENDIX A NOISE MEASUREMENT FIELD SHEETS AND DATA \\ptrll \projects\KPDl 702\For DM\Noise Report_l0202017 .docx 110/23/17) LSA Noise Measurement Survey -24 HR Project Number: =KP=-=D:.......a:..17.:....0=2=-------- Project Name: Harding & Palm Townhouses Site Number: LT-1 Date: 9/27/2017 Test Personnel: Daniel Kaufman Equipment: Quest Noisepro DLX Time: From 10:00 AM To 10:00 AM Site Location: 3535 Harding Street. At the southwestern property line. Primary Noise Sources: -=-T=ra=f=fi=c--=o=n=--=I'""'-5""'. ____________________ _ Noise Measurement Survey-24 HR Project Number: =KP=-=D'--=-17"--0=2=-------- Project Name: Harding & Palm Townhouses Site Number: LT-2 Date: 9/27 /2017 Test Personnel: Daniel Kaufman Equipment: Quest Noisepro DLX Time: From 10:00 AM To 10:00 AM Site Location: 3535 Harding Street. Eastern portion of site, approximately 75 ft southwest of Harding Street. Primary Noise Sources: =T=ra=f=fi=c~o-=n"-=I~-5~.--------------------- Location Photo: Noise Measurement Survey Project Number: '°'KP=-=D""'l:....:7...::0=2'-------- Project Name: Harding & Palm Townhouses Test Personnel: Daniel Kaufman Equipment: Larson Davis 824 Site Number: ST-1 Date: -=--9'-=/2'--'-7 ___ _ Time: From 10:10 AM To 10:30 AM Site Location: 3535 Harding Street. Near the Northwestern property line, about 50 ft west of Harding Street. Primary Noise Sources: ..:.T=ra=f=fi=c--==o=n,....,l'-'-5::...:. ____________________ _ Comments: Tops of autos on I-5 visible. Heavy truck on Harding 67 dBA Filtered airplane 10:13 AM, 10:19 AM, 10:20 AM-10:21 AM. Filtered garbage truck 10:22 Adjacent Roadways: =H=a~rd=i=ng=S~tr~e-=-et'-'-. ____________________ _ Measurement Results A tmosp eric on 1ttons: h ' C d .. dBA Maximum Wind Velocity (mph) 1.5 Leo 58.2 Average Wind Velocity (mph) 4.4 Lmax 69.4 Temperature (F) 76.1 Lmin 51.1 Relative Humidity(%) 58.4 Lneak 88.0 L2 64.0 LR 61.1 L2s 58.5 Lso 56.7 L90 54.4 L99 52.6 Location Photo: Noise Measurement Survey Project Number: "'"KP=-"'D""'l"""'7c...:a0=2'------- Proj ect Name: Harding & Palm Townhouse Test Personnel: Daniel Kaufman Equipment: Larson Davis 824 Site Number: ST-2 Date: ""9/=2:....:..7 ___ _ Time: From 10:35 AM To 10:50 AM Site Location: Near Southeastern property line about 50 ft fromHarding Street. Primary Noise Sources: ..:cT=ra=f=fi=c-"o=n,_,l'-'-5::...:. ____________________ _ Comments: Distant train horns. 10:29 (traffic louder), 10:20 {low 60's dBA), 10:47. Trains indiscernible. Filtered airplanes 10:36 AM, 10:49 AM. On 1-5: Tops of truck visible, cars partially blocked by vegetation, no wall. Adjacent Roadways: =H=a=rd=i=n,.._g""'S"""tr""'e-=-eta.:... ____________________ _ Measurement Results ·c Atmospheric ondltmns: dBA Maximum Wind Velocity (mph) 1.1 Lea 57.9 Average Wind Velocity (mph) 5.6 Lmax. 69.9 Temperature (F) 73.1 Lmin 50.2 Relative Humidity(%) 54.1 ½eak 81.8 L2 63.7 Lg 60.7 L2s 58.2 Lso 56.5 L90 54.1 L99 51.8 Location Photo: NOISE AND VIBRATION IMPACT ANALYSIS OCTOBER 2017 HARDING AND PALM TOWNHOUSE PROJECT CITY OF CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA APPENDIX B INTERIOR NOISE REDUCTION CALCULATION \\ptrll\projects\KPD1702\For DM\Noise Report_l0202017.docx (10/23/17) LSA Analyst: J .T. Stephens 'Hz Fractional Area S/i 1 OA Exterior Wall Wall Assembl Source Area STC 125 250 500 1000 2000 4()()0 125 250 500 1000 2000 4000 I dB tucco David Harris p. 371 147.0 46 27 42 44 46 49 54 0.2933 0.0093 0.0059 0.0037 0.0019 0.0006 a.a 0 0 0 0 0 0 0 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 Milgard 32.0 25 18 16 22 30 30 32 0.5072 0.8038 0.2019 0.0320 0.0320 0.0202 Milgard 33.8 29 19 17 26 33 39 29 0.4249 0.6734 0.0848 0.0169 0.0042 0.0425 o.o 0 0 0 0 0 0 0 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 0.0000 212.72 0.0058 0.0070 0.0014 0.0002 0.0002 0.0003 I ' Room Surface/ Material I Source I Area I NRC I I I I I I I I I I loor -Carpet David Harris p. 34 7 129.0 0.30 0.15 0.17 0.12 0.32 0.52 0.30 19.34 21.92 15.48 41.27 67.06 38.69 loor-Vinyl David Harris p. 347 0.0 0.05 0.02 0.03 0.05 0.03 0.03 0.02 0.00 0.00 0.00 0.00 0.00 0.00 eiing -Drywall David Harris p. 348 129.0 0.50 0.10 0.08 0.05 0.03 0.03 0.03 12.90 10.32 6.45 3.87 3.87 3.87 alls -Drywall David Harris p. 348 425.4 0.50 0.10 0.08 0.05 0.03 0.03 0.03 42.54 34.04 21.27 12.76 12.76 12.76 683.37 74.7848 66.27584 43.1956 57.89944 83.69144 55.32024 76.52 -4.54 -5.06 -6.92 -5.65 -4.05 -5.85 -4.44, ound Source Adjustment Factor -6.00 -6.00 AAMIMliiihiJJHSWil•iii•l=i~I I I I I I I 250 Transmission Loss+ Room Effects+ Adjustment Factor) 11.86 10.49 15.69 24.42 27.42 23.42 1ctave Band Frequency Correction Factors for A-Weighted Sound Levels 16.10 8.60 3.20 0.00 -1.20 -1.00 -Weighted Sound Levels 27.96 19.09 18.89 24.42 26.22 22.42 oise Reduction (dBA) 27.83 18.97 18.77 24.29 26.09 22.29 24.3