East Alameda County supports dark sky preservation near Lick Observatory. Title 17 requires shielded full-cutoff fixtures in rural and hillside zones, stricter near the observatory influence area.
Dark sky protection in Alameda County balances urban lighting needs in the East Bay with preservation of astronomical observing conditions at UC Lick Observatory on Mount Hamilton (just over the Santa Clara County line but affected by Alameda County emissions). Unincorporated Alameda County, especially rural areas near Sunol, Livermore, and the south county hills, applies enhanced outdoor lighting standards. Requirements typically include full-cutoff fixtures that emit no light above the horizontal plane, low-pressure sodium or warm LED sources (2700K or lower correlated color temperature preferred), motion sensors for security lighting, and curfews for non-essential lighting after 10 or 11 PM. Commercial parking lots require shielding and pole height limits. Livermore city has separate dark sky ordinance protecting the observatory view. Violations are typically code enforcement matters addressed through warnings and citations.
Contact your local code enforcement office for specific penalty information.
Other ordinances people look up for this city. Green dot = verified primary-source excerpt.
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Alameda County NPO §6.65.030 prohibits parking or storing vehicles on lawns or unimproved surfaces of residential property. Vehicles must be on paved concret...
Side-by-side rule comparisons with other cities in Alameda County.
See how other cities in Alameda County handle dark sky rules.
See how Castro Valley's dark sky rules rules stack up against other locations.
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