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<br />Spill light refers to light from a lighting installation that falls outside the boundaries of the property for which
<br />it is intended, and light trespass refers to spill light that, because of quantitative, directional, or type of light,
<br />causes annoyance, discomfort, or loss in visual performance and visibility. Light trespass is light cast where it is
<br />not wanted or needed, such as light from a streetlight or a floodlight that illuminates someone's bedroom at
<br />night, making it difficult to sleep.
<br />Glare refers to light that causes visual discomfort or disability or a loss of visual performance when a bright
<br />object appears against a darkbackground. Glare can be generated by building- exterior materials, surface paving
<br />materials, vehicles traveling or parked on roads and driveways, and stadium lights. Any highly reflective facade
<br />material is a concern because buildings can reflect bright sunrays.
<br />The City does not have an established threshold level for evaluating lighting impact. However, in urban
<br />environment with moderately high ambient lighting (i.e., LZ3 [lighting zone 3]), light trespass impacts could be
<br />considered significant if the vertical illuminance exceeds 0.8 fc. Lighting zones are assigned based on population
<br />figures from the 2000 Census and different lighting standards are set for each lighting zone (LZ). Areas can be
<br />designated LZl (dark), LZ2 (rural), or LZ3 (urban) (California Code of Regulations, Title 24, parts 1 and 6.
<br />For this analysis, a threshold of 0.8 fc, close to twilight condition as described in Table 1, is used.
<br />Although it is not possible to completely eliminate spill light, light trespass, and glare from the new light sources,
<br />as shown in Figure 13, 6tb Sheet Siz Photometric Plan 2, light levels along the edges of the park near the western
<br />boundary would not exceed 1.1 fc, which would be slightly brighter than under twilight condition (see Table 1).
<br />The light levels would decrease even more with distance. The lighting level at southern boundary would be
<br />slightly brighter at 1.4 fc, but the southern boundary is bordered by a row of parking garages, therefore, would
<br />not be affected by the increased light levels. Figure 14, Tali Vien, lighting Visual Simulation, illustrates computer
<br />generated view of the photometric plan shown in Figure 13. As shown, light trespass impacts of the proposed
<br />project would not be significant, as light levels at 1.1 fc would not adversely impact nighttime views of the area.
<br />Figure 15, lighting Visual Simulation, Bird's Eye Vien� from Soutbi est Career, and Figure 16, lighting Visual Simulation,
<br />Bird's Eye Vien from Northeast Comer, show bird's eye views of the 6u Street Site from the southwest and northeast
<br />corners of the site, respectively. These visual simulations were created by using IES files that contain
<br />measurements of light and light quantities. As shown, the proposed nighttime lighting would be focused at
<br />intended areas of the park without resulting in substantial spill light impact on the edges of the park The City
<br />is also proposing 8-foot to 4foot wall along the western boundary of the park, therefore, would further
<br />reducing spill light onto the adjacent residential uses
<br />As shown in Figure 13, 6th Sheet Site Photometric Plan 2, the maximum light levels along the western boundary
<br />would range from 0.2 fc to 1.1 fc. However, there is no east facing window on the 2-story residence to the west,
<br />and the one-story residential structure is approximately 10 feet from the western property line, and the lighting
<br />level at this structure would be 0.0 fc. Therefore, light trespass impacts at the nearest residential structure would
<br />not exceed 0.8 fc, and impacts would be considered less than significant.
<br />Although no specific lighting plan has been developed for the Raitt Street Site, similar type of nighttime lighting
<br />as the 6u Street Site would be provided. Since the nearest sensitive residence is approximately 10 feet from the
<br />park site, farther than the residential structures for the 6th Street Site, it is anticipated that the foot candle levels
<br />75C-68
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