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Grand Avenue Widening Project Environmental Impact Report Section 3.0 As described earlier in Section 1.0 (Project Description and Project Objectives), Alternatives 1 and 2 will provide the same number of through travel lanes on the project segment of Grand Avenue. Alternative 1 proposes to widen Grand Avenue to a right-of-way width of 100 feet and Alternative 2 proposes to widen Grand Avenue to a right-of-way width of 120 feet. The major difference between these two Alternatives is the addition of a five-foot wide, continuous bicycle lane in Alternative 2. The project traffic volumes and the width of the traveled portion of the road surface would be the same for both Alternatives. Therefore, the noise analysis of the with project scenario assesses the potential noise impacts of both Alternatives 1 and 2. The projected 2020 traffic volumes for this analysis are from the Traffic Study (January 2002). Table 3.6-6 lists the projected traffic volumes on the project segment of Grand Avenue and the corresponding distances to the 60 dB, 65 dB and 70 dB CNEL contours under the No Project Alternative. Table 3.6-7 lists the projected traffic volumes and corresponding distances to various noise contours for the with project scenario. The traffic mix in terms of truck percentages and time distributions for the project segment of Grand Avenue for 2020 were assumed to be the same as for existing conditions. The values in Tables 3.6-6 and 3.6-7 represent the distances from the centerline of the project segment of Grand Avenue, under the No Project and the widening alternatives, to the 60 dB, 65 dB and 70 dB noise contours. Figure 3.6-7 shows the locations of the 60 dB, 65 dB and 70 dB CNEL contours for the Future No Project case between Seventeenth Street and Santa Ana Boulevard, and between Santa Ana Boulevard and Fourth Street. Figure 3.6-8 shows the locations of the 60 dB, 65 dB and 70 dB CNEL contours for the Future No Project case between Fourth and First Streets. Figure 3.6-9 shows the locations of the Future With Project case 60 dB, 65 dB and 70 dB CNEL contours between Seventeenth Street and Santa Ana Boulevard, and between Santa Ana Boulevard and Fourth Street. Figure 3.6-10 shows the locations of the Future With Project case 60 dB, 65 dB and 70 dB CNEL contours between Fourth and First Streets. These values do not take into consideration the effect of any noise barriers, topography or intervening buildings which would alter these noise level projections. To determine the change in noise levels associated with the proposed widening of Grand Avenue, a comparison was made between the 2020 with and without project noise levels. Table 3.6-8 lists the existing and 2020 noise levels in dB CNEL at fifty feet from the centerline of the project segment of Grand Avenue, for existing conditions, and the 2020 No Project and 2020 with project scenarios. Table 3.6-8 shows the difference in noise levels as.a result of future growth and the difference in noise levels as a result of the proposed widening of the project segment of Grand Avenue alone. The project related noise impact is the difference between the 2020 with project values and the 2020 No Project Alternative noise levels. The results in Table 3.6-8 indicate there will be an increase in noise levels along the project segment of Grand Avenue due to normal growth through 2020. This growth will result in a projected increase in noise levels ranging from a 0.8 dB increase between Seventeenth Street and First Street. An increase in noise of 0.8 dB CNEL is not considered significant. F:IPROJ-ENMGrand eirlNew Text- GrandlSection 3 SplitlSection 3.6.doc Page 3.6-24