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Noise Impact Analysis.pdf• th Street Southwest Corridor • • Project City of Edmonds, Washington Prepared for: The City of Edmonds Edmonds Washington and Perteet, Inc. Everett, Washington Prepared by: Michael Minor c& Associates Portland, Oregon Summary................................................................................................................................... 1 1. Introduction....................................................................................................................... 3 2. Project Description............................................................................................................ 3 3. Land Use........................................................................................................................... 3 3.1. Zoning and Comprehensive Land Use Plan Design ...................................................... 4 3.2. Displacements Due to Project Construction.................................................................. 4 4. Methodology.....................................................................................................................6 4.1. Introduction to Decibels and Traffic Noise................................................................... 6 4.2. Area of Potential Effect................................................................................................. 7 4.3. Regulatory Setting and Impact Criteria......................................................................... 8 4.3.1. Local Noise Regulations....................................................................................... 10 4.4. Noise Monitoring Procedures and Equipment............................................................. 11 4.5. Method of Analysis and Modeling Procedures............................................................ 19 4.6. Selection of Receivers.................................................................................................. 20 5. Existing Environment..................................................................................................... 23 5.1. Existing Noise Environment........................................................................................ 23 5.2. Model Validation......................................................................................................... 24 5.3. Existing Modeled Traffic Noise Levels....................................................................... 24 6. Future Environment........................................................................................................ 26 6.1. Future No -Build Traffic Noise Analysis...................................................................... 26 6.2. Future Build Traffic Noise Analysis............................................................................ 28 6.3. Noise Levels Summary................................................................................................ 31 7. Noise Abatement Analysis.............................................................................................. 35 7.1. Evaluation of Project Traffic Noise Abatement........................................................... 35 7.2. Unavoidable Impacts................................................................................................... 35 7.3. Construction Noise Analysis........................................................................................ 35 7.4. Notification to Local Governments............................................................................. 37 List of Tables Table 1. Noise Abatement Criteria (NAC) by Land Use Category ......................................... 9 Table 2. City of Edmonds Noise Control Regulation............................................................ 10 Table 3. City of Edmonds - Exemptions for Short -Term Noise Exceedance ........................ 10 Table 5. Measured Versus Modeled Noise Levels................................................................ 24 Table 6. Existing Modeled Traffic Noise Levels................................................................... 25 Table 7. Future No -Build Modeled Traffic Noise Levels ...................................................... 27 Table 8. Future Build Modeled Traffic Noise Levels............................................................ 29 Table 9. Summary of Traffic Noise Levels........................................................................... 32 Table 12. Construction Equipment List, Use, and Reference Maximum Noise Levels ......... 36 List of Figures Figure 1. Project Alignment and Land Use............................................................................. 5 Figure 2. Noise Monitoring Location: M-1........................................................................... 12 228th Street SW Corridor Improvements Project May 11, 2012 Figure 3. Noise Monitoring Location: M-2........................................................................... 13 Figure 4. Noise Monitoring Location: M-3........................................................................... 14 Figure 5. Noise Monitoring Location: M-4........................................................................... 15 Figure 6. Noise Monitoring Location: M-5........................................................................... 16 Figure 7. Noise Monitoring Location: M-6........................................................................... 17 Figure 8. Noise Modeling Locations - East........................................................................... 21 Figure 9. Noise Modeling Locations - West.......................................................................... 22 Appendices AppendixA: Contact Records............................................................................................... 38 Appendix B: Introduction to Acoustics................................................................................. 40 Appendix C: Noise Monitoring Data Sheets......................................................................... 46 AppendixD: Bibliography..................................................................................................... 48 AppendixE: Traffic Data....................................................................................................... 49 Appendix F: TNM Files on CD (Hardcopy only).................................................................. 50 228th Street SW Corridor Improvements Project May 11, 2012 The Washington State Department of Transportation requested that a noise analysis be performed for the 228th Street Southwest Corridor Improvements Project. The scope of the project includes extending 228th Street Southwest between 76t1' Avenue West and SR 99. The project would also bring the current median that controls left turns from SR 99 onto 76t1' Avenue West up to American Association of State Highway and Transportation Officials (AASHTO) standards. Completion of the project will reduce congestion and solve key safety issues for vehicles accessing SR 99 by providing protected left -turn phasing for both approaches to the intersection of SR 99 and 228"' Street and eliminating left turns from SR 99 onto 76tt' Avenue West. Pedestrian safety will also be enhanced by the new signal at 228t" and SR 99. A Traffic Noise Analysis is required whenever a Type I project is federally funded or requires FHWA approval. A Type I project is a project that includes construction of a new highway or roadway or an increase in the number of through traffic lanes to, or a substantial realignment (horizontal or vertical) of, an existing highway. The proposed project would include construction of a new roadway and, therefore, is considered a Type I project. Land use in the project area includes single- and multi -family dwelling units, commercial uses, a place of worship, and an interurban pedestrian and bicycle trail. The commercial land uses entail mostly retail and warehousing facilities along SR 99 and a handful of office buildings. None of the commercial uses are exterior uses. The strip of undeveloped land on which the new 228th Street connection to SR 99 will be built is the only undeveloped land in the study area. On-site noise monitoring was performed and used to verify the noise modeling and assist in establishing the existing noise environment. Noise levels were measured at outdoor noise - sensitive land uses. Measured noise levels ranged from 55.5 to 63.7 dBA Leq during these monitoring sessions. The approach level of the traffic noise abatement criteria (Noise Abatement Criteria; NAC) for state and federally funded projects in Washington is 66 dBA Leq for outdoor use at a residence. Receivers are also considered impacted when the worst hourly traffic noise is predicted to increase 10 dBA or more ("substantial increase") between the Existing and Build conditions. The noise analysis was performed for the peals noise hour of the day. Existing conditions, 2035 No -Build Alternative, and 2035 Build Alternative noise levels were predicted for the peals noise hour using the Federal Highway Administration (FHWA) Traffic Noise Model (TNM version 2.5). The traffic noise modeling was performed for fifty- six receiver locations, representative of two hundred twelve residences, the Interurban Trail, and one place of worship within the project corridor. Existing modeled noise levels in the area range from 52 to 66 dBA Leq during the peak noise hour. The highest residential noise levels were modeled at the townhome patios along 76th Avenue West in the Ballinger Park townhome and apartment complex. Receivers R -28/M-3 228th Street SW Corridor Improvements Project May 11, 2012 and R-29 represent these patios. The current modeled noise level at these receivers is 64 and 63 dBA Leq, respectively, which is below the NAC. The modeled noise level at a residential deck represented by receiver R-1, that is near the intersection of 228th Street Southwest and 76t" Avenue West, is also 63 dBA Leq. None of the modeled receiver locations have existing modeled noise levels that meet or exceed the NAC. Under the 2035 No -Build Alternative, noise levels would increase modestly with the expected growth in traffic volumes. Noise levels are expected to range between 54 and 68 dBA Leq during the peak noise hour, which is an increase of up to 3 dB over existing conditions noise levels. Receivers R -28/M-3 and R-29, which represent fifteen patios along 76"i Avenue West at the Ballinger Park townhome and apartment complex, are expected to experience a 3 dB increase. The No -Build modeled noise level at these receivers is 67 and 66 dBA Leq, respectively, which meets or exceeds the NAC. No other receiver locations are expected to have traffic noise levels that meet or exceed NAC. Under the 2035 Build Alternative, traffic noise levels are predicted to range from 55 to 70 dBA Leq during the peak noise hour. These levels constitute an increase of up to 6 dB when compared to the existing noise levels and up to 3 dB when compared to the 2035 No -Build Alternative traffic noise levels. However, due to the proximity of SR 99, which is a relatively high traffic volume roadway, introduction of the 228t" Street connection where currently none exists would not result in any substantial increase traffic noise impacts (defined as an increase of 10 dBA or more above existing conditions). Moreover, no approach level traffic noise impacts are expected under the Build Alternative. Changes in traffic flow caused by the diversion of future traffic from 76tt' Avenue West to the new 228th Street Southwest extension would result in traffic noise reductions at the only two receivers identified with noise levels meeting the NAC under the No -Build alternative. The information contained within this report will inform government officials about the effects of the proposed project and can assist them in their planning process. The project area does not contain any undeveloped land that could be developed in the future, and there are no land use changes, rezones or comprehensive plan amendments currently permitted or under consideration. Based on noise modeling results, any proposed development that conforms to current setbacks should not experience noise levels above the NAC by the year 2035 with construction of the proposed project. If a proposed development involves a change in use from commercial to residential, these setback distances would need to be reexamined. The information provided here should be used as a guideline only. It is based on project area traffic volumes and speeds from the project traffic engineers. A detailed acoustical engineering analysis should be performed for any proposed developments along the project corridor to determine whether the proposed land use would remain compatible with the future noise environment. A discussion of construction noise and potential construction noise abatement measures is included near the end of the report. 2 228th Street SW Corridor Improvements Project May 11, 2012 1 M 10 k I '•0 Is]11 This technical noise analysis for the 228t" Street Southwest Corridor Improvements Project in Edmonds, Washington was prepared as requested by Washington State Department of Transportation. The purpose of this analysis is to identify traffic noise impacts resulting from the proposed project and provide future traffic noise levels that can be used for future land use planning. Where traffic noise impacts are identified, noise abatement is considered and analyzed in accordance with the policy and procedures given in the current WSDOT Traffic Noise Policy and Procedures. Abatement that is found to meet WSDOT criteria will be reviewed by WSDOT and could be recommended for inclusion in the project. 2. PROJECTD CIPTION The project description that follows was provided to Michael Minor & Associates, Inc. (MM&A) on January 19, 2012 by Stephanie Hansen, Senior Community Planner at Perteet, Inc. The project alignment is depicted on aerial photos of the study area in Figure 1. The 228th Street SW Corridor Improvements Project will extend a new roadway, including sidewalks, in the 228th Street SW right-of-way between 76th Avenue W and SR 99. The project will also include two signals (at 228th Street/SR 99 and at 228th Street/76th Avenue W), a large underground stormwater vault, and a median along SR 99 at 76th Avenue W. Existing light poles will need to be relocated, and the project includes removal (and replacement) of an existing stormwater facility. Lastly, the project will overlay 228th Street SW with 2" of hot mix asphalt from the intersection of 80th Avenue West to the Andorra Estates driveway and 76th Ave. W from 228th St. SW to SR 99. Completion of the project will reduce congestion and solve key safety issues for vehicles accessing SR 99 by providing protected left -turn phasing for both approaches and restricting left turns from SR 99 onto 76th Avenue W. The access from 76th onto SR 99 will be improved. Pedestrian safety will also be enhanced by the new signal at 228th and SR 99. The project will facilitate better access to the I-5 Mountlake Terrace Transit Center and to the Interurban Trail located'/2 mile to the east. It will also enhance pedestrian safety by providing a new, signalized pedestrian link that connects the neighborhoods on either side of SR 99.Analysis Requirement A Traffic Noise Analysis is required whenever a Type I project is federally funded or requires FHWA approval. A Type I project is a project that includes construction of a new highway or roadway or an increase in the number of through traffic lanes to, or a substantial realignment (horizontal or vertical) of, an existing highway. The proposed project would include construction of a new roadway and, therefore, is considered a Type I project. . LAND USE Land use in the project area includes single- and multi -family dwelling units, commercial uses, and a place of worship. The multi -family residential land uses are mostly located along (a) 76th Avenue West on the east side of SR 99 and (b) the south side of 228th Street Southwest on the west side of SR 99. The Church of Jesus Christ of Latter Day Saints is located on 228th Street Southwest, between 78th Avenue West and 80t" Avenue West. 228th Street SW Corridor Improvements Project May 11, 2012 Otherwise, to the east of 76th Avenue West and to the west of 781h Avenue West, single- family homes are the predominant land use. Commercial uses are dominant in the corridor along SR 99 in between 76th Avenue West and 78th Avenue West. The Interurban Trail runs roughly parallel with, and approximately a quarter mile to the east of, SR 99 through the project area. The existing commercial land uses in the project corridor include retail and warehousing facilities (FHWA activity category F) all along SR 99 and office buildings (FHWA activity category E) on each of the northeast and northwest corners of the intersection of 76th Avenue West and 228th Street Southwest. The building on the northwest corner is next to the undeveloped land on which the new 228th Street connection to SR 99 will be built. Other than this strip of undeveloped land, there are no other FHWA activity category G uses in the study area. There are also no FHWA activity category A or D land uses located in the project corridor, and none of the commercial/retail structures in the study area have exterior uses. Figure 1 is an aerial view of the project corridor with the proposed roadway improvements and the different land use types identified. 3.1. Zoning and Comprehensive Land Use Plan Design A study of the project area indicated that there are no new residential or commercial developments under way in the vicinity of the project. Because this project includes three jurisdictions, The City of Edmonds, Snohomish County and the City of Mountlake Terrace, all three were contracted to review any permitted uses in the corridor and to obtain general land use information. The City of Edmonds Planning Division was contacted to verify land use in the project area study, including existing tax lot and zoning information, and to ascertain the status of any potential future developments, including residential and commercial units. According to Michael Clugston, a planner at the City of Edmonds Planning Division, there are no permitted projects in the project study area other than normal course home remodels, and there are no land use changes, rezones or comprehensive plan amendments currently permitted or under consideration. Likewise, the Snohomish County Planning & Development Services was contacted, and Darryl Eastin, the county's Principal Planner, informed us that there are no proposed or pending land use changes, rezones or comprehensive plan land use changes in the study area. Finally, according to Paula Schwartz, a planner for the City of Mountlake Terrace, which also has jurisdiction over a portion of the project study, there are no land use changes planned or permitted in the city's portion of the project corridor. Contact records for all of the land use related communications are provided in Appendix A. There are no displacements planned as part of this project that would have any effect on the area traffic noise levels, potential impacts or overall noise environment. 228th Street SW Corridor Improvements Project May 11, 2012 ,�� / �� w. { � / //� ilaY/�l ��> hGH/' in< ,-„ qtr 4 ,wa fi�l ilr„�i> �� Sly � � iVrr � �' ,�wiv/�1�� l �� + � `/A % 1 i %//f ��J��/ ; V /poi � /� �/i f %� - rq f / �i I�,��/ ��J if �If �J I �// l�a � f � � % J/ /i� �r Oi 1�J� � >, �� i iii II ifl i � ,” "11 , ';,,� 1 r i /� r��/�I�JJ/��ril�/6" i Nfe �f///yY'�Ip��%g/ )/ ,��r a (y�/ J �� dti ,./� i • � �� r �/ /� �� „, �I r! ! � � � � ;; i1�f��G�i �r � �/ � l� �� , /if ©� IVB �; � ;,:1 � f�ii �� ! �Il r u Ile U � / � ..� � .�IfI/ �� , �� v �,� ,,,��,�ol� � n/;� u ?„"” � I ;, �Yl� �� r' l � i fY � � "rI'2 ��f,�) � ��/x � o„i> ,i �a,y,, (r ar1�/�/ � � /'� �/ ice, is r � �� , ��,, /;� iy �iy, ,1 ,!> � ��/,, � I fiJ I'Cir�� 1y ��' y 1%� �� /%' uu i l f�� /�� ,, lI f � f y / i � r // sir/' j/ � �� /� � !"�/' l ,/.�f/ , 1//� /f /r%�� )�/%A� i N� W ili;.' / '% � i / / � , yy i (h /� �� l , II� N Y�40 lw � I �I � W,�1/ � ��” A�y' � y �R?�VI�� i/ ✓� !� �� y � 1. // �// �� 1 /� ��l Fl ��f /` %/ � �f� � / v� ,y /� ��f11 / A � � � i hl l � � / /// f (A I l � l �•�. �f ' {IQjr ��V � /J�Gl i � 1 � � � �� 41 � I f � G � 1� n f� p �, � r J / �/ l � � � �; 7 � ✓ �� 7 �� / � , / f �%�� rm ��/ 11 ��/ .A fl n /I� f / �r f � l / fY M � Y / � J/ �� )' %� / � / / /� l �� t W D i, � �( i i i % �, � k /i tl�� 5 � � f �� /� fJ,''rTM' //� tftdii �, � �� r Qir �>l�% r�, � ,✓ / l/ 1 �, � 1 n � i $ �� y> i � � � � � i/ /� r � e 'l� rd % rY�,� I � "�, � t r � � /� � ��'� h fj/ � N4 ///, � / r �P �� G� 1r �j//� l � f ♦ p/�/�,,J � �$ �u+l � / � I� ��f ��r�%A /1 ry,�� llri' � ,I � j1 /r i��%,��f�il ��l y: ,�V. ..11 � I� /�� $f � �� vv( l � 1 r / I r / / 11 � � 1 � ✓. � �� . � lW l/. %�/ � 1. � ill %/1 Q�'IY,V��,yMl'" � �p%;;��! � f IP 1' b � / � J / ! 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A complete detailed introduction to acoustics is provided in Appendix B. Noise is generally defined as unwanted sound. Noise is measured in terms of sound pressure level. It is expressed in decibels (dB), which are defined as 10 log P2/P2ref, where P is the root -mean -square (rms) sound pressure and Pref is the reference rms sound pressure of 2 x 10-5 Newtons per square meter. The number of fluctuation cycles or pressure waves per second of a particular sound is the frequency of the sound. The human ear is less sensitive to higher and lower frequencies than to mid-range frequencies. Therefore, sound level meters used to measure environmental noise generally incorporate a weighing system that filters out higher and lower frequencies in a manner similar to the human ear. This system produces noise measurements that approximate the normal human perception of noise. Measurements made with this weighing system are termed "A -weighted" and are specified as "dBA" readings. The minimum noise level during a measurement period is denoted L",in. The maximum noise levels (L,,,ax) that occur during an event, such as the passing of a heavy truck or the flyover of an airplane, can be useful indicators of interference with speech or sleep. Several noise descriptors are used that take into account the variability of noise over time. The equivalent sound level (Leq) is the level of a constant sound for a specified period of time that has the same sound energy as an actual fluctuating noise over the same period of time. It is an energy average sound level. Another descriptor, the statistical sound level, is the sound level that is equaled or exceeded for a specified percentage of a given measurement period. For example, L90 is the notation for the noise level within a measurement interval that is equaled or exceeded 90 percent of the time. In summary, the noise level descriptors are defined as follows: Symbol Description Le The average noise level (energy basis) Lmfn The minimum noise level Lmax The maximum noise level LX The noise level that is equaled or exceeded for 'Y' percent of the time Noise levels decrease with distance from a noise source. Noise levels decrease by approximately 6 dBA for each doubling of the distance from a point source in free space. This is due to the geometric divergence of the sound waves and is commonly known as the 6 228th Street SW Corridor Improvements Project May 11, 2012 inverse square law. Excess noise reduction (attenuation) can be provided by vegetation, terrain, and atmospheric effects that block or absorb noise. The Leq noise level from a line source (such as a busy road or highway) will typically decrease by 3 dBA for each doubling of distance. However, the L,,,a,,� from individual vehicles on the road typically decrease by approximately 6 dBA for each doubling of distance. Therefore, the maximum noise levels (Ln,ax) decrease more rapidly with distance from the road than do the average noise levels (Leq) Subjectively, a 10-dBA change in traffic noise level is judged by most people to be approxi- mately a twofold change in loudness (e.g., an increase from 50 dBA to 60 dBA causes the loudness to double). A 3-dBA increase in traffic noise level is a barely perceptible increase to most people, and a 5 dBA change in traffic noise is noticeable to most everyone. 4.2. Area of Potential Effect The area of potential effect for a proposed project does not always coincide with the project's geographical limits. Modeling to identify the area of potential effect is done in conjunction with the regular noise modeling for a proposed project. Representative receivers and/or receivers at regular distance increments are used in the modeling process to ascertain whether impacts will occur under the Build Alternative that are not also expected under the No -Build Alternative. Under normal circumstances, modeling results for the future No -Build and Build Alternatives are compared to see at what point beyond the project's limits these results are the same. When the No -Build and Build Alternative modeling results are essentially the same in a given area beyond the project's limits (typically 3 dB or less), it can be concluded that the proposed project will not have an effect on the noise levels in that area. Where substantial increase traffic noise impacts (defined as an increase of 10 dB or more above existing conditions) are possible, such as in situations where there is a new roadway being constructed, additional monitoring may also be required in order to determine the outer limit of those impacts. In all cases, WSDOT specifically requires that modeled receivers shall extend beyond the distance where impacts can be modeled to verify that the full impacted area is captured. The project corridor is located in the City of Edmonds, Washington and the improvement limits extends east to west along 228th Street Southwest, starting at 78th Avenue West and extending eastward to just east of 75th Avenue West. The project is also expected to provide a pavement overlay on 228th Street from 80tt' Avenue West to the entrance to Andorra Estates, on Lakeview Drive; however, the overlay section is not considered a roadway improvement and therefore not considered in this noise analysis. The areas along both sides of 228th Street Southwest and 76th Avenue West were modeled for effects from traffic noise. In addition, results from receivers situated beyond the project's geographical limits were analyzed to determine the area of potential effect. Specifically, 228th Street SW Corridor Improvements Project May 11, 2012 front-line' and second -line receivers were located 650 to 1000 feet beyond the project's limits of improvements on the east and west ends of 228th Street Southwest and the south and north ends of 76th Avenue West. Monitoring was also conducted at some of these receiver locations in order to verify the traffic noise models. Section 6.1 contains the monitoring and model validation results. Section 7.3 contains a summary of all of the modeling results for this noise study, including a comparison of the No -Build and Build Alternative results referred to above. From the modeling results at receivers R -3/M-1, R-4 and R-5, it can be seen that for the apartment homes along76t" Avenue West that are north of 228th Street Southwest, no impacts will occur as a result of the project, and 2035 No -Build and Build traffic noise levels will be virtually identical. Further north than this, the noise environment is dominated by traffic on SR 99 and is not affected by the proposed project. For the homes along76th Avenue West that are south of 2281h Street Southwest, the modeling results from receivers R-23 through R-29 reveal that 2035 Build traffic noise levels will actually be less than No -Build noise levels and no impacts will occur at this end of the study area. Because east -west traffic that is currently forced to use 76th Avenue West in order to cross SR 99 will instead be able to directly cross SR 99 using the new 228th Street Southwest extension under the Build Alternative, traffic noise levels at the homes in the south end of the study area are expected to decrease under the Build Alternative when compared to the No -Build Alternative and increase by no more than 2 dB when compared to existing conditions noise levels. Receiver locations at the eastern and western ends of the corridor were also modeled to ascertain the limits of the area of potential effect. The proposed extension would produce slightly higher traffic noise levels to residences located along 228''' Street Southwest due to an expected increase in traffic volumes. However, the modeling results in these areas demonstrate that the receivers used were adequate to fully define the area of potential effect for the proposed project, and no impacts are expected at either end of the project. 4.3. Regulatory Setting and Impact Criteria The FHWA traffic noise impact criteria, against which the project traffic noise levels are evaluated, are taken from Title 23 of the Code of Federal Regulations (CFR) Part 772, Procedures for Abatement of Highway Traffic Noise and Construction Noise. The FHWA criterion applicable for residences is an exterior hourly equivalent sound level (Leq) that approaches or exceeds 67 dBA. The exterior approach level criterion for places of worship, schools, recreational uses, and similar areas is also 67 dBA Leq. The criterion applicable for hotels, motels, offices, restaurants/bars, and other developed lands is an exterior Leq that approaches or exceeds 72 dBA. There are no FHWA traffic noise impact criteria for retail facilities, industrial and warehousing uses, undeveloped lands that are not permitted, or construction noise. No analysis of traffic noise impacts is required for those uses for which no criteria exist. ' For the purpose of this report, "front-line" refers to noise sensitive receivers (or receptors) located directly adjacent to the project roadway and "second -line" refers to noise sensitive receivers (or receptors) located behind the front-line receivers/receptors such that there is a front-line receiver/receptor between the second -line receiver/receptor and the project roadway. 8 228th Street SW Corridor Improvements Project May 11, 2012 WSDOT considers a predicted sound level of 1 dBA below the NAC as sufficient to satisfy the condition of "approach", or approaching the NAC, required by FHWA for all land use categories. For example, where the NAC is 67 dBA Leq for outdoor use at a residence, a noise level of 66 dBA Leq is considered an impact. Receivers are also considered impacted when the worst hourly traffic noise is predicted to increase 10 dB ("substantial increase") or more between the Existing and Build conditions. Impacts at places of worship, schools, and recreational areas (category C properties) also occur at 66 dBA Leq or higher in Washington. Hotel/motel, office building, and restaurant/bar impacts (category E property) occur at 71 dBA Leq or higher. Table 1 summarizes the FHWA and the WSDOT traffic noise abatement criteria. Table 1. Noise Abatement Criteria (NAC) by Land Use Category Activity Criteria in Activity hourly Leq (dBA) _ _ , v Evaluation Activity Description Category FHWA WSDOT Location NAC NAC Lands on which serenity and quiet are of extraordinary significance and serve an important A 57 56 Exterior public need and where the preservation of those qualities is essential if the area is to continue to serve its intended purpose B' 67 66 Exterior Residential (single and multi family units) Active sport areas, amphitheaters, auditoriums, campgrounds, cemeteries, day care centers, hospitals, libraries, medical facilities, parks, picnic areas, places of worship, playgrounds, C1,67 66 Exterior public meeting rooms, public or nonprofit institutional structures, radio studios, recording studios, recreation areas, Section 4(f) sites, schools , television studios, trails, and trail crossings Auditoriums, day care centers, hospitals, libraries, medical facilities, places of worship, D 52 51 Interior public meeting rooms, public or nonprofit institutional structures, radio studios, recording studios schools, and television studios Hotels, motels, offices, restaurants/bars, and E' 72 71 Exterior other developed lands, properties or activities not included in A -D or F Agriculture, airports, bus yards, emergency services, industrial, logging, maintenance F -- -- -- facilities, manufacturing, mining, rail yards, retail facilities, shipyards, utilities (water resources, water treatment, electrical), and warehousing Gdevelonds that are not permitted Undeveloped laed _. w _ .__ _ _ 228th Street SW Corridor Improvements Project May 11, 2012 Notes: 1. Includes undeveloped lands permitted for this activity category There are no category A or D, land uses located in the project corridor and none of the category E uses are exterior to the structure. While undeveloped parcels, regardless of zoning, are not considered noise sensitive and, therefore, do not require a traffic noise impact analysis, undeveloped parcels that have an approved building permit at the time the project has been publicly announced are analyzed based on the proposed use. As previously stated, no permits have been issued by the City of Edmonds or Snohomish County for any new developments. 4.3.1. Local Noise Regulations The City of Edmonds City Code Chapter 5.30 would apply to the construction of the proposed project. Under Section 5.30.110, sounds originating from temporary construction sites as a result of construction activity are exempt from regulation in the City Code during the normal daytime hours of 7:00 a.m. to 6:00 p.m. on weekdays and 10:00 a.m. to 6:00 p.m. on Saturdays, excluding Federal Holidays. Therefore, project construction could be performed during these hours. If construction were to be performed during any other others (e.g., nighttime hours), the contractor would be required to either meet the noise -level requirements presented in Table 2 (adjusted in accordance with the Table 2 footnote) or obtain a noise variance from the governing jurisdiction. In addition to the property -line noise standards listed in Table 2, there are exemptions for short-term noise exceedance that occur at any hour of the day or night, including those outlined in Table 3, that are based on the minutes per hour that the noise limit is exceeded. The Washington Administrative Code (WAC), Chapter 173-60 would normally also apply to a project such as this, but the City of Edmonds Code is more stringent and, therefore, supersedes the state regulations. Table 2. City of Edmonds Noise Control Regulation Minutes Per Hour District of Receiver of Noise District Of (Maximum Allowable Sound Level in dBAa) Source of Noise Sou +10 dBA 1.5 Residential Business Commercial Residential 55 57 60 Business 1 57 60 65 Commercial 1 60 65 70 a Between 10:00 p.m. and 7:00 a.m., the levels given above are reduced by 10 dBA for residential receiving property. Table 3. City of Edmonds - Exemptions for Short -Term Noise Exceedance Minutes Per Hour Adjustment to Maximum Sound Level 15 +5 dBA 5 +10 dBA 1.5 +15 dBA 10 228th Street SW Corridor Improvements Project May 11, 2012 ■ 111 11101 • • • , On-site noise monitoring and traffic counts were performed and used to verify the noise model and assist in establishing the existing noise environment. Noise levels were monitored at six sites. The sites are designated M-1 through M-6. Figures 2 through 7 include aerial views and photos showing the exact location of the monitoring sites. The monitoring sites are also identified on an aerial view of the entire project corridor in Figures 8 and 9 of Section 5.5. Monitoring location M-1 was chosen to verify noise levels at residences in the northern portion of the project area that are located along 76th Avenue West and, in some cases, also have a direct line of sight to SR 99. Monitoring location M-2 was chosen to verify noise levels on the Interurban Trail and in the backyards of homes that have a direct line of sight to 228th Street Southwest. Monitoring location M-3 was selected to verify noise levels at townhome patios in the southern portion of the project area. Monitoring location M-4 was chosen to verify noise modeling accuracy for those homes located in the near western half of the project corridor that also have a direct line of sight to 228th Street Southwest. Monitoring location M-5 was chosen to verify noise levels at the medical office located at the northeast corner of the intersection of 76th Avenue West and 228th Street Southwest. This site is directly across from the undeveloped land on which the new 228th Street connection to SR 99 will be built. Monitoring location M-6 was selected to verify noise levels at the western edge of the project area. The sound level meter used for the measurements was a Bruel & Kjaer Type 2238. The sound level meter meets or exceeds American National Standards Institute (ANSI) 51.4-1983 for Type I Sound Measurement Devices. All measurement procedures complied with FHWA and WSDOT methods for environmental noise measurements. System calibration was performed before and after each measurement session with a Bruel & Kjaer Type 4231 sound level calibrator. Noise measurements and traffic counts were performed for fifteen minutes at each of the monitoring locations. The traffic count on SR 99 that was used for monitoring locations M-4 and M-5 was taken during a fifteen minute interval between those sessions. In each case, the traffic data was normalized to one hour by multiplying the traffic counts by a factor of four (4). Table 4 lists each monitoring location and the approximate distance of that location from the centerlines of nearby roadways, the relevant measuring period, the roadways on which traffic is a contributing noise source, traffic counts for contributing roadways, and the measured noise level at that location. 11 228th Street SW Corridor Improvements Project May 11, 2012 12 czamStreet ovvCorridor Improvements Project May 11.un1u 7Cr'771�r�# l� _Gl ��a1r►Ci7 i7 i i�7l lid � RTI1 [�7 �F■►�C�! 13 228th Street SW Corridor Improvements Project May 11, 2012 � /✓fig/ � �l % � / �J/�� "i 1, / J) / Y 13 228th Street SW Corridor Improvements Project May 11, 2012 r, _, � r'�l � 1'f[+7if`��7PiTfL■�C�Z�TiTC�171iT■UIQ�: 14 228th Street SW Corridor Improvements Project May 11, 2012 15 228th Street SW Corridor Improvements Project May 11, 2012 16 228th Street SW Corridor Improvements Project May 11, 2012 .7(�"'I1T'�� r-_Cr7�r71►iC�77i'�i•T'i7 �T_•". ■ t�Z�TI �l C�71F■ i�ld+ 17 228th Street SW Corridor Improvements Project May 11, 2012 Table 2. Noise Monitoring and Contributing Roadway Traffic Counts Monitoring Traffic Counts from Roadways that Contribute to Sound Location Sound Traffic Noise Levels at Monitoring Location Level and Level No. Distance from Meas. Roadway NB/EB2 SB/WB2 (dBA L eq) Roadway Period Name Centerline' PV MT HT PV MT HT 22707 76th 76th Ave. NB 168 4 4 - - - Ave... 76th Ave. SB - - - 136 12 0 M-1 (Ballinger 4/9/2012 59.5 Court Apts.) SR 99 NB 872 12 8 - - - (47 feet from 76th Ave.) SR 99 SB - - - 892 28 12 228th St. 156 8 4 - - - Interurban EB Trail (along 228th St. M-2 228th St.) (53 4/9/2012 WB - - - 148 4 4 59.9 feet from 228th St.) SR 99 NB 872 12 8 - - - SR 99 SB - - - 892 28 12 76th Ave. 216 12 0 - - - NB 22924 76th 76th Ave. Ave. (Park SB - - - 184 8 4 M-3 Ballinger) (37 4/9/2012 63.7 230th St. 36 0 0 - - - feet from 76th Ave.) WB 230th St. - - - 48 0 0 EB 7818 228th 228th St. EB 80 16 0 - - - St. (Taylor 228th St. WB - - - 84 0 0 M-4 Place 4/9/2012 58.2 Condos) (43 SR 99 NB 1116 16 12 - - - feet from 228th St.) SR 99 SB - - - 968 20 0 228th EB 172 4 0 - - - 228th WB - - - 116 8 0 76th Ave. NB (S. of 300 12 0 - - - 228th) 76th Ave. 22721 228th St. (38 feet NB (N. of 260 8 0 - - - M 5 from 228th 4/9/2012 228th) 62.6 76th Ave. St.; 75 feet from 76th SB (N. of - - - 172 4 0 Ave.) 228th) 76th Ave. SB (S. of - - - 164 8 0 228th) SR 99 NB 1116 16 12 - - - SR 99 SB - - - 968 20 0 18 228th Street SW Corridor Improvements Project May 11, 2012 M-6 228th St. 76 0 0 - - - EB 22728 80th 228th St. _ _ _ 132 0 0 Ave. (43 feet 4/9/2012 WB from 228th 80th Ave. 44 0 0 St.) NB - - - 80th Ave. _ _ _ 32 0 0 SB 55.5 Notes: 1. All monitoring was performed on April 9, 2012. 2. PV = passenger vehicles and light trucks (2 axels & 4 tires); MT = medium trucks (2 axels & 6 tires), such as FedEx delivery trucks; and HT = heavy trucks (3 or more axels), such as long haul tractor trailers and dump trucks. These are one-hour counts based on 15 minute periods. 3. One-hour Leq in dBA based on 15 minute measurement periods 4. Observed speeds during measurements: 76th Ave.: 25 mph; SR 99: 35 mph; 228th St.: 25 mph; 230th St.: 25 mph; 80th Ave.: 25 mph 5. Data sheets are provided in Appendix E. Traffic on 76th Avenue West was the dominant noise source at monitoring locations M-1 and M-3. Traffic on 228th Street Southwest dominated the noise environment at all of the other monitoring locations. Traffic on 76th Avenue West also contributed to the noise environment at M-5. Measured noise levels ranged from 55.5 to 63.7 dBA Leq. The highest noise level measured was at measuring location M-3, which represents the southernmost townhome patios in the Ballinger Park townhome and apartment complex. Traffic on 230th Street Southwest contributed to noise at this location. There was no noticeable noise from any industrial or commercial activities during the noise measurement periods. There was an emergency vehicle drive-by and noise from a lawnmower at location M-2. The emergency vehicle siren was removed from the measured data. Noise from an idling car was experienced at location M-1 and from a gas powered leaf blower at location M-3. While this noise affected the monitoring data, removing it was not necessary to validate the models. Appendix C contains noise monitoring details including measured data, local topographical conditions, and distances from each monitoring location to the nearest roadways. The methodology used for a Type I traffic noise analysis is defined in the current WSDOT Traffic Noise Policy and Procedures and the United States Department of Transportation (USDOT) Federal Highway Traffic Noise Standards (Title 23 of the Code of Federal Regulations (CFR) Part 772, Proceduresfor Abatement of Highway Traffic Noise and Construction Noise). A bibliography of the technical support documents used for this report is in Appendix D. Projected traffic noise level conditions were calculated using the FHWA Traffic Noise Model (TNM version 2.5 - USDOT, 2004), developed for FHWA. Prior to predicting the existing and future noise levels, the traffic noise model was verified using actual traffic counts and measured noise levels. Noise emission levels used in the model were nationwide averages for automobiles, medium trucks, and heavy trucks provided by the FHWA and built into the TNM. The area was evaluated for noise reducing effects of front-line residences, existing 19 228th Street SW Corridor Improvements Project May 11, 2012 outbuildings, roadway depressions and topography, all of which were included in the model where appropriate. To ensure TNM accurately predicted traffic noise from the project roadways, FHWA guidelines were followed, and with one exception, each lane was modeled separately. The one exception to modeling each lane separately was combining the middle and outside lanes of SR99, and locating this single lane where the actual lanes meet. This method was used because a site visit revealed that the outside lanes on these roadways are used overwhelmingly for ingress to and egress from local businesses along the roadway and are avoided by through traffic. The validity of modeling in this manner was verified by the validation process. Existing and proposed roadway alignments, the actual width of roadway pavement for the existing and future conditions, and average pavement type were used in the model. Traffic volumes and vehicle class percentages used for the modeled roadways are based on several traffic -related documents provided by David Schuurman, Transportation Analyst at Perteet, Inc. The vehicle speeds used are the current posted speeds. The peals vehicle hour was used throughout the analysis to ensure that the worst-case noise levels were predicted. The pertinent pages of the documents provide to MM&A for this project are provided in Appendix E. 4.6. Selection of Receivers Existing and future noise levels were predicted using the TNM computer model. Figures 8 and 9 show the noise modeling locations used for this report on aerial photos of the study area. 20 228th Street SW Corridor Improvements Project May 11, 2012 00 UJ ' n ��" ry , , { / 1 �� +J a, � �l/ yq iJ %Il �r'{�f'�„ /„f �I)r� b iy /// ft� i� T'��Ifjf�%�') �I, • ':. �JJ/�)�jj i u , y CL • • �� al"r""�*�l�i �19't� r 'j � '„r�, � x,p: (�� b �h • /%ri, ll �y�l�� „ f h � { y�� . 0 v(� ��rrly i , � � r/ � r!/3a r ✓ i r'i ( J” , D/ �� P� a �iJ �'%�' �{ / �✓ .0 cqP cq t r r penv I J/ 1Y?( r fl1J f g � 4 I 4 MLL • . r. R i � f 4 P ( r+ , 00 r t /%/(/ �,,,��, �7`�� y�!)ekiv}"�W�� / 'kS'�:' d I J'0 " q ✓� /� J �jJ // .r n�/ N J Y ��/ v'�h�1jV�"�/N W �I 4 I i+�'/l/� i✓.' � � Fr� "I I � Y� l� /��i � f �kdtiY� � Q N h r z / ✓ /, /,� / /i � �� , , � ,/ �,rd �/ ply �✓� '�/� "' I��y'� Yw� / �� ( ,� � � v' D,v; q Iwo / � � k ( /wiz ✓ i r � / r �% rl../�✓fr % // Ijy ,: d� / ��j �� /r(1 f 1� J!! y A 0 d f 1. �l y / r I ��✓/ 'k / ` N V rr „ I s Fifty-six (56) representative receiver locations were utilized for this noise study. All of the receivers were selected based on the requirements established by the FHWA and WSDOT. For traffic noise studies, the noise modeling location must represent the outdoor use of the property. Multi -floor receivers were used at the Park Ballinger Apartment and Townhome complex where each ground level apartment has a patio and each non -ground level apartment has a balcony (e.g., locations R-30 (lower), R-30 (middle) and R-30 (upper)). Where receiver locations coincide with monitoring locations, both designations are displayed (e.g., R -3/M-1). All of the modeling locations represent an area of frequent, outdoor, residential use with the exception of M-4, M-5 and POW -1. Location M-4 represents the landscaped area in front of the Taylor Place Townhome Condominiums located at 7818 228th Street Southwest and was used to validate the model. Each of the condominiums has its own patio but none of these were accessible during the monitoring period. The patios have separate receivers assigned to them (R-33, R-34, and R-35). M-5 represents the medical office located at the northeast corner of the intersection of 76th Avenue West and 228th Street Southwest. This site is directly across from the undeveloped land on which the new 228th Street connection to SR 99 will be built. The medical office does not have an outdoor use but the location was used to validate the model. The medical office is in a shared building with a home, and the home has a deck in the backyard that has a direct line of sight to 76th Avenue West and is represented by receiver R-1. POW -1 represents the Church of Jesus Christ of Latter Day Saints located at 7920 228th Street Southwest. Receiver R -14/M-2 represents an interurban pedestrian and bicycle trail as well as two homes whose yards abut the trail. A total of two -hundred and twelve (212) homes are represented by the modeled receivers. The study area consists of single- and multi -family residential uses, commercial uses, a place of worship, and an interurban pedestrian and bicycle trail. 5.1. Existing Noise Environment In the center of the project corridor, which is where the new 228th Street Southwest connection would be constructed, traffic on SR 99 is the dominant noise source. However, at distances progressively farther east and west from SR 99, noise from traffic on that roadway dissipates, and traffic on 76th Avenue West, 228th Street Southwest, and ancillary roadways plays an increasingly greater role in neighborhood noise levels. Non -traffic related noise sources, such as emergency vehicle sirens, lawn care equipment, and road improvement equipment operating on a temporary basis, were evident during on- site monitoring visits, but there was no significant noise heard from industrial or commercial sources. Aircraft overflights were noted during the on-site visit, but they did not produce any noticeable noise. There is a steady change in elevation on SR 99, which slopes downward when travelling north through the study area. 76th Avenue West has a similar pattern south of 228th Street Southwest and then levels out as it runs into SR 99. The change in elevation on 228th Street Southwest is more uneven, but in general, the roadway slopes downhill from 23 228th Street SW Corridor Improvements Project May 11, 2012 west to east in the study area. The extension itself will drop ten feet between the intersection with SR 99 and 76th Avenue West. Prior to performing the traffic noise analysis, the traffic noise levels were modeled to test the agreement of calculated and measured noise levels. Traffic volumes and speeds observed during the noise monitoring were used as input to the model. Distances from monitoring locations to roadway centerlines were measured using physical methods and existing graphics files. A comparison for the six monitoring locations is contained in Table 5. Table 5. Measured Versus Modeled Noise Levels Receiver Measured dBA Le Modeled (dBA LQ) Difference in dB M-1 59.5 57.5 2.0 M-2 59.9 58.1 1.8 M-3 63.7 62.5 1.2 M-4 58.2 59.4 -1.2 M-5 62.6 62.8 -0.2 M-6 55.5 55.6 1 -0.1 The modeled and measured noise results agree within +2.0 to -1.2 dB for the locations used in the validation. WSDOT considers an agreement of +/- 2 dB or less to be acceptable for modeled and measured noise level deviations. The TNM modeling files used to compare the noise monitoring results are provided in Appendix G. .3. Existing Modeled Traffic Noise Levels This section provides the noise modeling results for the peals -traffic noise hour. Modeling was performed for all fifty-six (56) representative receiver locations selected. The existing modeled noise levels in the project area range from 52 to 66 dBA Leq during the peak -traffic noise hour. No receivers have modeled traffic noise levels that meet or exceed the NAC. In general, the homes with the highest noise levels are located adjacent and have a line of sight to the project roadways. The TNM modeling files are provided in Appendix G. Table 6 provides a summary of the existing modeled traffic noise levels for these receivers. 24 228th Street SW Corridor Improvements Project May 11, 2012 Table 6. Existing Modeled Traffic Noise Levels Receiver' Uses 2 Represented Land Use Activity Category3 Land Use Sound Level in Leq(dBA) 6 6 Criteria Existing Properties with Noise Levels Meeting NAC' M-5 0 E Com 71 66 R-1 1 B Res 66 63 R-2 6 B Res 66 62 R -3/M-1 3 B Res 66 61 R-4 5 B Res 66 61 R-5 80 B Res 66 60 R-6 8 B Res 66 61 R-7 1 B Res 66 60 R-8 1 B Res 66 60 R-9 1 B Res 66 58 R-10 1 B Res 66 58 R-11 2 B Res 66 56 R-12 2 B Res 66 56 R-13 1 B Res 66 56 R -14/M-2 3 B and C Res & Trail 66 60 R-15 4 B Res 66 55 R-16 3 B Res 66 56 R-17 4 B Res 66 57 R-18 2 B Res 66 59 R-19 1 B Res 66 62 R-20 1 B Res 66 62 R-21 2 B Res 66 59 R-22 4 B Res 66 54 R-23 4 B Res 66 54 R-24 4 B Res 66 53 R-25 2 B Res 66 58 R-26 1 B Res 66 60 R-27 1 B Res 66 62 R -28/M-3 9 B Res 66 64 R-29 6 B Res 66 63 R-30 lower 10 B Res 66 57 R-30 middle 9 B Res 66 60 R-30 (upper) 9 B Res 66 60 R-31 1 B Res 66 62 R-32 1 B Res 66 61 M-4 0 B Res 66 61 R-33 1 B Res 66 58 R-34 1 B Res 66 58 R-35 1 B Res 66 57 25 228th Street SW Corridor Improvements Project May 11, 2012 Table 6. Existing Modeled Traffic Noise Levels Land Use Receiver' Uses z Activity Land Represented Category3 Use Sound Level in Properties with Leq(dBA) Norse Levels 5 s Meeting NAC7 Criteria Existing R-36 1 B Res 66 57 R-37 1 B Res 66 55 POW -1 1 C POW 66 56 R-38 1 B Res 66 57 R-39 1 B Res 66 53 R -40/M-6 1 B Res 66 57 R-41 1 B Res 66 55 R-42 1 B Res 66 54 R-43 2 B Res 66 55 R-44 1 B Res 66 53 R-45 1 B Res 66 52 R-46 1 B Res 66 55 R-47 1 B Res 66 56 R-48 1 B Res 66 60 R-49 1 B Res 66 61 R-50 1 B Res 66 61 R-51 1 B Res 66 59 Notes: 1. 2. 3. 4. 5. 6. 7. All receivers are shown in Figures 8 and 9. Number of dwellings (or other uses) represented by each receiver FHWA land use activity category designation Land use: = Residential I POW = Place of Worship ( Com = Commercial/Office WSDOT traffic noise abatement criteria Calculated peak noise hour levels in dBA Leq from FHWA TNM version 2.5, with noise levels that meet or exceed the NAC in Bold -Reel typeface a, Number of uses with noise levels that meet or exceed the NAC. By definition, these are not considered "impacts" as impacts only occur for the Build scenario. This section discusses the future year 2035 No -Build and Build TNM analyses. The TNM inputs included projected year 2035 traffic volumes and speeds prepared for this project. The same fifty-six (56) noise modeling locations shown in Figures 8 and 9 and used to model the existing conditions were modeled for the No -Build Alternative peak hour traffic conditions. This section provides the noise modeling results for the No -Build conditions using traffic volumes projected for the year 2035 with no changes to any of the roadways in the project corridor. Table 7 summarizes the future 2035 No -Build traffic noise levels for these fifty-six receivers, and a discussion of the results follows the table. 26 228th Street SW Corridor Improvements Project May 11, 2012 Table 7. Future No -Build Modeled Traffic Noise Levels Receiver' Uses 2 Represented Land Use Activity Category3 Land Use4 Sound Level in Leq(dBA) 5 6 Criteria No -Build Properties with Noise Levels Meeting NAC' M-5 0 E Com 71 68 R-1 1 B Res 66 65 R-2 6 B Res 66 64 R -3/M-1 3 B Res 66 63 R-4 5 B Res 66 64 R-5 80 B Res 66 63 R-6 8 B Res 66 63 R-7 1 B Res 66 62 R-8 1 B Res 66 63 R-9 1 B Res 66 60 R-10 1 B Res 66 60 R-11 2 B Res 66 58 R-12 2 B Res 66 59 R-13 1 B Res 66 58 R -141M-2 3 B and C Res & Trail 66 62 R-15 4 B Res 66 57 R-16 3 B Res 66 58 R-17 4 B Res 66 60 R-18 2 B Res 66 61 R-19 1 B Res 66 64 R-20 1 B Res 66 65 R-21 2 B Res 66 61 R-22 4 B Res 66 56 R-23 4 B Res 66 57 R-24 4 B Res 66 56 R-25 2 B Res 66 60 R-26 1 B Res 66 63 R-27 1 B Res 66 64 R -28/M-3 9 B Res 66 67 9 R-29 6 B Res 66 fib 6 R-30 lower 10 B Res 66 59 R-30 (middle) 9 B Res 66 62 R-30 (upper) 9 B Res 66 63 R-31 1 B Res 66 65 R-32 1 B Res 66 64 M-4 0 B Res 66 R-33 1 B Res 66 fl60 R-34 1 B Res 66 R-35 1 B Res 66 R-36 1 B Res 66 59 R-37 1 B Res 66 57 27 228th Street SW Corridor Improvements Project May 11, 2012 Table 7. Future No -Build Modeled Traffic Noise Levels Land Use Sound Level in properties with Receiver' Uses 2 Activity Represented Land Use Leq(dBA) Noise Levels Category3 5 s Meeting NAC' Criteria No -wild POW -1 1 C POW 66 59 R-38 1 B Res 66 59 R-39 1 B Res 66 55 R -40/M-6 1 B Res 66 59 R-41 1 B Res 66 58 R-42 1 B Res 66 57 R-43 2 B Res 66 57 R-44 1 B Res 66 55 R-45 1 B Res 66 54 R-46 1 B Res 66 58 R-47 1 B Res 66 58 R-48 1 B Res 66 62 R-49 1 B Res 66 63 R-50 1 B Res 66 64 R-51 1 B Res 66 61 Notes: 1. All receivers are shown in Figures 8 and 9. 2. Number of dwellings (or other uses) represented by each receiver 3. FHWA land use activity category designation 4. Land use: Res = Residential I POW = Place of Worship I Com = Commercial/Office 5. WSDOT traffic noise abatement criteria s. Calculated peak noise hour levels in dBA Leq from FHWA TNM version 2.5, with noise levels that meet or exceed the NAC in Bold -teed typeface 7. Number of uses vAth noise levels that meet or exceed the NAC. By definition, these are not considered "impacts" as impacts only occur for the Build scenario. Under the 2035 No -Build Alternative, traffic noise levels are predicted to increase by up to 3 dB above existing peak -traffic hour conditions due to projected growth in traffic volumes. The No -Build modeled noise levels would range from 54 to 68 dBA Leq. Receivers R -28/M- 3 and R-29 would have traffic noise levels meeting or exceeding the NAC under the No - Build Alternative. The TNM modeling files are provided in Appendix G. x This section provides the noise modeling results for the 2035 Build Alternative. The same fifty-six (56) noise modeling locations shown in Figures 8 and 9 and used to model the existing conditions and No -Build Alternative were modeled for the Build Alternative peak - traffic hour traffic conditions. The TNM inputs included the planned extension of 228t1i Street Southwest, elimination of left turning traffic from SR 99 onto 76"' Avenue West, and the projected Build year traffic volumes and speeds. Table 8 summarizes the future 2035 Build Alternative traffic noise levels for these forty-seven receivers and lists the number of estimated noise impacts. A discussion of the results follows the table. 28 228th Street SW Corridor Improvements Project May 11, 2012 Table 8. Future Build Modeled Traffic Noise Levels Receiver' Uses s Represented Land Use Activity Cate o s 9 ry Land Use Sound Level in Leq(dBA) Noise Impacts' s s Criteria Build M-5 0 E Com 71 70 R-1 1 B Res 66 65 R-2 6 B Res 66 64 R -3/M-1 3 B Res 66 64 R-4 5 B Res 66 64 R-5 80 B Res 66 63 R-6 8 B Res 66 64 R-7 1 B Res 66 63 R-8 1 B Res 66 64 R-9 1 B Res 66 61 R-10 1 B Res 66 62 R-11 2 B Res 66 60 R-12 2 B Res 66 61 R-13 1 B Res 66 61 R -141M-2 3 B and C Res & Trail 66 65 R-15 4 B Res 66 59 R-16 3 B Res 66 60 R-17 4 B Res 66 61 R-18 2 B Res 66 62 R-19 1 B Res 66 65 R-20 1 B Res 66 65 R-21 2 B Res 66 62 R-22 4 B Res 66 57 R-23 4 B Res 66 56 R-24 4 B Res 66 55 R-25 2 B Res 66 59 R-26 1 B Res 66 61 R-27 1 B Res 66 63 R -28/M-3 9 B Res 66 65 R-29 6 B Res 66 64 R-30 lower 10 B Res 66 61 R-30 middle 9 B Res 66 63 R-30 (upper) 9 B Res 66 64 R-31 1 B Res 66 65 R-32 1 B Res 66 65 M-4 0 B Res 66 67 R-33 1 B Res 66 63 R-34 1 B Res 66 62 R-35 1 B Res 66 61 29 228th Street SW Corridor Improvements Project May 11, 2012 Table 8. Future Build Modeled Traffic Eloise Levels Uses Land use Receiver' Activity 3 Receiver' Rep re Category Use4 Sound Level in L,q(dBA) Noise Impacts' Criteria Build R-36 1 B Res 66 61 R-37 1 B Res 66 60 POW -1 1 C POW 66 62 R-38 1 B Res 66 62 R-39 1 B Res 66 58 R -40/M-6 1 B Res 66 60 R-41 1 B Res 66 59 R-42 1 B Res 66 60 R-43 2 B Res 66 60 R-44 1 B Res 66 56 R-45 1 B Res 66 55 R-46 1 B Res 66 60 R-47 1 B Res 66 60 R-48 1 B Res 66 65 R-49 1 B Res 66 65 R-50 1 B Res 66 65 R-51 1 B Res 66 63 Notes: 1. 2. 3. 4. 5. 6. 7. All receivers are shown in Figures 8 and 9. Number of dwellings (or other uses) represented by each receiver FHWA land use activity category designation Land use: = Residential I POW = Place of Worship i Com = Commercial/Office WSDOT traffic noise abatement criteria Calculated peak noise hour levels in dBA Leq from FHWA TNM version 2.5, with noise levels that meet or exceed the NAC in BoUl' od typeface Number of uses with noise levels that meet or exceed the NAC. The 2035 Build Alternative modeled noise levels would range from 55 to 70 dBA Leq. No receivers would have noise levels meeting or exceeding the NAC. Under the 2035 Build Alternative, traffic noise levels are predicted to increase by up to 6 dB above existing peak -traffic hour conditions due to the introduction of the new 228t1' Street Southwest extension and the projected growth in traffic volumes. The number of homes that would meet or exceed the NAC would remain at zero (0) under the Build Alternative. Under the 2035 Build Alternative, traffic noise levels are predicted to increase by up to 3 dB above 2035 No -Build peals -traffic hour conditions due to the introduction of the new 228t" Street Southwest extension and the projected changes in traffic volumes. In the future, traffic that is currently forced to take 76t" Avenue West in order to ultimately cross SR 99 will be able to use the new 228ti' Street Southwest extension under the Build Alternative. Hence, traffic noise levels at the townhome patios in the Ballinger Park townhome and apartment complex are expected to decrease by 2 dB under the Build Alternative when compared to the No -Build Alternative. As a result, there are no impacts at these homes under the Build Alternative, whereas the traffic noise levels at these homes are expected to meet or exceed the NAC under the No -Build Alternative. These homes are represented by receivers R- 30 228th Street SW Corridor Improvements Project May 11, 2012 28/M-3 and R-29. Similarly, other homes along this stretch of 76'1'Avenue West represented by receivers R-23 through R-27 are expected to experience a decrease in traffic noise levels of l to 2 dB under the Build Alternative when compared to the No -Build conditions. The TNM modeling files are provided in Appendix G. 6.3. Noise Levels Summary Table 9 provides a full summary of existing, 2035 No -Build Alternative, and 2035 Build Alternative noise levels for all receivers. Under the Build Alternative there would be no traffic noise impacts, including substantial increase traffic noise impacts (an increase of 10 dB or more above existing conditions). 31 228th Street SW Corridor Improvements Project May 11, 2012 N co J 1 0 -0 • N O O 9 UJ •� d' N N M co M co Cl) 'ci' M d' d' LO LO LO d' 'V' d' Cl) M co co Cl) N N <- ^4 h ® C. 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(0 (A N CO LD V �T (D O O 0) h O 0) Lo 0) 00 h- h LO IT co M (u (O (O (0 U) LO (0 C0 (0 (0 (0 (O (0 (0 LO LO LO LO L() LO LO LO LO LO LO LO LO � v J f!J (0 0 0 M I` LO O (0 d 0 N 0 — 0 r- (O M LO M LO I- LO ti Ln M LO 0 LO ti LO CO LO r` LO LO 0 °d” LO LA LO M LO N LO LO LO 0 LO w 0 � v (D (D (D (D (D (D (D (D (D f11 CMO (M0 (Mo (M0 ((0 (D (D (D CM9 CMo c00 c00 cM4 tM0 m m m m m m m m m m m m m m m v m m m m m m m m m m L 0 NU) d ® N c- — M (0 � 6) d r — r r z 5 4) M t-- 7c' d '9 N Q N �i M d' Ln M t` r CO M (0 N M d' M M r .� N N `� N y 7 M M M M i M i M M i �j M i M i O d' i V' i �T i d' i It i 'tl' i E i Q i CL 00 (v i � d d� i i C i � w�� LC d IY � D d m v N .o d Y C N 0 `L E 0 a 0 U v CO L 04 N N W, ® Z0 ca 0 16 <O _0 ui .,a LO -r —t -Lo 0 L. > sr 0 CL lco, 4® 2 0 C C; z 0 0 n Z Oa m > LO (0 LO (D LO (0 CO (D Lo LO 0 i®. ami (U 0) cr 0 2 (a ca UJ Co 0 -, C\j C*4 C) N cli 0 2 0 0 > > (14 Cl) 'T 0 0 (D eo (D Lo (D _j o (f) LO LO to !E vLLI 4) V. 0 (D U) E Eo cal r 0 0 z E to Co (D (0 0 mp �2 Qs z (D CO CO CO CO g �rz > 4') 00, E oc E U) w 0 E 0 c 10) 0 4) 0ID E a) x 4) c < 0 0 U) ON a) Z CO d);°= (a <E > E 0. 0) 0) 0 E u EZ 52 0- cl E ma) � E E , E- o a (60 -WO 0 0 Ls 0 U) 0 > a) 0 ®) 6 U) — — — — 0 z m co ca'a -0. '2-0 z (D C- 0) 6 di ,N 0 0 cou D.9 Lo- U o o o c cc 02 0) a) > E S .0 00 ,r 0')'T L,? 0 < z U- 0 0 Z 0 C) Wd E D� o- 0 � z :3 (n Li �' CA m -T vi 'D r- m m 10 . 2 z W, 7.1. Evaluation of Project Traffic Noise Abatement No impacts were identified and therefore no noise abatement was considered in connection with the proposed project. 7.2. Unavoidable Impacts There are no uses expected to have traffic noise impacts under the 2035 Build Alternative. 7.3. Construction Noise Analysis Construction noise levels for the proposed project improvements would result from normal construction activities. The City of Edmonds City Code Chapter 5.30 would apply to the construction of the proposed project. Daytime construction noise (during the hours of 7:00, a.m. to 6:00 p.m. on weekdays and 10:00 a.m. to 6:00 p.m. on Saturdays, excluding Federal Holidays) is exempt from the City Code. Noise levels for construction activities can be expected to range from 70 to 95 dBA at sites 50 feet from the activities. Table 12 lists equipment typically used for constructing this type of project, the activities for which the equipment would be used, and the corresponding maximum noise levels under normal use measured at 50 feet. 35 228th Street SW Corridor Improvements Project May 11, 2012 Table 12. Construction Equipment List, Use, and Reference Maximum Noise Levels Equipment Typical Expected Project Use a LmaxSourceb Air Compressor Used for pneumatic tools and general maintenance—all phases 70-76 1, 2, 3 Backhoe General construction and yard work 78-82 2,3 Concrete Pump Pumping concrete 78-82 2,3 Concrete Saw Concrete removal, utilities access 75-80 2,3 Crane Materials handling, removal, and replacement 78-84 2,3 Excavator General construction and materials handling 82-88 2,3 Haul Truck Materials handling, general hauling 86 2,3 Jackhammer Pavement removal 74-82 2,3 Loader General construction and materials handling 86 2,3 Paver Roadway paving 88 2 Power Plant General construction use, nighttime work 72 2,3 Pump General construction use, water removal 62 2,3 Pneumatic Tools Miscellaneous construction work 78-86 3 Service Truck Repair and maintenance of equipment 72 2,3 Tractor Trailer Material removal and delivery 86 3 Utility Truck General project work 72 2 Vibratory Equipment To shore up a hillside to prevent slides and soil compacting 82-88 2,3 Welder General project work 76 2,3 'Maximum noise level measured at a distance of 50 feet under normal operation. b Sources of noise levels presented: 1. Portland, Oregon light rail, 1-5 preservation, and Hawthorne Bridge construction projects. 2. Measured data from other projects in the Portland, Oregon area. 3. USDOT or other construction noise source. These noise levels, although temporary in nature, can be annoying. The following is a list of recommended noise mitigation measures that could be contained in the contract specifications: ® Require all engine -powered equipment to have mufflers that were installed according to the manufacturer's specifications. a Require all equipment to comply with pertinent EPA equipment noise standards. ® Limit jackhammers, concrete breakers, saws, and other forms of demolition to daytime hours of 8:00 a.m. to 5:00 p.m. on weekdays, with more stringent restrictions on weekends. ® Minimize noise by regular inspection and replacement of defective mufflers and parts that do not meet the manufacturer's specifications. 36 228th Street SW Corridor Improvements Project May 11, 2012 • Install temporary or portable acoustic barriers around stationary construction noise sources and along the sides of the temporary bridge structures, where feasible. • Where possible, schedule the construction of the residential noise barriers early in the project. In some jurisdictions, this maybe a requirement in order to get any noise variances. • Locate stationary construction equipment as far from nearby noise -sensitive properties as possible. • Shut off idling equipment. • Reschedule construction operations to avoid periods of noise annoyance identified in complaints. • Notify nearby residents whenever extremely noisy work would be occurring. • Use broadband back-up alarms or restrict the use of back-up beepers during evening and nighttime hours and use spotters. In all areas, Occupational Safety and Health Administration (OSHA) will require back-up warning devices and spotters for haul vehicles. • Use pile driving noise shroud and/or employ auguring techniques where possible to limit effects of pile driving. • Additional noise mitigation measures might be implemented as more details on the actual construction processes are identified. 7.4. Notification to Local Governments A copy of this report will be sent to the City of Edmonds, Snohomish County and the City of Mountlake Terrace. This report serves to inform local officials of the effects of the proposed project on local noise levels. The information contained within this report can assist the city in its planning process. It is recommended that the city use this information as a guide when developing future land use plans, zoning, and/or building code requirements. The use of this information may assist local government with future development plans and thereby result in development that is consistent with the noise environment. The information contained in this report should only be used as guidance. MM&A recommends that additional modeling be performed whenever the details of a proposed new development in the project corridor are more clearly understood. This will aid in determining whether such a development may require a more in-depth traffic noise analysis as part of the developer's permit process. 37 228th Street SW Corridor Improvements Project May 11, 2012 . . . • Date: 2/10/2012 Person Making Contact: Mike Kailas Person Contacted: Michael Clugston, Planner, City of Edmonds Planning Division In person Postal Mail Phone: Email: FAX 425-771-0220 clugston@ci.edmonds.wa.us o The City of Edmonds Planning Division was contacted to identify any permitted uses or use changes not revealed by analysis of the area. In a telephone conversation, Mr. Clugston informed us that there are no permitted projects in the project study area other than normal course home remodels and that there are no land use changes, rezones or comprehensive plan amendments currently permitted or under consideration. Mr. Clugston also indicated that certain unincorporated portions of the project study area are under the jurisdiction of Snohomish County and another portion of the study area is under the jurisdiction of the City of Mountlake Terrace How did you resolve the comments/concerns? ` o a s • •- o s Contact Snohomish County and the City of Mountlake Terrace to confirm that there are no permitted land use changes of which we are unaware. 38 228th Street SW Corridor Improvements Project May 11, 2012 Date: 2/21/2012 T_ Person Making Contact: Mike Kallas Person Contacted: Darryl Eastin, Principal Planner, Snohomish County Planning & Development Services Phone: Email: In person Postal Mail 425-338-3311 darryl.eastin@co.snohomish.wa.us FAX Ext -1068 Snohomish County Planning & Development Services was contacted to identify any permitted uses or use changes not revealed by analysis of the area. In a telephone conversation and in an e-mail, Mr. Eastin informed us that there are no permitted projects or any proposed or pending rezones or comprehensive plan land use changes in the project study area. How did you resolve the comments/concerns? oil 4 ... None 39 228th Street SW Corridor Improvements Project May 11, 2012 Date: 4/24/2012 Person Making Contact: Mike Kailas Person Contacted: Paula Schwartz, Planner, City of Mountlake Terrace In person Postal Mail Phone: Email: FAX 425-744-6280 The City of Mountlake Terrace planning office was contacted to identify any permitted uses or use changes not revealed by analysis of the area. In a telephone conversation, Ms. Schwartz informed us that there are no permitted projects or any proposed or pending rezones or comprehensive plan land use changes in the project study area. How did you resolve the comments/concerns? ' e • o • s- e a None 40 228th Street SW Corridor Improvements Project May 11, 2012 Appendix : Introduction to Acoustics Sound is defined as any pressure variation that the human ear can detect, from barely perceptible sounds to sound levels that can cause hearing damage. The magnitude of the variations of the air pressure from the static air pressure is a measure of the sound level. The number of cyclic pressure variations per second is the frequency of sound. When sounds are unpleasant, unwanted, or disturbingly loud, we tend to classify them as noise. Compared with the static air pressure, the audible sound pressure variations range from the threshold of hearing, a very small 20 µPa (20 x 10' Pascal), to 100 Pa, a level so loud it is referred to as the threshold of pain. Because the ratio between these numbers is more than a million to one, using Pascal to describe sound levels can be awkward. The "dB" measurement is a logarithmic conversion of air pressure level variations from Pascal to a unit of measure with a more convenient numbering system. This conversion not only allows for a more convenient scale, but is also a more accurate representation of how the human ear reacts to variations in air pressure. Measurements made using the decibel scale will be denoted dB. The smallest noise level change that can be detected by the human ear is approximately 3 dB. A doubling in the static air pressure amounts to a change of 6 dB, and an increase of 10 dB is roughly equivalent to a doubling in the perceived sound level. Under free -field conditions, where there are no reflections or additional attenuation, sound is known to decrease at a rate of 6 dB for each doubling of distance. This is commonly known as the inverse square law. For example, a sound level of 70 dB at a distance of 100 feet would decrease to 64 dB at 200 feet, or 58 dB at 400 feet. The mathematical definition of sound pressure level in dB is listed below. LP (sound pressure level). The sound pressure in dB is 20 times the log of the ratio of the measured pressure, p, to the static pressure, po, where po is 20 µPa. LP, = 20Log,o(p)dB (re 20pPa) PO In acoustic measurements where the primary concern is the effect on humans, the sound readings are sometimes compensated by an "A" -weighted filter. The A -weighted filter accounts for people's limited hearing response in the upper and lower frequency bands. Sound pressure level measurements made using the A -weighted filter are denoted dBA. For short-term and impulsive noises, such as surface blasting, a C -weighted filter is normally used. The C -weighted filter helps to account for the short time period and frequency of impulsive noises. 41 228th Street SW Corridor Improvements Project May 11, 2012 General Measurement Descriptors L,Q (equivalent continuous sound level). The constant sound level in dBA that, lasting for a time "T," would have produced the same energy in the same time period "T" as an actual A -weighted noise event. 2 L,,, 1 =20Log',o f ° 0( �o��t�J1 dt T MaxPeak (maximum A -weighted sound level). The greatest continuous sound level, in dBA, measured during the preset measurement period. (maximum A -weighted RMS sound level). The greatest RMS (root -mean square) sound level, in dBA, measured during the preset measurement period. L,,,,,, (minimum A -weighted RMS sound level). The lowest RMS (root -mean square) sound level, in dBA, measured during the preset measurement period. Community Noise Level Descriptors The following sound level descriptors are commonly used in community noise measurements: Ld" (day -night average sound level). A 24-hour equivalent continuous level in dBA where 10 dB is added to nighttime noise levels from the hours of 10:00 p.m. to 7:00 a.m. CNEL (community noise equivalent level). A 24-hour equivalent continuous level in dBA where 5 dBA is added to evening noise levels from 7:00 p.m. to 10:00 p.m. and 10 dBA is added to nighttime noise levels from 10:00 p.m. to 7:00 a.m. SEL (sound exposure level). That constant level in dBA that, lasting for one second, has the same amount of acoustic energy as a given A -weighted noise event lasting for a period of time T. This measurement is most commonly used for airport noise. Statistical Noise Level Descriptors Public response to sound depends greatly upon the range that the sound varies in a given environment. For example, people generally find a moderately high, constant sound level more tolerable than a quiet background level interrupted by high-level noise intrusions. In light of this subjective response, it is often useful to look at a statistical distribution of sound levels over a given time period. Such distributions identify the sound level exceeded and the percentage of time exceeded. Therefore, it allows for a more complete description of the range of sound levels during the given measurement period. The sound level descriptor LXX is defined as the sound level exceeded XX percent of the time. Some of the more common versions of this descriptor and their corresponding definitions are listed below: 42 228th Street SW Corridor Improvements Project May 11, 2012 • L01 The sound level is exceeded 1 percent of the time. This is a measure of the loudest sound levels during the measurement period. Example: During a 1 - hour measurement, an Lo, of 95 dBA means the sound level was at or above 95 dBA for 36 seconds. • L10 The sound level is exceeded 10 percent of the time. This is a measure of the louder sound levels during the measurement period. Example: During a 1 - hour measurement, an L10 of 85 dBA means the sound level was at or above 85 dBA for 6 minutes. • L50 The sound level is exceeded 50 percent of the time. This level corresponds to the median sound level. Example: During a 1 -hour measurement, an L50 of 67 dBA means the sound level was at or above 67 dBA for 30 minutes. • L90 The sound level is exceeded 90 percent of the time. This is a measure of the nominal background level. Example: During a 1 -hour measurement, an L90 of 50 dBA means the sound level was at or above 50 dBA for 54 minutes. • L99 The sound level is exceeded 99 percent of the time. This is the quietest or minimum level during the measurement period. Example: During a 1 -hour measurement, an L99 of 42 dBA means the sound level was at or above 42 dBA for 59 minutes and 24 seconds. Other commonly used LXX values include LZ 5, L8.3, and L25. These correspond to the 5-, 10-, and 15 -minute time levels for a 1 -hour measurement period, respectively. Sound Propagation Characteristics Several factors determine how sound levels reduce over distance. Under ideal conditions, a point noise source in free space will attenuate at a rate of 6 dB each time the distance from the source doubles (using the inverse square law). An ideal line source (such as constant flowing traffic on a busy highway) reduces at a rate of approximately 3 dB each time the distance doubles. Under real-life conditions however, interactions of the sound waves with the ground often results in attenuation that is slightly higher than the ideal reduction factors given above. Other factors that affect the attenuation of sound with distance include existing structures, topography, foliage, ground cover, and atmospheric conditions such as wind, temperature, and relative humidity. The following list provides some general information on the potential affects each of these factors may have on sound propagation. Existing Structures. Existing structures can have a substantial effect on noise levels in any given area. Structures can reduce noise by physically blocking the sound transmission and, under special circumstances, may cause an increase in noise levels if the sound is reflected off the structure and transmitted to a nearby receiver location. Measurements have shown that a single story house has the potential, through shielding, to reduce noise levels by as much as 10 dB or greater. The actual noise reduction will 43 228th Street SW Corridor Improvements Project May 11, 2012 depend greatly on the geometry of the noise source, receiver, and location of the structure. Increases in noise caused by reflection are normally 3 dB or less, which is the minimum change in noise levels that can be noticed by the human ear. Topography. Topography includes existing hills, berms, and other surface features between the noise source and receiver location. As with structures, topography has the potential to reduce or increase sound depending on the geometry of the area. Hills and berms when placed between the noise source and receiver can have a significant effect on noise levels. In many situations, berms are used as noise abatement by physically blocking the noise source from the receiver location. In some locations, however, the topography can result in an overall increase in sound levels by either reflecting or channeling the noise towards a sensitive receiver location. Foliage. Foliage, if dense, can provide slight reductions in noise levels. FHWA provides for up to a 5 dBA reduction in traffic noise for locations with at least 30 feet of dense evergreen foliage. Because foliage varies in the project area, no reduction for foliage will be used in the analysis. Ground Cover. The ground cover between the receiver and the noise source can have a significant effect on noise transmission. For example, sound will travel very well across reflective surfaces such as water and pavement, but can be attenuated when the ground cover is field grass, lawns, or even loose soil. During the environmental impact statement (EIS) phase of the project, detailed information related to sound transmission in the project area will be compiled through a combination of on-site monitoring, noise modeling, and published information. This information will be used during the final noise modeling to account for the varying ground conditions in the project area. Atmospheric Conditions. Atmospheric conditions that can have an effect on the transmission of noise include wind, temperature, humidity, and precipitation. Wind can increase sound levels if it is blowing from the noise source to the receiver. Conversely, it can reduce noise levels if blowing in the opposite direction. Noise propagation can also be significantly affected when the temperature gradient is such that an inversion is formed. Other atmospheric conditions, such as humidity and precipitation, are rarely severe enough to result in significant changes in noise level propagation. Typical Sound bevels Two figures are included as sound level reference material. Figure A-1 contains some common noise sources, their nominal maximum sound level in dBA, and the usual public response. The levels in this table are comparable to the Lr„a�' noise level descriptor. This table would be useful when comparing the loudest noise produced with other familiar noise sources a person may have experienced. 44 228th Street SW Corridor Improvements Project May 11, 2012 Figure A-1: Typical Maximum Sound Levels Jet aircraft takeoff from carrier (50 feet) 140 50 -horse power siren (100 feet) 130 Loud rock concert near stage, 120 Jet takeoff (200 feet) Float plane takeoff (100 feet) 110 Jet takeoff (2,000 feet) 100 Heavy truck or motorcycle (25 feet) 90 Garbage disposal, food blender (2 feet), 80 Pneumatic drill (50 feet) Vacuum cleaner (10 feet), 70 Passenger -car at 65 mph (25 feet) Large store air-conditioning unit (20 feet) 60 Light auto traffic (100 feet) 50 Bedroom or quiet living room 40 Bird calls Quiet library, soft whisper (15 feet) 30 High quality recording studio 20 Acoustic Test Chamber 10 0 Sources: Beranek (1988) and U.S. EPA (1971). Threshold of pain Uncomfortably loud Very loud Moderately loud Quiet Very quiet Just audible Threshold of hearing 64 times as loud 32 times as loud 16 times as loud 8 times as loud 4 times as loud 2 times as loud Reference loudness 1/2 as loud 1/4 as loud 1/8 as loud 1/16 as loud 45 228th Street SW Corridor Improvements Project May 11, 2012 46 228th Street SW Corridor Improvements Project May 11, 2012 Traffic Noise Monitoring Information Sheet Ic" -t, J -I - ;,'� �) � 2 � OA Project Name: 2- cl,o , Date: - ' - Site Number- BIA-c K Monitoring Location; LLL Meter., LA. �(-- �dl I —Itl"'..---- Time (12hr): IL4 ILA Meter Start Time:_LL�JL,'I.L_ End Time: '/,,'Y( _ Leq: 2.,6 -LLI- -L Weather Conditions: Traffic Counts: Roadway Name: --�Lt Cars MeclTrucks Hv yTrucks Speeds: 44 Roadway Name: S' Carsk,z MeclTrucks -7 HvyTrucks Speeds: � Roadway Name:, '.C 4I'll I 7 Cars,- MeclTrucks 3 HvyTrucks Speeds: Roadway Name: J'zccl Cars 2 ?-3 MeclTrucks --2-- HvyTrucks Speeds: Area Observations: J 4 U � �& ,( 16 fll� Site Sketch 7- 4, '4 6 MEMEMEEME Project Name: ZZ, Site Number: AA < A h., 1, , -C Date: Monitoring Location: Meter: , �if Time (12 hr): LI-L—PO — Meter Start Time:% End Tirne:" 3" L eq:-- Weather Conditions: 61 Traffic Counts: 7-01 Roadway Name: Cars Mecll'rucks. livyTrucks Speeds: 2 Roadway Name:. Cars MeclTrucks Hv�yTrucks Speeds: 2 Roadway Name: Cars MedTr"cks- Hvy'rrucks_ Speeds:— Roadway Name: Cars MeclTrucks livyTrucks _ Speeds: Area Observations: � �tf Trv,-K 5" G) orf J tA. 2`L6 33 Site Sketch 3, Traffic Noise Monitoring Information Sheet Project Name: d Date:. I/ Site Number: on: I/C Monitoring Location: Lr 60 Meter: C) I ( Time (12 hr): � �(S' End"rime: Jt' 6/ _ LZ JL46, Meter Start Tirne: f(L — __LVL' Z6, Leq: /,' a, Weather Conditions: 4L —21- 07THMMM Roadway Name: 1 f cars Roadway Name: Cars 4 A Roadway Narne: Z '30 Cars ti. Roadway Name:: Z 34 Cars MeclTrucks, 3 HvyTrucks Speeds:2 -5" MedTrUCI(5 d— HvyTrucks Speeds: MedTrucks HvyTrucks Speeds: MedTrUcks HvyTrucks Speeds: 2 -A,il 1 . ),+ Area Observations: �fllku��Lllll �7 Ll- -C-I I, �c, I (� I I 1� a, 1 i�cl -. V.3 " 4), -/,, Site Sketch PI C f ('o a 7- zq Traffic Noise Monitoring Information Sheet rC '/-- �-- 2d/,?- Site Number: Project Name: Date: Monitoring Location: x" Meter: Time (12 hr): 2,0"1" End -/ Meter Start Tim ---- -�- 0 —eL*t� Weather Conditions: lei 4, RZHRXr� Roadway Name: Cars 2,, MedTrucks livyTrucks Speeds: rl Roadway Name: Iz Cars /0 MedTrucks HvyTrucks Speeds: d. r— Roadway Name: 12- T2 It)6 Cars C2�-Ll MedTrucks Y I-IvyTrucks_ -3 Speeds: Roadway Name: J ;(" ? 0 Cars o2 Yd- MedTrucks HvyTrucks Speeds: Av., f1kenrunfinne- 2-- �/J_ tee"f-) (,, /trot.. 4�/ ?fA' IS e -J Site Sketch Traffic Noise Monitoring Information Sheet LL -(L: J Date: Site Number: Project Name: Meter: Monitoring Location: Meter Start Time:%�°End T1me:Z �,d� L e q: 6' Time (12 hr): Weather Conditions: �G(e- +-d r Traffic _(.outlts. v e— > I I 6 4(4- Roadway Name: Cars MedTrucks 1,,IvyTrucks Speeds: Name:- Cars MedTrticks WVTrucks Speeds: Roadway r Cars MedTrucks r;J- HvyTrucks Speeds: Roadway Name:= Cars MedTrucks HvyTrucks Speeds: Roadway Name: Area observations: -15R - Is - AID 39 Site Sketch ht (" (�,, Traffic Noise Monitoring Information Sheet Project Name: Date: siteNumber: Monitoring Location: (f6'� Meter:- dl(—k Time (12 hr):Y,' O'l IA Meter Start Tirne:/4 End Time: L Weather Conditions: .0 V14d C (� Y(w, Traffic Counts: Roadway Name: c > Cars MedTrucks HvyTrucks Speeds:, Roadway Name: Cars MedTrucks FivyTrucks Speeds: Roadway Name: Cars MedTrucks HvyTrucks Speeds: Roadway Name: Cars MedTrucks HvyTrucks Speeds: Area observations: %ed h oi 5-6 e Site Sketch /// / ^/�/\ �/ / / / � d.� { � 47 228th Street SW Corridor Improvements Project May 11, 2012 • • • •• • Washington State Department of Transportation. 2011 Traffic Noise Policy and Procedures. August 2011. U.S. Department of Transportation. FHWA Highway Traffic Noise Model User's Guide, Report No. FHWA-PD-96-009. Federal Highway Administration, Washington, D.C. January 1998. U.S. Department of Transportation. FHWA Highway Traffic Noise Model User's Guide, (Version 2.5 Addendum) Final Report. Federal Highway Administration, Washington, D.C. April 2004. U.S. Department of Transportation. Guidance Material for the Preparation of Environmental Documents. FHWA Technical Advisory T6640.8A. Federal Highway Administration, Washington, D.C. 1987. U.S. Department of Transportation. Highway Construction Noise: Measurement, Prediction and Mitigation. Federal Highway Administration, Washington, D.C. 1977. U.S. Department of Transportation. Sound Procedures for Measuring Highway Noise: Final Report. FHWA DP -45-1R. Federal Highway Administration, Washington, D.C. August 1981. 48 228th Street SW Corridor Improvements Project May 11, 2012 Frmm:Hauss Bertrand Sent: Wednesday, February 1S,JU12 1:53 PM To: Darrell Smith Cc: Stephanie Hansen Subject: RE: Air and Noise Modeling for 228th St. SW Corridor Improvement project / Infiltration System / ECS Several items: l. See response below inred. 2. Proceed with supplemental investigation / infiltration system unwest side ofHwy 99 3. Based on Monday's discussion, add Overlay in ECS. Based on the possible project additions, that seems to be the only significant item to include. Thanks and let me know if you have any qUestions. Bertrand ---Ohgina|Message--- Frorn:DaneUSmith Sent: Tuesday, February 14,2O12922AM To: Haums,Bertrand Cc: Stephanie Hansen Subject: Air and Noise Modeling for 228th St. SW Corridor Improvement project Our Ari and Noise folks need a little more traffic data. The biggest issue is that the no-bUild data was not provided. The turning movements at the intersection of 228th and 76th don't seem to match LIP. One (lO3Upostpnoceas)has7UOheadin8westto|-Sandtheothe/(2O35PMPeaNhas452 heading west tw|-5and the other 3SOturning tothe south? Below is the data set required by the WSDOI- policy and procedures manual -for noise and air 1. Existing (yeor?):see attachnoents(data frnm2O07and 2008) 2. Opening year (year?) with and without the project: considering Opeming year of 2014,applY296growth rate (consistent w/PSR[Regional Plan) tm2Q1Omodeling values (with Project) and tmZ007/2OO8va|ues(no bmi|d) l Future (J03OorID35)with and without the pnoject.: sameoommemtasabo*e 4. Heavy vehicle percentages (Just let us know if You do not have this data): only have this information forthe(2)attachments HDR is welcome to contact Michael Minor if they have any questions. 49 . 228th Street SW Corridor Improvements Project Map - 228th Street Improvements 228th Street Improvements Perteet 3/20/2012 Map Map - 228th Street Improvements 228th Street Improvements Perteet 3/20/2012 Map Appendix F: TNM Files on CD (Hardcopy only) 50 228th Street SW Corridor Improvements Project May 11, 2012