6.3 Outdoor Lighting Zones

The basic premise of the Energy Code is to base allowable outdoor lighting power on the brightness of the surrounding conditions. The Energy Code contains lighting power allowances for new lighting installations and specific alterations that depend on the lighting zone (LZ) in which the project is located.

Five categories of outdoor lighting zones are defined: LZ0, LZ1, LZ2, LZ3, and LZ4. Lighting zones with lower numbers are darker from LZ0, which is in national parks and other areas intended to be very dark at night, to LZ4 for high-intensity nighttime use, such as entertainment or commercial districts or areas with special security considerations requiring very high light levels. The eyes adapt to darker surrounding conditions, and less light is required to properly see. When the surrounding conditions get brighter, more light is needed to see. Providing greater power than is needed potentially leads to debilitating glare and an increasing spiral of brightness as overbright projects populate surrounding conditions causing future projects to unnecessarily require greater power resulting in wasted energy. The least power is allowed in LZ1, and increasingly more power is allowed in LZ2, LZ3, and LZ4. LZ0 is intended for undeveloped spaces in parks and wildlife preserves and is very low ambient illumination.

The following summarizes the default locations for outdoor lighting zones as specified in §10-114:

• Lighting Zone 0 includes undeveloped areas of government-designated parks, recreation areas, and wildlife preserves.

• Lighting Zone 1 includes developed portions of government designated parks, recreation areas, and wildlife preserves. LZ 1 also includes rural areas as defined by the 2010 United States (U.S.) Census.

• Lighting Zone 4 includes special use districts that may be created by a local government through application to the California Energy Commission (CEC).

Lighting Zones 1-4 are designated according to 2010 U.S. Census definitions for rural areas, urban clusters, and urban areas. See below for details on rural areas, urban clusters, and urban areas and how they are related to lighting zones.

6.3.1 Parks, Recreation Areas, and Wildlife Preserves

The default lighting zone for undeveloped portions of government designated parks, recreation areas, and wildlife preserves is Lighting Zone 0.

The default lighting zone for developed portions of government designated parks, recreation areas, and wildlife preserves is Lighting Zone 1.

The local jurisdiction having authority over the property will know if the property is a government-designated park, recreation area, or wildlife preserve. However, a Lighting Zone 2 designation can be adopted if the property is surrounded by a default Lighting Zone 2 area (as defined by the U.S. Census Bureau). Similarly, when a park, recreation area, wildlife preserve, or portions thereof are surrounded by urban areas (as defined by the U.S. Census Bureau), such areas may be designated as Lighting Zone 3 by adoption of the local jurisdiction. All adjustments in lighting zone designation must be reviewed by the CEC for approval.

6.3.2 Rural Areas

The default for rural areas as defined by the U.S. Census Bureau is Lighting Zone 1. However, local jurisdictions may designate certain areas as Lighting Zone 2 if it is determined that ambient lighting levels are higher than typical for a rural area. Examples of areas that might be designated Lighting Zone 2 are retail stores located in residential neighborhoods or rural town centers that operate during hours of darkness.

6.3.3 Urban Clusters

The default lighting zone for urban clusters as defined by the U.S. Census Bureau is Lighting Zone 2. However, local jurisdictions may designate certain areas as either Lighting Zone 3 or Lighting Zone 4 if it is determined that ambient lighting levels are higher than typical for a rural area. Examples of areas that might be designated Lighting Zone 3 are special commercial districts or areas with special security considerations.

Local jurisdictions also may designate default Lighting Zone 2 areas as Lighting Zone 1, which would establish lower lighting power for outdoor areas with lower surrounding brightness. An example of an area that might be changed to Lighting Zone 1 would include an undeveloped, environmentally sensitive, or predominately residential area within a default Lighting Zone 2 area.

6.3.4 Urban Areas

Lighting Zone 3 is the default for urban areas, as defined by the U.S. Census Bureau. Local jurisdictions may designate areas as Lighting Zone 4 for high-intensity nighttime use, such as entertainment, commercial districts, or areas with special security considerations requiring very high light levels.

Local jurisdictions also may designate default Lighting Zone 3 areas as Lighting Zone 2 or Lighting Zone 1 if deemed appropriate.

Table 6-2: Lighting Zone Characteristics and Rules for Amendments by Local Jurisdictions

Zone	Ambient Illumination	Statewide Default Location	Moving Up to Higher Zones	Moving Down to Lower Zones
LZ0	Very Low	Undeveloped areas of government designated parks, recreation areas, and wildlife preserves.	Undeveloped areas of government designated parks, recreation areas, and wildlife preserves can be designated as LZ1 or LZ2 if they are contained within such a zone.	Not applicable
LZ1	Low	Rural areas, as defined by the 2010 U.S. Census. These areas include single or dual family residential areas, parks, and agricultural zone districts, developed portion of government designated parks, recreation areas, and wildlife preserves. Those that are wholly contained within a higher lighting zone may be considered by the local government as part of that lighting zone.	Developed portion of a government designated park, recreation area, or wildlife preserve, can be designated as LZ2 or LZ3 if they are contained within such a zone. Retail stores, located in residential neighborhood, and rural town centers, as defined by the 2010 U.S. Census, can be designated as LZ2 if the business operates during hours of darkness.	Not applicable.
LZ2	Moderate	Urban clusters, as defined by the 2010 U.S. Census. The following building types may occur here: multifamily housing, mixed use residential neighborhoods, religious facilities, schools, and light commercial business districts or industrial zoning districts.	Special districts within a default LZ2 zone may be designated as LZ3 or LZ4 by a local jurisdiction. Examples include special commercial districts or areas with special security considerations located within a mixed-use residential area or city center.	Special districts may be designated as LZ1 by the local jurisdiction, without any size limits.
LZ3	Moderately High	Urban areas, as defined by the 2010 U.S. Census. The following building types may occur here: high intensity commercial corridors, entertainment centers, and heavy industrial or manufacturing zone districts.	Special districts within a default LZ3 may be designated as a LZ4 by local jurisdiction for high intensity nighttime use, such as entertainment or commercial districts or areas with special security considerations requiring very high light levels.	Special districts may be designated as LZ1 or LZ2 by the local jurisdiction, without any size limits.
LZ4	High	None	Not applicable.	Not applicable.

6.3.5 Determining the Lighting Zone for an Outdoor Lighting Project

Permit applicants may determine the lighting zone for a particular property using the following steps.

• Check with the local jurisdiction having authority over permitting of the property. The local jurisdiction will know if the property is a government-designated park, recreation area, or wildlife preserve, and therefore in default Lighting Zone 0 or 1. The local jurisdiction also may know if the property is contained within the physical boundaries of a lighting zone for which a locally adopted change has been made.

• The lighting zones for urban areas, urban clusters, and rural areas as well as the legal boundaries of wilderness and park areas are based on the 2010 U.S. Census Bureau boundaries. According to the U.S. Census Bureau, there are two types of urban designations, urbanized areas of 50,000 or more people and urban clusters of at least 2,500 and less than 50,000 people. “Rural” areas encompass all population, housing, and territory not included within an urban area or urban cluster.

• The U.S. Census Bureau website can be used to determine if the property is within Lighting Zone 1 (rural areas), Lighting Zone 2 (urban clusters), or Lighting Zone 3 (urban areas). Using an online map overlay tool provided by the U.S. Census Bureau on tool for geographic overlays at https://tigerweb.geo.census.gov/tigerweb/, the property address can be entered to look up geography results indicating whether the address is within an urban area (“2010 Census Urbanized Area” layer), urban cluster (“2010 Census Urban Clusters” layer), or rural area (no layer) or move the map over the region of interest. Blue layers represent the boundaries of urban areas. Purple layers represent the boundaries of urbanized clusters. Figure 6-2 shows a screen image of the U.S. Census Bureau online map overlay tool.

6.3.6 Lighting Zone Adjustments by Local Jurisdictions

The CEC sets statewide default lighting zones. However, jurisdictions (usually a city or county) may change lighting zones to accommodate local conditions. Local governments may designate a portion of Lighting Zones 2 or 3 as Lighting Zone 3 or 4. The local jurisdiction also may designate a portion of Lighting Zone 3 to Lighting Zone 2 or even Lighting Zone 1. When a local jurisdiction adopts changes to the lighting zone boundaries, it must follow a public process that allows for formal public notification, review, and comment about the proposed change.

6.3.7 Lighting Zone Examples of Using Physical Boundaries

Using metes and bounds is a good method to use for defining the physical boundaries of an adopted lighting zone.

“Metes and bounds” is a system that uses physical features of the local geography, along with directions and distances, to define and describe the boundaries of a parcel of land. The boundaries are described in a running prose style, working around the parcel of the land in sequence, from a beginning point and returning to the same point. The term “mete” refers to a boundary defined by the measurement of each straight run, specified by a distance between the terminal points, and an orientation or direction. The term “bounds” refers to a more general boundary description, such as along a certain watercourse or public roadway.

The following examples use metes and bounds to define the physical boundaries of an adopted lighting zone:

• Properties with frontage on Kennedy Memorial Expressway, between First Avenue and Main Street to a depth of 50 ft. from each frontage property line.

• The area 500 ft. east of Interstate 5, from 500 ft. north of Loomis Ave to 250 ft. south of Winding Way.

• The area of the Sunrise Bike Trail starting at Colfax Avenue and going east to Maple Park, the width of a path which is from the edge of the South Fork of the American River on one side, to 100 ft. beyond the paved bike trail, or to private property lines, whichever is shorter, on the other side.

• The area that is bounded by the Truckee River on the West, Grizzly Lane on the south, Caddis Road on the east, and the boundary of Placer County on the north.

Note: The physical boundaries of a changed lighting zone are not required to coincide with the physical boundaries of a census tract.