Agenda - Planning Commission - 11/09/1995

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OCTOBER 1995 AMERICAN PLANNING ASSOCIATION Shedding Light on the Urban Landscape /~ lumirmlre ~ ~~ff / lumP.ire ,, , , < NO C~OFF LUM,~ LU~N~RE ~ ~SS ~ "' C~OFF 90° C~OFF LUSTRE Th~ amount of cutoff~rovided in a iight~ture pr°teets against excessive g~re and light treSP~,: A cutoff luminaire (~ghO enst{res that no light ~ ~mi~ed above a horizontal Bne para~el to the ~ound. A luminaire with a eutoffofless than 9~ d~es (mi~) compleu0 shie~ the light xou,=e~om an obs~ver~ve~et above the W'ound at the point w~)ere the cutoff angle intersects the ~ound, ' Exterior lighting h~ seldom~been a prioriw for planners, produce light by passing an electric current through a g~. Ve~ who o~en =e not ~owle~g~ble about the subject. This few communities in the United States still use incandescent =pect of~e urb~ enviro0ment more o~en h~ been lamps for street lighting because, although they produce a soft, h~ed by engineers, public wor~ o~ci~s, ~d li~ting trade ~d white, attractive light, they are both costly and w~teful of utiliw company repr~entativ=. ~ecisiom concerning lighting ~m ener~. One communiw that does~Kennebunkport, Maine~ and d~ign o~en have been made,by ~ose public o~ci~s who pay is discussed below. the bills and mint fa~ the grim r~iw of~st con~nment. HID lamps include mercu~ vapor, high-pr~sure sodium But all that is changing. Several factors play a part in what (HPS), low-pr~sure sodium (LPS), and metal halide. Mercu~ seems to be the general ' ' ~' pubhc ~ increased inter~t in the visual vapor lighting produc= a harsh yellow light that is aestheti~lly environment. These include a ~eightened awareness of the unappealing but cheap to maintain. It was used widely in the aesthetic value of their communities, consciousness of United States until the introduction of sodium lighting in the environmental pollution, and i~cre~ed fear of crime. These 1970s. HPS h~ now become the nation's main source of concerns have complicated the ~ic purpose of light--to exterior lighting. illuminate and provide securi~and ~n create situations in Bemuse of its strong illumination and because it distorts which these purposes are at od~ with each other, color less than LPS, law enforcement officials prefer high- Most communities have to re~gni~ and deal with the pr~sure sodium. For them, identification of suspects is crucial. problem of glare. Light tresp~s ~om one land use to another Citizens have also come to prefer it as their fear of street crime needs to be regulated. R=identi~ neighborhoods must be intensifies. Some lighting professionals, however, feel that the protected from glare from parkin~ lots, sports facilities, and other recreational events like outdoor obncerts. Streets need to be lit well enough to give residents a feelin~of securit-y. The lighting must also be attractive enough to makd..' commercial and recreational facilities inviting and create a lively and prosperous setting. This issue of ZoningNews reports on communities that have produced inventive lightiqg plafis and ordinances and have taken a holistic approach, addreising lighting in all areas of the community and involving a cro~-section of citizens in the process. It also loo'ks at some goqd regulations and the measures they take to control glare, proteQt privacy, and promote safety. Lighting Glossary Exterior lighting types fall into two main categories-- incandescent lamps (the type us{d to illuminate most homes) and the more prevalent high-intinsity discharge (HID) lamps. Incandescent lamps produce liglit by heating a filament to high temperatures through an electriC'current while HID lamps safety feature has been overrated and that the glare produced by HPS is a hazard in itself. Metal halide produces a warm white light that is akin to incandescent lighting, is aesthetically pleasing, and produces excellent color rendition. But it suffers from high maintenance costs owing m a lower lamp life. "Group relamping rather than spot relamping is the answer to this problem," says Nancy Clanton, president of Clanton Engineering in Boulder, Colorado. Clanton says most of the costs of replacing lamps are labor costs and that replacing whole areas of lamps at one time regardless of whether or not all are burned out is a cost-efficient maintenance scheme. Lighting Plans Kennebunkport, Maine. This town has "one of the two best lighting ordinances in the United States," says Tony Dater, a consultant in Biddeford, Maine. His other choice: Tucson, Arizona. First developed in 1970 by a committee of citizens and planners chaired by city engineer Peter Talmadge, the