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OCTA I Santa Ana/Garden Grove Fixed Guideway Project <br />FNNoise and Vibration Technical Addendum <br />No Impact: A proposed project is considered to have no noise impact since, on average, the introduction of <br />the project will result in an insignificant increase in the number of people highly annoyed by the new noise. <br />Moderate Impact: The change in the cumulative noise level is noticeable to most people, but may not be <br />sufficient to cause strong, adverse reactions from the community. <br />Severe Impact: A significant percentage of people would be highly annoyed by the new noise. <br />Noise Evaluation of Proposed Minor Project Modifications <br />DECREASE IN SPEED <br />Reducing the maximum speed within the PE ROW from 45 mph to 44 mph would have no effect <br />on the streetcar operation, audible warning, crossing, or operations and maintenance (O&M) <br />noise levels. <br />CENTERLINE RE -ALIGNMENT (ALIGNMENT SHIFT) <br />This proposed modification would shift the railroad alignment within the PE ROW. Table D, <br />Comparison of the 30 Percent Design and 60 Percent Design Alignment Noise Levels, lists the <br />distances from the modeled receivers to the 30% design alignment and the distances to the <br />currently proposed 60% design alignment. Table D also lists the streetcar operation noise levels <br />associated with the 30% and 60% design streetcar alignments. <br />Table D: Comparison of the 30 Percent Design and 60 Percent Design Alignment Noise <br />Levels (d BA) <br />Receiver <br />Land <br />Use <br />Cat. <br />30% Design <br />Distance to Track <br />Centerline (ft) <br />60% Design <br />Distance to Track <br />Centerline (ft) <br />30% Design <br />Streetcar <br />Operations <br />Noise Level <br />60% Design <br />Streetcar <br />Operations <br />Noise Level <br />Change in <br />Streetcar <br />Operations <br />Noise Level <br />R1 <br />2 <br />89 <br />89 <br />56 <br />56 <br />0 <br />R2 <br />2 <br />90 <br />95 <br />52 <br />51 <br />-1 <br />R3 <br />2 <br />92 <br />91 <br />52 <br />52 <br />0 <br />R4 <br />2 <br />92 <br />89 <br />52 <br />52 <br />0 <br />R5 <br />2 <br />55 <br />49 <br />54 <br />54 <br />0 <br />R6 <br />2 <br />49 <br />49 <br />59 <br />59 <br />0 <br />R7 <br />2 <br />37 <br />37 <br />64 <br />64 <br />0 <br />R8 <br />3 <br />92 <br />85 <br />53 <br />53 <br />0 <br />R9 <br />3 <br />401 <br />370 <br />50 <br />50 <br />0 <br />R11 <br />3 <br />134 <br />115 <br />51 <br />52 <br />+1 <br />R10 <br />2 <br />55 <br />66 <br />58 <br />57 <br />-1 <br />R12 <br />2 <br />49 <br />58 <br />59 <br />58 <br />-1 <br />R13 <br />2 <br />60 <br />78 <br />58 <br />57 <br />-1 <br />R15 <br />2 <br />N/A <br />N/A <br />N/A <br />N/A <br />N/A <br />R14 <br />2 <br />110 <br />97 <br />55 <br />56 <br />+1 <br />Source: HDR (June 2016 and February 2017). <br />Table E lists the noise levels associated with the vehicle audible warning, and the distances <br />from the modeled receivers to the 30% and 60% design streetcar alignments. <br />7 <br />