2014-069 - Final Environmental Impact Report No. 2014-01

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HARBOR BLVD. MIXED USE TRANSIT CORRIDOR PLAN FINAL FIR CITY OF SANTA ANA 5. Environmental Analysis NOISE Summary of Traffic Noise Impacts As shown on the table above, the highest noise level increase would be at the segment of Edinger Avenue from Fairview Street to Harbor Boulevard noise increase of 1.3 over existing conditions and a project contribution of 0.7 dBA. These increases would be below the thresholds discussed above; as a result, traffic- related project noise impacts would be less than significant. Impact 5.9 -2 Noise levels at proposed residential areas would be above the 45 dBA CNEL interior noise standards. [Thresholds N -1 and N -31 Impact Analysis: The Harbor Corridor Plan proposes to gradually convert existing commercial and RV /auto - related land uses to allow for approximately 4,600 residential units and 2 million square feet of commercial space in the plan area. Land use changes under the Harbor Corridor Plan would involve replacing the North Harbor Specific Plan's (NHSP) zoning districts with four Harbor Corridor Plan zones, as described in Section 3, Project Description. Mixed use opportunities (commercial /residential would be introduced along the corridor. The transit node and corridor areas would include high- density and medium density housing primarily on areas along Harbor Boulevard. Neighborhood transitional zoning along 1st Street and 5th Street would allow for low- to medium - density residential development. As shown on Tables 5.9 -7 and 5.9 -8 above, these areas would be exposed to exterior noise levels at the edge of the right- of-way on Harbor Boulevard ranging from 65.5 to 71.3 dBA CNEL. The City's adopted noise standards (shown in Table 5.9 -3) for residential areas, parks, and outdoor living areas such as private yards, balconies, and park picnic areas shall not exceed 65 dBA CNEL. Without mitigation, outdoor living areas at residential uses and parks would have the potential to be exposed to noise levels above the 65 dBA CNEL exterior noise standard. This would be a significant impact. For noise - sensitive residential uses, habitable rooms including bedrooms, living rooms, and dining rooms shall not exceed the 45 dBA CNEL interior noise standard. Since standard construction materials and methods provide an exterior -to- interior noise reduction of approximately 25 dBA for new residential structures, the expected interior noise level at rooms facing the major roads within the Harbor Corridor Plan would be approximately 47 dBA CNEL (72 dBA CNEL exterior minus 25 dB for insulation reduction. With standard construction, the interior noise levels at habitable homes could exceed the 45 dBA CNEL noise standard. This would be a significant impact. Impact 5.9 -3: Noise from the operation of commercial uses could cause the noise level at the property line of any adjacent residential property to exceed the City of Santa Ana noise standards. [Thresholds N -1 and N -3] Impact Analysis: Adoption of the Harbor Corridor Plan would allow for approximately 2 million square feet of commercial space in the plan area. Retail uses would accommodate retail, restaurant, entertainment, and other pedestrian- oriented uses at street level, with offices and flats above in the mixed use building types. The City of Santa Ana's Municipal Code includes noise standards for residential properties, summarized in Table 5.9 -4. October 2014 Page 5.9 -13