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Maehl to Mann/Street LightingIAhlDW012K� . June 7, 2007 93 & Church, LLC Attn: Howard Mann 100 Hathaway Lane Kalispell, MT 59901 Re: Street Lighting — Silverbrook Estates Dear Mr. Mann: In an earlier letter to Frank Castles, we had requested a deviation to the city standards on street lighting requirements for the Silverbrook Estates project. The City of Kalispell Public Works Department currently has a requirement of minimum maintained illumination of 0.3 foot-candles and a uniformity ratio that shall not exceed 6:1, throughout the sidewalks along all streets in the city. What we had proposed to the City was to meet these requirements on Silverbrook Drive, but on the side streets, have a light standard at each intersection as well as a light that is a maximum of 750 feet from each intersection. This condition would create more of a dark sky while providing adequate lighting for pedestrians to walk "to the light" along Silverbrook Estates' sidewalks. This approach would eliminate a condition that we strongly feel will result in excessive lighting in a suburban setting. It is our understanding that the City did not approve this request, and is requiring that all streets within the subdivision meet the current City lighting requirements. We recently took some light readings at other subdivisions within Kalispell to see how the lighting levels within these subdivisions compare with the current standards. Following are the light levels we measured: Glacier Commons: ® Directly under a lighting fixture —1.50 foot candles ® Across the street from the fixture — 0.07 foot candles ® Darkest spot between the fixtures — 0.00 foot candles Granary Ridge: • Directly under a lighting fixture — 7.41 foot candles ® Across the street from the fixture — 0.55 foot candles ® Darkest spot between the fixtures — 0.14 foot candles c:\documents and settings\ownehlocal settings\temporary internet files\content.ie5\096vg923\mann letter[1].doc Buffalo Stage: ® Directly under a lighting fixture — 0.50 foot candles • Across the street from the fixture — 0.12 foot candles ® Darkest spot between the fixtures — 0.01 foot candles As can be seen by these measurements, none of these subdivisions would meet the current City requirement of minimum maintained illumination of 0.3 foot-candles. Based on the minimum measured foot candles, it does not appear that the City required uniformity ratio of 6:1 could be achieved either. Our goal is to provide adequate lighting for pedestrian safety, but not obtrusive to the homeowners. We feel it would be worthwhile to meet with the City again to see if a compromise could be reached regarding this issue. c:\documents and settings\ownerUocal settings\temporary internet files\content.ie5\096vg923\mann_letteglj.doc -2- Street Liahtinci Ordinances (local residential Grand Junction, CO http:/Avww.ci.gran(*d.co. us/CityDeptWebPages/PublicWork&AndUtil itiesfTransportationEngineeringrrEFilesThatLINI(intoD W StoreHere/TEDS/chap8R. pdf Table 8-1 Average Maintained Illuminance (Foot Candles) on Public Streets Local Residential Streets * "On local residential streets, a standard light shall be located at each street intersection, at or near the throat of each cul-de-sac, and at a maximum spacing of 250 feet measured along the centerline of the roadway. Additional lights may be required on horizontal curves at other locations." Portland, OR (page 1 of each) http:/Avww.portiandonline.com/shared/cftnfimage.cfm?id=36176 City of Portland Street Lighting Standards Local Service >_0.006 Lee FL 55 Ave Min (Overall) <10 Max Min (Overall) None Max Min (Longitudinal) hftp://www,portlandonline.com/auditor/index.cfm?a=dgbhe&c=dbbie 1. The adopted Street Lighting Standards also currently recommends an average, horizontal lighting standard (Eh Ave) of > .2 footcandles for all Local Service (residential) streets, plus a uniformity ratio of < 6 (average to minimum footcandles) and the ratio of < 20 (maximum to minimum footcandles). 2. A recent study of street light spacing and distribution ratios by Lighting Systems Management for the City of Portland Bureau of Street Lighting, determined that the Eh Ave. standard or > .2 is acceptable with lights spaced from 250 feet to 295 feet; however, the < 6 and/or < 20 light distribution ratios on Local Service streets, where light spacing is 295 feet or more, cannot be obtained. Therefore, the study recommends these latter ratios be deleted from the Street Lighting Standards. Bozeman, MIT (page 42-16) http:/Avww.bozeman.neVbozeman/Chapter 42_March_24 2007_1693.pdf Table 42-2 Local Street Lights (page 42-16) 1 Street lights are only required at intersections on local streets. Tempe, AZ (page 5) http:/ vww.tempe.goviengineering/standard_details/mag_4-8.pdf T-100.4 Subdivision Lighting (page 5) "All intersections of residential subdivisions shall have street lighting. Street lighting shall be located on public road rights - of -way, at the side lot line of the property where possible." Vancouver, WA http:/Avww.cityofvancouver. us/TrafficSafety.asp?menuid=10465&submenulD=19947&itemlD=1834D "The recommended "average luminance level" ranges from 0.3 Candelas per Square Meter for local, residential streets to 1.2 Candelas per Square Meter for Major Arterials in a Commercial area." Naperville, IL (page 6) http:/Avww.naperville. i I. uslemplibrary/Se,ction4. p& Table 4.5.1 Performance Standards for Street Lighting Local Streets Max FC 5 3.5 Min FC N/A Ave FC �: 0.4 Ave/Min Ratio N/A Bulb Type HIPS Wattage 100