06 16 20 PWA_02_02 Exh2 - IS-MND

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L w FAIRVIEw BRIDGE REPLACEMENT AND STREET IMPROVEMENTS INITIAL STUDY/MITIGATED NEGATIVE DECLARATION `J' (9TH STREET TO 16TH STREET) PROJECT MAY 2020 SANTA ANAL CALIFORNIA 3.13.1.1 Existing Noise -Sensitive Land Uses in the Project Area Noise -sensitive receptors include residences, schools, hospitals, and similar uses that are sensitive to noise. Sensitivity to noise increases during the evening and at night. Noise -sensitive land uses located in the Project area are single-family and multifamily residences located adjacent to Fairview Street. Other non -noise -sensitive land uses located within the Project area include a medical office, a passive park (Fairview Triangle), a multiuse trail, vacant land, and commercial and light industrial uses. Recreational land uses in the Project area are not considered noise sensitive because there are no outdoor active -use areas where people would be regularly exposed to noise for an extended period of time. 3.13.1.2 Ambient Noise Levels Short-term (20-minute) and long-term (24-hour) ambient noise measurements were conducted to document the existing noise environment in the Project vicinity. In total, 15 short-term measurement locations were conducted on April 17, 2018 and May 10, 2018, using Larson Davis Models 831, 824, and 820 Type 1 sound level meters. Table 3.13.13 shows the results of these measurements and the descriptions of the physical locations of the noise monitoring sites. As shown in Table 3.13.13, daytime noise levels in the Project vicinity range from 50.0 to 74.0 A -weighted decibels equivalent continuous sound level (dBA LED). Two long-term measurement sites were selected to capture the diurnal traffic noise level pattern in the Project area. Long-term ambient noise monitoring was conducted using one dosimeter at two representative locations in the Project area. The long-term noise level measurement at LT-1 was performed from 9:00 a.m. on Tuesday, April 17, 2018, to 9:00 a.m. on Wednesday, April 18, 2018, at a single-family residence at 1008 King Street. The noise levels ranged from 62 to 73 dBA Leq. The long-term noise level measurement at LT-2 was performed from 2:00 p.m. on Wednesday, April 18, 2018, to 2:00 p.m. on Thursday, April 19, 2018, at a single-family residence at 2505 West 16th Street. The noise levels ranged from 57 to 67 dBA LED. Receptor locations are shown on Figure 5. 3.13.1.3 Existing Traffic Noise The primary existing noise sources in the Project area are transportation facilities, which include Fairview Street. Traffic noise levels were predicted using the FHWA's Traffic Noise Model Version 2.5 (TNM 2.5).48 Key inputs to TNM 2.5 were the locations of roadways, traffic mix, vehicle speeds, shielding features (e.g., topography and buildings), noise barriers, ground type, and receptors. The existing a.m. peak -hour traffic volumes obtained from the TIA49 or the worst -case traffic operations (prior to speed degradation), whichever were lower, were coded into TNM 2.5 with existing roadway conditions. The a.m. peak -hour traffic volumes were selected over the p.m. peak -hour traffic volumes because the long-term (24-hour) noise level measurements indicate that the peak noise hour occurs during this period. A total of 92 receptor locations were modeled to represent land uses in the Project area as shown in Figure 5. Table 13.1 in Appendix B of the NSR (Appendix A of this IS/MND) provides the results of the existing traffic noise modeling. 48 United States Federal Highway Administration. 2004. Traffic Noise Model (TNM) Version 2.5. April. 49 LSA Associates, Inc. 2018b. Traffic Impact Analysis. June. 3-72 R:\WKE1702\ISMND\Final ISMND\Fairview Street Bridge Final ISMND.docx (05/26/20)