Dark Sky Rules: Altadena vs Santa Clarita
How do dark sky rules rules compare between Altadena, CA and Santa Clarita, CA?
Altadena and Santa Clarita have similar restriction levels.
Altadena, CA
Los Angeles County
LA County's Rural Outdoor Lighting District (ROLD) ordinance, effective 2012, requires fully shielded outdoor lighting and prohibits light trespass in designated rural unincorporated areas. The ROLD covers mountain and rural communities. Mercury vapor lights and drop-down lenses are prohibited.
View full Altadena rules →Santa Clarita, CA
Los Angeles County
SCMC 17.51.050 requires all light sources to be directed downward and shielded. Lighting must not spill over to adjacent properties or create glare.
View full Santa Clarita rules →Key Facts Comparison
| Fact | Altadena | Santa Clarita |
|---|---|---|
| ROLD | Effective since 2012 | - |
| Shielding | All outdoor lighting must be fully shielded | Required — downward directed |
| Mercury Vapor | Prohibited | - |
| Applies To | Rural unincorporated areas | - |
| Spillover | - | Prohibited to adjacent properties |
| Glare | - | No direct glare permitted |
| Code Section | - | SCMC 17.51.050 |
Highlighted rows indicate differences between cities.
Altadena FAQ
Does LA County have dark sky rules?
Yes. The Rural Outdoor Lighting District (ROLD) ordinance restricts outdoor lighting in rural unincorporated areas. It requires full shielding, warm color temperatures, and maximum lumen limits to reduce light pollution.
Am I in the ROLD?
The ROLD covers rural unincorporated communities in the Santa Monica Mountains, northern LA County, and other designated areas. Check with the Department of Regional Planning at (213) 974-6411 or review the ROLD boundary maps on planning.lacounty.gov.
What type of outdoor lights are allowed in ROLD areas?
Fully shielded fixtures (no upward light emission) with warm white color temperature (below 3000K recommended). Maximum lumen output varies by fixture type and location. All new fixtures must be ROLD-compliant.
Santa Clarita FAQ
What does fully shielded mean?
The fixture must direct all light downward with no light emitted above the horizontal plane. This prevents glare and sky glow while still providing ground illumination.
Can my neighbor's lights shine into my yard?
Most codes prohibit light trespass onto neighboring properties. Contact Santa Clarita code enforcement if outdoor lights from adjacent properties create a nuisance.
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