P & D CONSULTANTS - 2002 - Laserfiche WebLink

Home Browse Search

Grand Avenue Widening Project Environmental Impact Report Section 3.0 The front yards and the building faces of the single family residences on the west side of Grand Avenue between Fruit and Fourth Street are significantly impacted by traffic noise. The rear yards of these residences are sufficiently shielded from noise by the houses themselves. The residences east of Grand Avenue between Third and Fourth Streets are separated from the road by an existing vacant lot, and the increased distance of these units from Grand Avenue helps reduce their noise exposure. The rear yard of the residence on Fourth Street nearest to Grand Avenue is mitigated with a block wall 6.5 feet high, while the rear yard of the residence on Third Street nearest to Grand Avenue is mitigated with only a four -foot high wood fence. Existing Noise Contours Table 3.6-4 lists the 2001 ADT volumes for Grand Avenue and I-5, with the corresponding distances to the 60 dB, 65 dB and 70 dB Community Noise Equivalent Level (CNEL) contours. These values represent the distances from the centerline of the road to the contour values shown. The existing noise levels for Grand Avenue were and are shown on Figures 3.6-2 and 3.6-3 as lines, or contours, of equal noise level. Figure 3.6-2 shows the locations of the existing 60 dB, 65 dB and 70 dB CNEL contours for the segment of Grand Avenue between Seventeenth Street and Santa Ana Boulevard, and between Santa Ana Boulevard and Fourth Street. Figure 3.5-3 shows the locations of the existing 60 dB, 65 dB and 70 dB CNEL contours for the segment of Grand Avenue between Fourth and First Streets. These contours do not take into account the mitigating effect of any existing noise barriers or structures along the road. The noise sensitive land uses along Grand Avenue between Seventeenth Street and Santa Ana Boulevard are between 42 and 186 feet from the centerline of Grand Avenue. At these distances, the existing noise exposure levels in these areas range from 70.5 dB CNEL to 60.9 dB CNEL. The noise sensitive land uses between Santa Ana Boulevard and Fourth Street are between 57 and 205 feet from the centerline of Grand Avenue. At these distances, these areas are exposed to noise levels ranging from 69.5 dB CNEL to 61.1 dB CNEL. The noise sensitive land uses between Fourth and First Streets are between 74 and 171 feet from the centerline of Grand Avenue. At these distances, these areas are exposed to noise levels ranging from 67.5 dB CNEL to 62.1 dB CNEL. Railroad Noise The major commuter rail corridor connecting Santa Ana with Los Angeles and San Diego Counties is about 1,200 feet west of Grand Avenue. As a result, it was considered that this raih-oad may represent an existing source of significant levels of noise in this area. This line, which is owned and operated by the Southern California Regional Rail Authority (SORRA), currently accommodates Amtrak passenger trains conning from Los Angeles to San Diego, Metrolink commuter trains running from Los Angeles to Carlsbad, and freight trains running between San Diego and San Bernardino. F.WROJ-ENMGrand eirWew Text- Gran&Section 3 SpIRISection 3.6.doc Page 3.6-9