AgdaPkt 2015-09-21 Joint Special SAF PAF

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Red Morton Community Park Sports Lighting Initial Study City of Redwood City 57 June 2015 New sports lighting would be installed at Mitchell Field, located in the northern portion of the park. While the nature of activities at Mitchell Field would not change under the proposed project, the hours of operation would continue until 10:30 PM up to seven days per week. The noise study determined that the existing noise environment at Mitchell Field is approximately 58 dBA CNEL. The measured noise levels during the hours of existing activities on Mitchell Field were used to estimate the levels expected during the future extended hours from dusk to 10:30 PM. Under the proposed project, the future noise environment would potentially increase to 60 dBA CNEL. This would not exceed the City’s General Plan conditionally acceptable threshold of 60 dBA CNEL at residential land uses. Compared to the existing ambient conditions, which ranged from 56 to 60 dBA CNEL in the vicinity of Mitchell Field, there would potentially be up to a four dBA increase in noise levels after dusk attributable to activities occurring on the lighted field. This increase would not exceed the City’s Municipal Code Section 24.20A regulation of an increase of six dBA for excessive and unreasonable noises. In addition, the increase in noise would cease at 10:30 PM. This would be a less than significant impact. Traffic Noise Typically, a significant permanent traffic noise increase would occur if the project would increase noise levels at noise-sensitive receptors by three dBA CNEL or greater where ambient noise levels exceed the normally acceptable noise level standard. Where ambient noise levels are at or below the normally acceptable noise level standard, noise level increases of five dBA CNEL or greater would be considered significant. Ambient noise levels at the nearest single-family residences along Roosevelt Avenue are currently 60 dBA CNEL, which exceeds the 55 dBA CNEL normally acceptable standard established in the City’s General Plan. Therefore, a significant impact would occur if the noise levels increased by three dBA CNEL or greater. Since the ambient noise levels along Myrtle Street and Madison Avenue range from 57 to 58 dBA CNEL, a three dBA CNEL or greater increase along these roadways would also constitute a significant impact. Along Valota Road, ambient levels are approximately 51 dBA CNEL. Therefore, a significant impact would occur along Valota Road if the noise environment increased by five dBA CNEL or greater. Since the only operational difference between existing conditions and project conditions would be the extended hours at Mitchell Field from dusk until 10:30 PM, the traffic report prepared by Hexagon Transportation Consultants, Inc. focused the study on traffic along the surrounding roadways between the hours of 4:00 PM and 11:00 PM. It was determined that a total increase of 55 trips per hour would occur with the extended hours of operation at Mitchell Field. According to the traffic report, no single street would be expected to receive all the additional trips because the trips approaching and leaving the park do not all use the same route. However, in calculating the worst-case scenario for noise, an increase of 55 trips per hour was used along each roadway. A noise increase of less than one dBA was determined for single-family residences along Roosevelt Avenue and Valota Road. The noise increase at noise-sensitive receptors along Madison Avenue was less than two dBA, and the noise increase along Myrtle Street was calculated to be less than three dBA. Therefore, as described above, traffic generated by the proposed project would not result in a significant noise impact. 8.A. - Page 74