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HomeMy WebLinkAboutCT 99-01; Carlsbad Beach Estates; Tentative Map (CT) (41)DOUGLAS EILAR & ASSOCIATES ACOUSTICAL & ENVIRONMENTAL CONSULTING October 22, 1998 Merit Group Attention: David Buckmaster 2172 El Camino Real #202 Oceanside, CA 92054 SUBJECT: REPORT OF RAILROAD NOISE EVALUATION FOR PROPOSED CARLSBAD BEACH ESTATES Dear David: At your request, we have conducted an evaluation of railroad noise levels at the site of your proposed Carlsbad Beach Estates, a residential development, on Chinquapin in Carlsbad. This report is prepared for you to submit to the City of Carlsbad to satisfy city requirements for a noise analysis prior to discretionary approval of your project. Summary Field noise measurements at the project site were made to determine noise levels caused by passing trains. The train schedules and other relevant information with a bearing on noise were obtained. An analysis of total noise exposure throughout different period of the typical weekday was conducted. The results indicate a noise exposure of less than 50 decibels (dB), CNEL, worst case, at the northeast property corner, and lower noise levels elsewhere on subject property, from noise caused by passing trains. There are no other significant noise sources impacting subject property. This noise level is substantially less than the 60 CNEL desired noise limit for residential land uses in the City of Carlsbad. Thus, there is no significant adverse impact from noise, and no mitigation is required. Project Setting Subject property is located on Chinquapin Avenue in the City of Carlsbad. It is approximately 500 feet west of the coastal railroad route and a quarter mile inland from the Pacific Ocean. Less than a quarter mile south is the Agua Hedionda Lagoon. Subject property is located in an older residential neighborhood consisting of single family and multi-family units. Most residential properties in the area are single story or two-story. Filar K A«nriptp<: - ^91 N Willmvsnrino Dr Fnrinitas CA Q?ft?4 - 76(1/7^- Merit Group - Carlsbad Beach Estates Noise Analysis October 22, 1998 Page Two Noise Sources There are no significant noise sources affecting subject property. The closest identified potential noise source is the coastal railroad, which is used by Amtrak for passenger trains, by the North County Transit District for commuter trains, and by Burlington Northern Railway for freight trains. The departure pattern for the McClellan-Palomar Airport is more than one mile south. Other than these, the only other sources of noise are light traffic on nearby residential streets, an occasional plane or helicopter in the distance, residential noises such as lawnmowers, and animals including birds and dogs. The only source with a potential for significance at this property is the railroad, which is the subject of this evaluation. Railroad Operations The current railroad schedules for Amtrak and the Coaster for the nearby stretch of track were obtained. We also contacted a representative of the North County Transit District that owns the railroad right-of-way. He provided additional relevant information about the operations and schedules of all users of the tracks, including the freight trains. Information about the number of cars, train speed, and stops was also obtained. No significant change in future operations is anticipated at this time, so current operations were used as a guide to this analysis. The Coaster operates nine commuter trains in each direction on a typical weekday, for a total of 18. Amtrak operates ten similar trains in each direction nearly every day, for a total of 20. Burlington Northern normally operates an average of four freight trains per day, usually one in each direction during the day and one in each direction late at night. The passenger trains normally run with a single engine and five to eight cars. The freight trains usually have several engines and have from 50 to 100 cars; 75 cars was estimated to be an average. The passenger trains can reach speeds of 60 to 80 mph on open stretches. In this vicinity, however, speeds are less. The Coaster stops to the north at Carlsbad Village and to the south at Poinsettia, so is does not gather much speed here, and passes by at an estimated speed of 25-40 southbound, and somewhat less northbound. The nearest Amtrak stops are in Oceanside and Solana Beach, so these trains do not stop nearby. Their speeds in this area are estimated at 35-50 mph in this area. The freight trains do not stop nearby and are slower, with an estimated speed of 25-30 mph. Filar K A<:<;nHatp« - ~\~>\ N Willmvsnrina T> Fnrinitns PA Q7f)74 - 760/7S'?-! RfiS Merit Group - Carlsbad Beach Estates Noise Analysis October 22,1998 Page Three Since Tamarack Avenue, a block north of Chinquapin, has a railroad crossing, northbound trains sound their horn as they approach and pass Chinquapin, since Tamarack is just ahead. Southbound trains do not, since they have already made their nearest crossing. Consequently, the northbound trains are louder due to the additional noise source of the horn. The approximate times for train pass-bys, based on their current schedules, are: Amtrak - Southbound 08: 10a.m. 09:15 10:32 12:24 p.m. 02:18 04:02 06:03 06:55 09:13 11:41 Amtrak - Northbound 06:57 a.m. 08:53 10:14 11:09 01:01 p.m. 03:43 04:43 06:23 08:28 10:55 Coaster - Southbound 05:29 a.m. 06:13 06:48 07:19 07:48 11:05 03:40 p.m. 05:00 05:30 Coaster - Northbound 07:29 a.m. 08:39 03:08 p.m. 04:32 05:10 05:42 06:14 06:58 07:32 Noise or Sound Level Descriptors All noise level or sound level values presented herein are expressed in terms of decibels (dB), with A-weighting to approximate the hearing sensitivity of humans. Time-averaged noise levels are expressed by the symbol L,, for a specified duration. The Community Noise Equivalent Level (CNEL) is a 24-hour average, where sound levels during evening hours of 7 p.m. to 10 p.m. have an added 5 dB weighting, and sound levels during night-time hours of 10 p.m. to 7 a.m. have an added 10 dB weighting. This is similar to the Day-Night sound level, Ld«, which is a 24-hour average with 10 dB added weighting on the same night-time hours but no added weighting on the evening hours. These metrics are used to express noise levels for both measurement and municipal regulations, for land use guidelines and enforcement of noise ordinances. Filar * A«<:rvriatp<5 -N Willnw«;nrino Dr Fnrinitas PA 97094 - 760/7S1- Merit Group - Carlsbad Beach Estates Noise Analysis October 22, 1998 Page Four Field Measurements On Friday, October 16, 1998, simultaneous noise level measurements during train pass- bys were conducted by two technicians from Douglas Eilar & Associates. The measurements were conducted during the late morning, with fair weather and a very light breeze. The noise level of a southbound Coaster train was measured at approximately 11:07 a.m., and the noise from a northbound Amtrak train was measured at approximately 11:15 a.m. Freight train operations are few and are not on a predetermined schedule, so no freight train measurements were made. Two measurement positions were used, at locations shown in the attached site plan. Position A was near the northeast property corner, at the fence on the eastern property line, about five feet inside the sidewalk. Position B was about five feet inside the southeast property corner. The microphones were at a height of four to five feet above the ground. The instruments used for noise measurements included two type 1 (precision) sound level meters: a GenRad Model 1988 and a Quest Model 1800. Both were calibrated just prior to and immediately after the noise measurements. Both have also been calibrated within the past 12 months by an independent metrology service, in compliance with ANSI standards. During the noise measurements, both units were mounted on tripods and equipped with windscreens. A distance measuring wheel was used to measure all distances. At Position A, the southbound Coaster train at 11:07 a.m. was measured to have a noise level (Leq) of 55.6 dB during the brief passby duration of 20 seconds. The simultaneous measurement of this train from Position B yielded an average noise level during the peak 10 seconds of the passby of 50.3 dB (Leq). At Position A, the northbound Amtrak train at 11:15 a.m. was measured to have an average noise level (Leq) of 61.4 dB over a duration of 40 seconds. It was louder and audible over a longer period in large part to the use of the horn as the train approached the Tamarack Avenue crossing. The simultaneous measurement of this train from Position B yielded an average noise level during the peak 10 seconds of passby at 53.2 dB (Leq). Ambient noise levels at both measurement positions, with no distinctive noises in the background, were approximately 44 dB. All measurements were rather brief for two reasons - the train passbys were quick, and shorter duration measurements minimized the chance of other occasional interfering sound from affecting the results. TVmolac Filar* A««r>Hatp<; - W N Willnwsnrino Dr Rnrinitas PA Q?fP4 - Merit Group - Carlsbad Beach Estates Noise Analysis October 22, 1998 Page Five Analysis The above noise measurements and the frequency, timing, direction and type of train operations were subject to analysis for all operations to arrive at a value for CNEL from the total of all railroad activities. The worst case of the northeast corner of subject property, at Position A was first considered. The noise level of 55.6 dB for 20 seconds per pass for the 14 southbound passenger trains during the 12 daytime hours (between 7 a.m. and 7 p.m.) was averaged, with the result being an hourly average of 34 dB (Leq). (This is based on the general principle in which a 3 dB reduction is applied to convert a given sound intensity to the equivalent intensity over a period twice as long.) The same procedure for the 16 northbound passenger trains (at 61.4 dB per 40-second passby) during this 12-hour period yielded an hourly average of 44 dB (Leq). Freight train noise was estimated to be the worse case of 61.4 dB in each direction, and the duration of a typical freight train was conservatively estimated to be five minutes. Based on this, the two daily passes (one in each direction) during daytime hours yielded an hourly average on 44 dB (Leq). The addition of these three sources results in an hourly average of 47 dB (CNEL) during the 12 daytime hours. In evening hours there is one southbound passenger train and two northbound trains. By similar computation, the hourly average during the three evening hours (7 p.m. to 10 p.m.) is 41 dB (Leq). For CNEL determination, a 5 dB penalty is added to evening noise, resulting in a figure of 46 dB. For the nine night-time hours (between 10 p.m. and 7 a.m.), there are four southbound passenger trains, one northbound passenger trains, and one freight train in each direction. The combined noise level for these operations results in an hourly average of 45 dB (Leq). For CNEL computation, a 10 dB penalty is added, which resulting in a figure of 55 dB. The CNEL for all operations during the 24-hour day is 49.9 dB, as follows: (12 hours x 47 dB + 3 hours x 46 dB + 9 hours x 55 dB) / 24 hours - 49.875 dB Carlsbad Noise Regulations The desirable limit for noise for residential land uses in the City of Carlsbad is 60 dB, CNEL. This figure is used as a guide for the City to determine compatibility of proposed new land uses or developments with existing or anticipated noise levels from transportation of other noise sources. A higher noise level is allowed in certain circumstances, such as within the airport noise contours or in existing areas which already are exposed to high noise levels. When a proposed project is exposed to less than 60 dB, CNEL, it is reasonable to assume that interior noise levels will be less than 45 dB, CNEL. nnnolai Filar # A««nHatp<: - "PI N Willnwsnrino Dr F.nrinitas TA Q7074 - Merit Group - Carlsbad Beach Estates Noise Analysis October 22,1998 Page Six Conclusions The noise levels from railroad operations were calculated for the location on subject property where noise exposure would be loudest. The noise level at. Position B was demonstrated to be less, by measurement, and the noise level elsewhere would also be less, due to the presence of other residential structures between the these locations and the railroad. Since the noise exposure at subject property from railroad activities is determined to be no more than 50 dB, CNEL, at any location on the site, the noise is well below the limit of 60 CNEL stated in the Noise Element to the General Plan for the city of Carlsbad. Thus, there is no adverse impact from railroad noise, and no mitigation is necessary. Please do not hesitate to contact me if you have any questions concerning this analysis. Sincerely, Douglas Eilar & Associates Douglas K. Eilar, Acoustician Principal Investigator DKEielm References and Contacts: 1) City of Carlsbad Noise Element to the General Plan. 2) City of Carlsbad Noise Guidelines, September 1995. 3) North County Transit District, Chris Schmidt, 760/967-2828 4) San Diego Transit Corp, Automated Travel Information System, Eric Anderson Attachments: 1) Assessor's Map showing property location and approximate CNEL contours 2) Reduced site plan, showing sound level measurement locations nr>iiola<: Filar # Assnriatp* - T71 N Willmvsnrincr TV Fnrinitac PA Q9094 - 760/7^- CONDM (UCSHT2)LLEWELLYN SHORES S-00790* 206-06 1 SHTIOF2 IfcJ Irf? J- ,»•** J/ &l*±- FVij; CM/fl 1 HIf B fO **£wr 7»J \MAP 11119-CARLSBAD TCT. NO. 84--26 (CONDM) MAP 1803-FVKLISADES NO. 2MAP 1747-PALISADESPBI PGI53-RHO AGUA HEDIONDA CHINQUAPIN AVE. SCALE,SITE PLAN