The purpose of this chapter is to establish regulations and a process to review outdoor lighting to accomplish the following:

A.

Minimize direct glare and prevent excessive lighting, thereby minimizing light pollution caused by inappropriate or misaligned light fixtures, and promoting common courtesy among neighbors; and

B.

Provide sufficient lighting where it is needed to promote safety and security; and

C.

Provide standards for efficient and moderate use of lighting; and

D.

Encourage human health benefits and local wildlife safety.

(Ord. No. 2025-529, § 1(App. A), 4-22-2025)

"Correlated color temperature" or color temperature is a specification of the color appearance of the light emitted by a light source, measured in Kelvin (K). Warmer color temperatures are a lower number, and cooler color temperatures are a higher number.

"Curfew" means the time of day when lighting restrictions are in effect.

"Directional lighting" means methods of directing light downward, rather than upward or outward, with the intention of directing light where it is needed.

"Fully shielded" means a light fixture constructed and installed in such a manner that all light emitted, either directly from the lamp or a diffusing element, or indirectly by reflection or refraction from any part of the fixture, is projected below the horizontal plane (from the bottom of the lamp).

"Glare" means light entering the eye directly from a light fixture or indirectly from reflective surfaces that causes visual discomfort or reduced visibility to a reasonable person.

"Government facilities" means a building or structure, parcel or property, owned, leased, operated, or occupied by the City of Los Altos. Government facilities include any public infrastructure maintained within the City of Los Altos.

"Light pollution" means the material adverse effect of artificial light, including, but not limited to, glare, light trespass, sky glow, energy waste, compromised safety and security, and impacts on the nocturnal environment, including light sources that are left on when they no longer serve a useful function.

"Light trespass" means a condition in which artificial light emitted from a luminaire on one property, not inclusive of light incidentally scattered or reflected from adjacent surfaces, is directed in such a manner that the light source is visible from any other property.

"Lumen" means the common unit of measure used to quantify the amount of visible light produced by a lamp or emitted from a light fixture (as distinct from "Watt," a measure of power consumption).

"Outdoor light fixtures" means outdoor illuminating devices, lamps and similar devices, including solar powered lights, and all parts used to distribute the light and/or protect the lamp, permanently installed or portable; synonymous with "luminaires" affixed to the exterior of a building.

"Seasonal lighting" means lighting installed and operated in connection with holidays or traditions.

"Security lighting" means lighting intended to detect intrusions or other criminal activity occurring on a property or site.

"Skyglow" means the brightening of the nighttime sky that results from scattering and reflection of artificial light by air molecules, moisture, and dust particles in the atmosphere, caused by light directed or reflected upwards or sideways and reduces one's ability to view the night sky.

"String lights" means light sources connected by free-strung wires or inside of tubing resulting in several or many points of light.

(Ord. No. 2025-529, § 1(App. A), 4-22-2025)

A.

All existing outdoor light fixtures installed prior to the effective date of the ordinance from which this chapter is derived shall conform to the provisions of this chapter according to the compliance schedule set forth in Section 14.91.070.

B.

All outdoor light fixtures installed or replaced after the effective date of the ordinance from which this chapter is derived shall comply with this chapter.

C.

For any property subject to this chapter and regulated by permit conditions pertaining to outdoor lighting, the more restrictive provisions in terms of minimizing light pollution shall apply.

D.

Nothing in this chapter shall prohibit a declaration of covenants, conditions, and restrictions for private enforcement from further restricting lighting so long as it meets the minimum standards detailed in this chapter.

E.

The following lighting and activities are not regulated by this chapter:

1.

Indoor lighting.

2.

Construction or emergency lighting provided such lighting is temporary, necessary, and is discontinued immediately upon completion of the construction work or termination of the emergency; provided, however, construction or emergency lighting shall be deployed to comply with the ordinance to the greatest practical extent.

3.

Building or premises address identification lighting that complies with the minimum applicable building or health and safety requirements, provided however, such lighting shall be deployed to comply with this chapter to the greatest practical extent, with the exception of curfew requirements.

4.

Low-intensity landscape lighting which is directed downward and no greater than one hundred and fifty (150) lumens per fixture.

5.

Short-term lighting associated with activities that are otherwise exempt from discretionary or ministerial permitting by the city; provided, however, such lighting shall be deployed to comply with this chapter to the greatest extent practical.

6.

Public Schools Facilities which include athletic fields and parking lot lights.

7.

Government Facilities provided however, such lighting shall be deployed to comply with this chapter to the greatest practical extent, except for curfew requirements.

8.

Lighting at building entrances is subject to all requirements of this chapter except for the curfew requirements in subsection 14.91.040(E) of this chapter.

(Ord. No. 2025-529, § 1(App. A), 4-22-2025)

A.

Shielding.

1.

All outdoor light fixtures shall be fully shielded.

a.

Exceptions to the full shielding requirement include:

1.

String lights when used in occupied residential and commercial decks or patios. String lighting is limited to a maximum of fifty (50) percent of usable outdoor area, and must be extinguished by 11:00 p.m., with a maximum of forty-two (42) lumens.

B.

Light Trespass. Light trespass is prohibited, except for fixtures exempted from this chapter.

C.

Location. Location of outdoor lighting, the following limitations are imposed on the location of outdoor lighting:

1.

Lighting within five feet of the perimeter of a site is prohibited, except where it is controlled by motion sensor which extinguishes the light no later than ten (10) minutes after activation unless otherwise exempted within this chapter.

D.

Lighting Color (Color Temperature). The correlated color temperature of all outdoor lighting shall be three thousand (3,000) Kelvin or less except for seasonal lighting.

E.

Curfew.

1.

Residential Uses: All lighting subject to this chapter shall be extinguished no later than 11:00 p.m., except lighting at building entrances, parking areas and driveways, and lighting activated by motion sensor which extinguishes ten (10) minutes after activation.

2.

Commercial Uses:

a.

All lighting shall be extinguished no later than 12:00 a.m. or close of business, whichever occurs first, except lighting at the building entrances and driveway egress points, and lighting activated by motion sensor which extinguishes ten (10) minutes after activation.

b.

Automated control systems, such as motion sensors and timers, shall be used to meet the curfew requirements for commercial uses. Photocells or photocontrols shall be used to extinguish all outdoor lighting automatically when sufficient daylight is available. Automated controls shall be fully programmable and supported by battery or similar backup.

F.

All outdoor lighting shall comply with applicable regulations in the California Building Standards Code, as may be amended from time to time.

(Ord. No. 2025-529, § 1(App. A), 4-22-2025)

A.

Fuel Station Canopies.

1.

Canopies shall not be transparent or translucent.

2.

Lighting fixtures in the ceiling of canopies shall be fully recessed into the underside of the canopy. All lighting fixtures shall be located to shield direct rays from adjoining properties or public rights-of-way.

3.

Lighting shall not be mounted to the top of facia of canopies.

4.

The maximum light intensity under the canopy shall not exceed an average maintained foot-candle (horizontal) of 12.5, when measured at finished grade. Luminaires shall be of a low level, indirect diffused type.

5.

No luminaire shall be higher than fifteen (15) feet above the finished grade.

6.

The fascia of such canopies shall not be illuminated, except for approved signage.

B.

Outdoor Security Lighting.

1.

All security lighting shall be controlled by a programmable motion detecting device and shall be extinguished within ten (10) minutes.

2.

Security lighting shall be downward directed, fully shielded, and not be mounted at a height that exceeds twelve (12) feet.

3.

Floodlights are not permitted.

4.

Lights intended to illuminate a perimeter are permitted only if such lights do not result in light trespass.

5.

Motion-activated security lights shall not use luminaires that exceed a maximum of one thousand six hundred (1,600) lumens.

(Ord. No. 2025-529, § 1(App. A), 4-22-2025)

A.

Modification of standards from the lighting standards provided in this chapter may be approved for private properties if approved by the development services director or their designee.

B.

Applications to deviate from the lighting standards shall include the following information:

1.

A site plan depicting the location of proposed lighting on the site; and

2.

A lighting inventory that provides, at minimum:

a.

The brightness (in lumens) and correlated color temperature (in Kelvin) of each luminaire; and

b.

The height of each fixture; and

c.

The directional angle of each fixture; and

d.

The character of shielding for each luminaire, if any; and

e.

Identification of luminaires that diverge from the standards of this chapter and are subject to the deviation request; and

f.

Detailed description of the circumstances which necessitate the deviation; and

3.

Other data and information may be required by the development services director.

C.

The deviation may be granted if the following findings are made:

1.

There are unique circumstances affecting the subject property or unique design and land use characteristics that make it infeasible or impractical to comply with strict application of the lighting standards detailed in this chapter.

2.

The proposed deviation will achieve the intent of this chapter to the maximum extent feasible.

3.

The proposed deviation is to provide necessary security and/or safety lighting of the subject property.

D.

Notice of the development service director's decision to approve the requested deviation shall be posted by city staff or, to their discretion, the applicant, and it shall be legible and visible from the public right-of-way. Such notice shall state the decision on the application and shall provide information on the appeal process pursuant to this chapter.

E.

Appeal Procedures.

1.

An appeal of the development service director's decision shall be in writing and filed with the city clerk within fourteen (14) days after the date of the notice of the decision. The appeal shall be accompanied by a fee, as set by the city council, and shall clearly state the reason for the appeal.

2.

Upon receipt of such an appeal, the city clerk shall notify the development service director and the applicant and shall set a time for an administrative appeal hearing with the city manager as soon as practical but within thirty (30) days after the receipt of such an appeal.

3.

Notice of the appeal hearing shall be published in a newspaper of general circulation, and state the decision being appealed, date, time, and location of the appeal hearing.

4.

The city manager shall conduct a de novo hearing of the application. At the close of the hearing, the city manager may affirm, reverse or modify the decision of the director, or refer the matter to the director for further consideration as may be directed by the city manager. The city manager's decision following the appeal hearing will be final.

(Ord. No. 2025-529, § 1(App. A), 4-22-2025)

A.

Effective Date. The effective date of this chapter shall be May 1, 2025.

B.

The following requirements shall apply to existing outdoor light fixtures within one year of the effective date of the ordinance from which this chapter is derived:

1.

Existing outdoor light fixtures with the ability to be redirected shall be directed downward to minimize sky glow, glare and in a manner to minimize light trespass onto adjacent properties.

2.

Existing outdoor light fixtures that have adjustable dimmers shall be dimmed to minimize glare and light trespass onto adjacent properties.

3.

Existing outdoor light fixtures that are motion sensor equipped shall be programmed to extinguish not more than ten (10) minutes after activation.

C.

Compliance Period. Notwithstanding the provisions in section B of this section, a property owner shall comply with the remaining requirements of this chapter in association with any site improvements set forth below:

1.

Construction of a new single-family dwelling.

2.

Construction of a new residential development with two or more dwelling units.

3.

An addition to an existing residential development that within a five-year period adds and/or replaces fifty (50) percent or more to the developments existing habitable square footage that is known and provided on the latest County of Santa Clara Assessors Office Tax Roll.

4.

Construction of a new non-residential development.

(Ord. No. 2025-529, § 1(App. A), 4-22-2025)

A.

Authority and enforcement of this chapter shall be enforced as prescribed in Title 1 of the Los Altos Municipal Code.

B.

Each violation of this chapter shall be considered a separate offense.

1.

First violation shall result in a written warning.

2.

Second violation shall result in an infraction of one hundred dollars ($100.00).

3.

Third violation shall result in an infraction of two hundred dollars ($200.00).

4.

Fourth violation and subsequent shall result in an infraction of five hundred dollars ($500.00).

(Ord. No. 2025-529, § 1(App. A), 4-22-2025)

Nothing in this chapter is intended to or shall be interpreted as conflicting with any federal or state law or regulations.

(Ord. No. 2025-529, § 1(App. A), 4-22-2025)

If any section, subsection, subdivision, paragraph, sentence, clause, phrase, or portion of this chapter is, for any reason, held to be invalid or unconstitutional by any court of competent jurisdiction, such a decision shall not affect the validity or effectiveness of the remaining portions of this chapter. The city council hereby declares that it would have adopted this chapter and each section, subsection, subdivision, paragraph, sentence, clause, phrase, and portion of this chapter irrespective of the fact that one or more, sections, subsections, subdivisions, paragraphs, sentences, clauses, phrases, or portions thereof may be declared invalid or unconstitutional to this end, the provisions of this chapter are declared severable.

(Ord. No. 2025-529, § 1(App. A), 4-22-2025)