[HISTORY: Adopted by the Annual Town Meeting of the Town of Nantucket 4-14-2005, Art. 52, approved 10-18-2005. Amendments noted where applicable.]
Zoning — See Ch. 139.
Good outdoor lighting at night benefits everyone. It increases safety, enhances the Town's nighttime character, and helps provide security. New lighting technologies have produced lights that are extremely powerful, and these types of lights may be improperly installed so that they create problems of excessive glare, light trespass, and higher energy use. Excessive glare can be annoying and may cause safety problems. Light trespass reduces everyone's privacy, and higher energy use results in increased costs for everyone. Light exposure to ecosystems is known to interfere with the circadian rhythms of plants and animals.
There is a need for a lighting bylaw that recognizes the benefits of outdoor lighting and provides clear guidelines for its installation so as to help maintain and complement the Town's character. Appropriately regulated, and properly installed, outdoor lighting will contribute to the safety and welfare of the residents of the Town.
The primary purpose of this chapter is intended to reduce the problems created by improperly designed and installed outdoor lighting. It is intended to eliminate problems of glare, minimize light trespass, and help reduce the energy and financial costs of outdoor lighting. It establishes regulations that limit the wattages and lumens of outdoor lights, the direction of lighting and the area that certain kinds of outdoor lighting fixtures can illuminate.
The secondary purpose of this chapter is to preserve the rural nature of the countryside, enhance nighttime enjoyment of property, to protect property values by controlling light trespass, and to enhance the enjoyment of the night sky.
All lighting standards in this chapter are applicable to all lighting and no lighting shall be installed or continued that violates the standards of this chapter.
As used in this chapter, the following terms shall have the meanings indicated:
- EVENT LIGHTING
- Any lighting used for outdoor activities with large public gatherings.
- The assembly that houses the lamp or lamps and can include all or some of the following parts: a housing, a mounting bracket or pole socket, a lamp holder, a ballast, a reflector or mirror, and/or a refractor or lens.
- FLOOD or SPOTLIGHT
- Any light fixture or lamp that incorporates a reflector or a refractor to concentrate the light output into a directed beam in a particular direction.
- A measurable industry standard of illumination equivalent to one lumen per square foot. Measured by a light meter.
- FULL CUT-OFF FIXTURES
- Fixtures, as installed, that are designed or shielded in such a manner that all light rays emitted by the fixture, either directly from the lamps or indirectly from the fixture, are projected below a horizontal plane running through the lowest point on the fixture where light is emitted.
- Light emitting from a light source with intensity great enough to reduce a viewer's ability to see, and in extreme cases causing momentary blindness.
- HEIGHT OF LIGHT SOURCE
- The height of a light source shall be the vertical distance from the ground directly below the centerline of the light source to the lowest direct-light-emitting part of the light source.
- Illuminating Engineering Society of North America (IES or IESNA), the professional society of lighting engineers, including those from manufacturing companies, and others professionally involved in lighting.
- INDIRECT LIGHT
- Direct light that has been reflected or has scattered off of other surfaces.
- The component of a light source that produces the actual light.
- LIGHT TRESPASS
- Light falling where it is not wanted or needed, generally caused by a light on a property that shines onto the property of others.
- OUTDOOR LIGHTING
- The nighttime illumination of an outside area or object by any man-made device located outdoors that produces light by any means.
- PARTIALLY SHIELDED
- In which the bulb of the fixture is shielded by a translucent siding and the bulb is not visible at all. Light may be emitted at the horizontal level of the bulb.
- Lighting that is directed in such a manner as to shine light rays above the horizontal plane.
All residential fixtures with lamps of 600 lumens (about 40 watts incandescent) or less per fixture are exempt from regulation.
All residential and commercial exterior lighting (except floodlights) shall be contained in fixtures with an opaque top and translucent sides (partially shielded) such that the bulb is not directly visible from adjacent and neighboring properties or public rights-of-way.
To minimize light trespass, in residential areas the light level at the property line shall be no greater than 0.5 of a footcandle, measured at a height of five feet above grade.
Commercial property or properties containing mixed uses with a commercial component may not have lighting which exceeds the average minimum levels listed in the IESNA Recommended Publications.
Parking area lights in commercial areas are encouraged to be greater in number, lower in height and lower in light level, as opposed to fewer in number, higher in height and higher in light level. Parking lot lighting shall not exceed average minimum IESNA recommended values.
Pedestrian area lighting shall be fully shielded or full cutoff, not exceed 12 feet in height, with illumination levels no higher than the average minimum IESNA recommended values.
In addition to being in compliance with the other sections, no exterior lighting may be used in any manner that could interfere with the safe movement of motor vehicles on publicly traveled ways. Specifically, all roadway lights and area lights along roadways must be shielded to prevent glare as seen from the road and only placed in areas deemed necessary for safety. Full cutoff fixtures are preferred.
Mercury vapor sources are prohibited from use. The installation, sale, offering for sale, lease or purchase of any mercury vapor fixture or lamp for use as outdoor lighting is prohibited.
Uplighting is only permitted when used as follows:
To light a primary entrance, when the lighting fixture is wall-mounted under an architectural element (e.g., roofs over walkways/entries or overhanging, nontranslucent eaves) so this uptight is captured.
To light local, state, or national flags, when no more than two light fixtures per flagpole are used, with an equivalent total lumen maximum of a 150 watt bulb (incandescent). The fixtures must be shielded such that the lamp is not visible outside a fifteen-foot radius. It is preferred that all flags be lowered at sunset
Highlighting, or illumination, of building facades by use of uplighting is prohibited.
Driveways, and landscaping lighting shall be limited to 35 incandescent watts per fixture per 150 square feet of driveway or landscape area. Fixtures must have opaque tops to prevent the escape of uplighting. Uplighting of trees and shrubs is prohibited.
Floodlighting is only permitted when it is down-directed and fully-shielded such that the lamp is not visible from adjacent and/or neighboring properties. Ground-mounted floodlighting of a structure is prohibited.
Safety and security lighting shall use motion sensors, photocells, or photocell/timers to control duration of nighttime illumination. In all cases the maximum light intensity on the property measured at a height of three feet above grade shall be limited to no more than five footcandles.
Motion sensors are the preferred method for controlling nighttime illumination. The duration of illumination shall be no longer than five minutes after the last detection of motion. Motion sensors are only permitted where the sensor is triggered by activity within the owner's property line. Full cutoff and fully shielded fixtures controlled by photocells may be used in areas requiring maximum security such as outdoor storage yards and at primary points of entrance (e.g., front entries) or in critical common areas for commercial and multifamily properties.
Timer/Photocell combinations may be used, provided the lamps are fully shielded or full cutoff.
Outdoor recreational lighting must be fully shielded and turned off by 10:00 p.m., or at the conclusion of a competition begun before 10:00 p.m. In no case may the lighting remain on after midnight.
All architectural lighting for residential purposes must comply with relevant Historic District Commission guidelines and application procedures.
Linear architectural highlighting (including rope lighting) primarily intended as an architectural highlight to attract attention or used as a means of identification or advertisement is discouraged and must be turned off 30 minutes after the close of public hours.
Blinking, flashing, moving, revolving, scintillating, flickering, changing intensity and changing color lights shall be prohibited except for temporary holiday displays, lighting for public safety or traffic control, or lighting required by the FAA for air traffic control and warning purposes.
Except as noted below, the following types of lighting shall be exempt from the provisions, requirements and review standards of this chapter:
Health, safety, and welfare. If a lighting plan or fixtures are proposed in which the deviations from this code provide demonstrable community and/or health, safety, and welfare benefits, an exemption may be considered. FAA and other federal lighting requirements are considered public safety benefits. The applicant shall submit information to adequately assess the community and/or health, safety, and welfare benefits for approval by the Lighting Enforcement Officer.
Holiday/Winter lighting for residential and commercial properties. The lighting associated with any national, state, local, or religious holiday or celebration is recommended to be lit for no more than six weeks prior and two weeks following the holiday. The light intensity of all holiday lighting shall not exceed 0.5 of a footcandle at the property line.
Approved historic lighting fixtures which may be otherwise nonconforming and which are consistent with the character of the historic structure may be exempted with proof of approval from the Historic District Commission. Approved fixtures shall be consistent with the architectural period and design style of the structure and the lamps shall not exceed 750 lumens (about 50 watts incandescent) per fixture. Lighting utilizing natural gas is also exempt within the context of a fixture meeting the character of an historic fixture.
All temporary emergency lighting needed by the Police or Fire Department or other emergency services, as well as all vehicular light sources, shall be exempt from the requirements of this chapter.
Lighting for temporary commercial use/special events may be requested through the Board of Selectmen, in conjunction with the special events permit.
Unless otherwise specified within this section, within three years of April 1, 2005, all outdoor lighting fixtures that do not conform to requirements of this code must be replaced with conforming fixture or existing fixtures must be retrofitted to comply. Until that time all existing outdoor lighting fixtures shall be considered legal nonconforming fixtures, provided that the existing fixtures may not be expanded or increased in a manner which would result in greater nonconformity.
In the Old Historic District, existing period light fixtures in parking and pedestrian areas may continue to be used beyond the three-year date. However, when such fixtures are upgraded in wattage, or replaced, the new fixtures must have opaque tops and translucent sides such that the lamp is not directly visible.
The Town Administrator will appoint a Lighting Enforcement Officer who will oversee the enforcement of outdoor lighting regulations.
If, after investigation, the Lighting Enforcement Officer finds that any provision of Chapter 102 is being violated, he or she shall give notice by hand delivery or by certified mail, return receipt requested, of such violation to the owner and/or to the occupant of such premises, demanding that violation be abated within 30 days of the date of hand delivery or of the date of mailing of the notice.
If the violation is not abated within the thirty-day period, the Lighting Enforcement Officer may institute actions and proceedings, either legal or equitable, to enjoin, restrain, or abate any violations of this chapter and to collect the penalties for such violations. Any violation of Chapter 102 shall result in a penalty of $100, which may be enforced by means of noncriminal disposition tickets pursuant to Chapter 1 of the Nantucket Code. Each day the violation continues to exist shall be considered a separate violation.