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Light Spacing – Photometric Analysis For the preparation of the Feasibility Report, an assumed spacing of 75-feet between light fixtures was used to ensure a conservative cost estimate. The lighting layout in the Report included 80 shoebox style lights and 11 decorative lights, for a total of 91 fixtures. As noted previously, it has been determined that one of the decorative lights could be changed to a shoebox light. For this more in-depth review, a photometric analysis was performed using the illumination templates shown above to determine the required numbers of fixtures more precisely. The analysis was based on the standards of the Illuminating Engineering Society (IES) for trail lighting. The IES standards include a minimum recommended average amount of light as measured in foot- candles (fc), as well as a maximum ratio of the average illumination value to the minimum illumination value, to ensure sufficiently even lighting throughout the project. The first analysis was performed using a pole spacing of 80-feet, which was the spacing used in the construction of trail segments 9 & 10. The analysis determined that the lighting still met the IES standards at this pole spacing. Using this spacing, the photometric analysis found that 85 total fixtures would be needed to illuminate the pathway. Ten of these would be decorative fixtures at intersections, with the other 75 being shoebox fixtures. A layout of Analysis 1 is shown in Attachment B to this Staff Report. The results of the first analysis indicated that the poles may be able to be spaced even further apart while still meeting the recommended standard. Therefore a second analysis was performed using 100-foot spacing between poles. This analysis found that the standards would be met, and that the total number of lighting fixtures could be reduced to 72 – the 10 decorative fixtures and 62 shoebox fixtures. A layout of Analysis 2 is shown in Attachment C. A third analysis was performed using 110-foot spacing between poles. This analysis found that the 110-foot spacing would meet the IES recommended value for average light level in foot-candles. However, the maximum ratio of the average illumination value to the minimum illumination value was 15:1, which exceeds the IES recommended 10:1 maximum. Therefore, the 110-foot spacing would not provide uniform lighting along the trail and is not a suitable option for this project. The lighting levels and fixture quantities for the options described above are summarized in the table on the following page.