CITY OF MALIBU LIGHTING ORDINANCE

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1 CITY OF MALIBU LIGHTING ORDINANCE Comparison of POLC and MLO Model Ordinances James Benya with Scott Kardel Background Over 50 years ago astronomers first recognized light pollution to be a growing problem. Even then, outdoor lighting was causing artificial sky glow, making astronomy increasingly difficult. The need for outdoor lighting continues to grow with population, and today nearly 2/3 of North Americans can no longer see the Milky Way on a clear night from their homes. More recently, research has begun to show evidence of a number of potential environmental and health risks associated with excessive light at night. Malibu fortunately has suffered only minimal light pollution. In 2013, Malibu s City Council decided to undertake the adoption of an outdoor lighting ordinance to prevent further light pollution and to mitigate current problems. Malibu retained the International Dark- Sky Association to assess candidate model or pattern lighting ordinances worthy of consideration for adoption, and to assist Malibu in adopting one to help protect the natural night environment that remains mostly preserved all around and within the Malibu City Limits. Candidate Model Ordinances A model ordinance is developed to aid and expedite ordinance development by a city or other governing body. Because cities usually do not have expertise on staff capable of writing a technically correct document, adopting a model ordinance is far less expensive than hiring a group of experts to write one from scratch. The Pattern Outdoor Lighting Code (POLC) and the Model Lighting Ordinance (MLO) are the two best competing model lighting ordinances in North America. The MLO was developed and is officially sanctioned jointly by the International Dark- Sky Association and the Illuminating Engineering Society (IES). Astronomers and city staff in Flagstaff, Arizona developed the Flagstaff (AZ) lighting ordinance upon which the POLC is based. Among the many ordinances developed in North America in the last decade, these two stand alone as comprehensive ordinances from which Malibu could craft a municipal lighting ordinance. Both were written with legal and planning advice from other communities and have been adopted by several communities. Malibu Lighting Ordinance 1 POLC/MLO Study

2 What is Light Pollution and How to Stop It Light pollution can be broken down into three primary types: Artificial sky glow, caused by light directed upward into the sky. Light is scattered by air molecules and appears to glow. This effectively hides the stars, especially the dimmer ones that make up the Milky Way and lesser constellations. Glare, visual discomfort or reduced visibility caused by lights that are too bright and not shielded from view. Light Trespass, caused by lights that shine from one property onto another without permission. Among humans light trespass can impact the visual environment, often leading to conflict between neighbors. Light trespass into natural habitat can upset Nature s rhythms of living beings and their nocturnal resting, predation or feeding cycles. Reducing the amount of light radiated into the environment is the first way to mitigate light pollution. The quantity of light is measured in lumens, and both candidate lighting ordinances regulate the number of lumens allowed to a site. For instance, a commercial business site might be allowed 100,000 lumens of light. How it is used is up to the site designer or owner, so that important features of the site might be more brightly lighted than others by design. The second way to mitigate light pollution is to require all lighting to project light downwards. Shielded lighting usually does not trespass onto adjacent sites, and has relatively little glare. This means that many popular styles of lights will be prohibited or have their use strictly restricted. The third way to mitigate light pollution is to control the glare of individual lights, even if they shine downwards. Lights that are too powerful for the application usually cause glare, Regulations help lighting designers and installers to select among lights that are just powerful enough for the application. The fourth way to mitigate light pollution is to turn lights off or dim them when they are not needed. If most commercial lighting is extinguished after human activity hours in the evening, a darker sky remains for late evening enjoyment and better sleep, with less impact on the natural world. A fifth way to mitigate light pollution is to require the use of light sources whose color has the least impact. For instance, yellow light is known to be unattractive to insects, and to many other species as well. Blue light in particular has the greatest negative affect on astronomy as well as the circadian rhythms of living beings. Because white light includes all colors of light, attenuating or eliminating some wavelengths is often a good way to mitigate light pollution, especially in the most environmentally or astronomically sensitive locations. Other Aspects of Ordinances Ordinances must be enforceable and adapt to the needs of the community. Considerations range from reasonable exceptions and exemptions, like seasonal lighting or construction lighting, to the differences between commercial and residential lighting. There are also a host of practical and enforcement concerns, such as additions to existing lighting systems, how to address repairs to existing lighting, and when all lighting must be changed to meet the ordinance. While many of these considerations are part of any city ordinance or code, it helps cities to enforce the provisions if good requirements are already contained in the model ordinance. Malibu Lighting Ordinance 2 POLC/MLO Study

3 Comparing the Two Model Ordinances Overall, both candidate ordinances are similar in that they: Are complete ordinances with definitions, applicability, and other necessary sections. Have about the same number of pages and the same level of complexity. Provide an overlay zoning system that allows parcels to be assigned a lighting zone based on their land use and relative sensitivity to light. Restrict total site lumens by zone using a lumens per acre formula. Require shielding by zone, with increased shielding for more sensitive areas. Require lighting to be reduced after hours. Have supporting sections for enforcement. Have separate requirements for homes and for non- residential lighting. Have sections that can also be applied to street lighting (except those governed by Caltrans). Detailed Discussion The attached comparison Table A lists the two ordinance sections and topics. In general, both model ordinances have similar contents and have similarly demanding requirements. There are some differences between the two, however, discussed as follows: 1. The POLC is based on parcel acreage, and the MLO is based on developed site area. The MLO allows more light as the percentage of the developed parcel increases. The POLC allows the same amount of light for sites regardless of percentage of development. 2. Using the POLC, total site lumens are the product of site acreage times zone allowance, plus allowances for service stations and sports areas. The MLO has two methods for determining the total amount of lumens allowed, the Performance Method and the Prescriptive Method. In the Prescriptive Method the total site lumens are the product of either the number of parking lot spaces times a per space allowance, or the amount of hardscape times a per square foot allowance; in the latter case, plus additional allowances for service stations, and certain other uses. The Performance Method is best for projects with complex lighting requirements or when the applicant wants or needs more flexibility in lighting design. 3. In general, the MLO will permit meeting IES light level recommendations contained in the IES Lighting Handbook, 10 th Edition, with fully shielded luminaires. The POLC does not have a direct relationship with IES recommended practices or standards. 4. For conventional lamps, the POLC employs initial lamp lumens; the MLO also employs initial lamp lumens, but reduced by the luminaire efficiency. Both use absolute fixture lumens from LED lamps. 5. The POLC has two lighting zones that are essentially rural and urban (LZ1 and LZ2). The MLO has five zones (LZ0, LZ1, LZ2, LZ3 and LZ4) correspond to IES and Malibu Lighting Ordinance 3 POLC/MLO Study

4 International Commission on Illumination (CIE) lighting zones for design standards. The two zones of the POLC do not correlate any national or international standards. 6. MLO zones LZ0 and LZ1 are the most restrictive. MLO zone LZ2 and POLC zone LZ1 are approximately equal in stringency. MLO zone LZ3 is slightly less restrictive than POLC LZ2. MLO zone LZ4 is considerably more lenient, and will probably not be used in Malibu. 7. The POLC has spectrum (color temperature and light source) requirements and prohibitions on some light sources. It uses a three color- class system to differentiate among broad- spectrum light sources and more environmentally and astronomically benign sources, making the latter required under conditions where color rendering does not matter. The MLO does not. 8. The MLO employs the BUG (Backlight- Uplight- Glare) system for controlling individual luminaire brightness and offsite impacts. The BUG system is included in IES Technical Memorandum TM The POLC is silent on the BUG system and has no restrictions for backlight or glare. Instead, the POLC uses illustrations and a generic description to define fully shielded, partly shielded and unshielded luminaires. 9. The POLC has a general requirement that street lighting meet all ordinance limits except lumen restrictions. The MLO has an optional requirement that all street lighting be fully shielded. 10. The POLC has specific restrictions for sports lighting, including light levels, shielding, etc. But it is not complete for all types of sports. The MLO requires a comprehensive study of off site impacts for sports lighting but does not impose specific restrictions. 11. The POLC addresses sign lighting. The MLO does not (with the intent of having a separate sign ordinance). 12. The MLO addresses amortization. The POLC does not. 13. The POLC provides specific directions regarding submissions, approvals, and penalties. The MLO reserves a section for the community to develop its own processes and procedures. 14. The POLC restricts the sale of non- conforming light fixtures. The MLO is silent on this topic. 15. For residential lighting, the POLC has a fixed maximum number of lumens per home. The MLO has a per- luminaire limit according to lighting zone. The POLC allows some partially shielded lighting but appears to prohibit landscape lighting. The MLO allows low voltage landscape lighting in lighting zones LZ2- LZ4 but not in LZ0 or LZ1. As an overarching consideration, all model ordinances are written without regard for the structure of the codes of specific communities, so the first order of business should be for City staff to determine the Sections and Subsections, including outline content, to which the City of Malibu Outdoor Lighting Ordinance should be written. This may tend to favor major portions of one of the model ordinances over the other. Malibu Lighting Ordinance 4 POLC/MLO Study

5 Sample Projects In order to determine which of the ordinances is more restrictive, three projects were studied: A theoretical 2- acre site based on an aerial image of a portion of a commercial development in which there is quite a bit of undeveloped land (Chart 1). A theoretical 23- acre site based on an aerial image of a commercial development with a relatively high level of site hardscape development, especially including large parking lots and large service yards (Chart 2). An actual recent development in Malibu (Trancas Country Market) totaling about 10 acres, which was successfully designed to meet MLO LZ2. (Chart 3.) Trancas Country Market later changed several luminaires and reached LZ1 compliance overall. Trancas Country Market is a particularly important study because the project is almost complete and the quality of light and how the design preserves the night sky can be assessed. The sample projects study shows no advantage of the lighting zones and lumen allowances of the POLC. The lumen allowances in MLO zones 0, 1 and 2 are the same or less than POLC LZ1, and MLO LZ3 is about the same as POLC LZ2. From the data and comparisons, MLO LZ- 0 could be applied to the most environmentally sensitive and visually demanding areas; LZ- 1 can be applied to residential and commercial areas west of the city center, and LZ- 2 can be applied to commercial districts east of the city center. LZ- 3 could be held in reserve for extremely special projects in the future. There is probably no place for LZ- 4 in Malibu. One advantage of the POLC is its control over light source color (spectrum). Because the POLC was derived from the Flagstaff (AZ) ordinance designed to address astronomical concerns for Lowell Observatory, its requirements are as critical as similar ordinances in Tucson, AZ and near Palomar Mountain near San Diego. We see this as an opportunity to control the ambience and environmental sensitivity of Malibu and propose a test mockup of candidate light sources as part of the project. Summary The result of this study is that we believe that Malibu should adopt a modified version of the MLO to include the items below but without its Performance Method. It is generally agreed that the MLO s Performance Method was developed to accommodate unusual projects, but for Malibu it is too complex and generally unnecessary. Otherwise, the MLO should be modified to incorporate several features of the POLC, including: Control of light color (spectrum) A reduced number of zone types, employing LZ0, LZ1 and LZ2 with the ability for specific projects or parcels to apply for LZ3. LZ4 should not be allowed. Include various application and enforcement sections from either document depending on Staff and City Attorney input. Malibu Lighting Ordinance 5 POLC/MLO Study

6 Table A. Section- by- Section Model Ordinance Comparisons Pattern Outdoor Lighting Code (POLC) Section 1: Purpose and Intent Section 2: Conformance with Applicable Codes Section 3: Applicability 3.1 New Uses and Major Additions 3.2 Minor Additions 3.3 Resumption of Use After abandonment 3.4 Public Roadways Section 4: General Outdoor Lighting Standards 4.1 Shielding requirements 4.2 Total Outdoor Light Output Standards 4.3 Lamp Type Standards 4.4 Spotlight aiming standards 4.5 House Side Shielding Requirements 4.6 Effective shielding standard 4.7 Multi class shielding standard 4.8 Luminous tube lighting 4.9 Internally illuminated architecture 4.10 Indoor lighting 4.11 Time limits Section 5: Outdoor Advertising Sign Lighting Standards Section 6: Special Use Lighting Standards 6.1 Recreational facilities 6.2 Frontage row of vehicle display areas 6.3 Service station canopies 6.4 Other Lighting on Parcels with Special Uses Model Lighting Ordinance (MLO) Part I. Preamble Part II. Lighting Zones Part III. General Requirements A. Conformance with Applicable Codes B. Applicability C. Lighting Control requirements Part IV. Non- Residential Lighting A. Prescriptive Methods Per Parking Space Hardscape Area B. Performance Method Part V. Residential Lighting A. General requirements B. Requirements for Landscape Lighting Part VI. Lighting by Special Permit Only A. High Intensity and Special Purpose Lighting B. Complex and non- Conforming Uses Malibu Lighting Ordinance 6 POLC/MLO Study

7 Section 7. Submission of Plans and Evidence of Compliance with Code, Subdivision Plats 7.1 Submission Contents 7.2 Additional Submission 7.3 Subdivision Plats 7.4 Lamp or fixture substitution 7.5 Plan Approval 7.6 Certificate of Installation Section 8 Prohibitions 8.1 Sale of non- Conforming Fixtures and Lamps 8.2 Laser Source Light 8.3 Searchlights Section 9 Temporary Exemption 9.1 Request 9.2 Approval and Duration 9.3 Disapproval Section 10 Other Exemptions 10.1 Non- conformance 10.2 State and Federal Facilities 10.3 Emergency Lighting 10.4 Swimming Pool and Water Fountain Lighting Section 11 Appeals Section 12 Law Governing Conflicts Part VII. Existing Lighting A. Amortization B. New Uses or Structures; Changes of Use C. Additions or Alterations Part VIII. Enforcement and Penalties Part IX. Tables Part X. Definitions Part XI. Optional Street Lighting Ordinance Section 13 Violation and Penalty Section 14 Severability Section 15 - Definitions Malibu Lighting Ordinance 7 POLC/MLO Study

8 Comparisons of Allowed Site Lumens Malibu Lighting Ordinance 8 POLC/MLO Study