The use of outdoor lighting is often necessary for adequate nighttime safety and utility, but common lighting practices can also interfere with other legitimate public concerns. Principal among these concerns are:

The concerns of safety, utility and aesthetic appearance need not compete. Good modern lighting practices can provide adequate light for safety and utility without excessive glare or light pollution. In nearly all cases, careful attention to when, where and how much nighttime lighting is needed will lead to better lighting practices.

The topography and atmospheric conditions in Carbon County are uniquely suited for government, military, commercial, and private astronomical observation in the area. Unnecessary or excessive uses of outdoor nighttime lighting have an adverse impact on astronomical observation even at relatively great distances.

Accordingly, it is the intent of this code to require lighting practices and systems which will minimize light pollution, glare, light trespass, and conserve energy while maintaining nighttime safety, utility, security and productivity.

In support of dark skies, events will be held twice a year to educate our community both about the value of this effort as well as about the sky itself. These events will be coordinated by Helper City Public Library and may include visiting speakers and the creation of a dark skies community club or committee.

Enforcement of this effort will be conducted by the enforcement officer under the direction of the police chief and mayor. Appeals will be made directly to the Helper hearing officer.

Exemptions.

Temperature of Lamps. Lamps shall not exceed a maximum correlated color temperature (CCT) of 3,000 degrees Kelvin.

Lamp and Shielding. All light fixtures over 1,500 lumens are required to be fully shielded and installed so that the shielding complies with the definition of a fully shielded light fixture.

Light Trespass Standard. All light fixtures, including motion sensing fixtures and security lighting, shall be aimed and shielded so that the direct illumination shall be confined to the property boundaries of the source, including any public or private street or road.

Signs.

Parking Lots.

Gas Station Canopies. Gas station canopies may be illuminated, provided all light fixtures are mounted on the undersurface of the canopy, all light fixtures are full cutoff and diffusers are not visible from locations off the property. Except for directed beam lighting, merely placing the fixtures on the underside of the canopy does not qualify as fully shielding the light fixture. Directed beam lighting mounted under the canopy is allowed, provided the light source cannot be seen from outside the property boundaries.

Total Outdoor Light Output Standards – Nonresidential and Multifamily Uses.

Total Outdoor Light Output Standards – Single-Family Residential Uses.

Roadway/Streetlights. Streetlights are allowable as recommended by the public works administrator or city council. All streetlights shall utilize lamp types that are energy efficient and minimize sky glow and other negative impacts of artificial lighting. They shall not exceed 10,000 lumens per net acre. Lighting shall meet safety concerns with a goal of using the lowest levels of lumens necessary.

New Public Lighting – Streetlights/Public Property and Rights-of-Way.

Prohibited Lighting.

Light fixtures with motion sensors and/or timers are required to minimize the duration of nighttime lighting.

Fully shielded fixtures are required where any lights, even those below 1,500 lumens, are mounted on structures or poles higher than the first level above ground level to protect the view of the night sky, minimize ground reflection, and reduce light scatter beyond the property line.

Statuary and flags shall be lit from above to minimize sky glow.

New Uses, Buildings and Major Additions or Modifications. If the total cumulative increase in floor area is greater than 50 percent for single-family residential or greater than 25 percent for all other uses, or if the total cumulative cost of any exterior modification, alteration or repair is greater than 25 percent of the valuation of the building as determined by the appointed city council member, then all outdoor lighting fixtures shall meet the requirements of this code for the entire site, including previously installed and any new outdoor lighting. Cumulative modification or replacement of outdoor lighting constituting 25 percent or more of the permitted lumens for the parcel, no matter the actual amount of lighting already on a nonconforming site, shall constitute a major addition for purposes of this section.

Minor Additions. If the total cumulative increase in the floor area is 50 percent or less for single-family residential or 25 percent for all other uses, or if the total cumulative cost of any exterior modification, alteration or repair is less than 25 percent of the valuation of the building as determined by the appointed city council member, then full conformance of the existing portion of the building or structure is not required. However, such projects shall require the submission of a complete inventory and site plan detailing all existing and any proposed new outdoor lighting.

New Lighting. Any new lighting on the site shall meet the requirements of this code with regard to shielding and lamp type; the total outdoor light output after the modifications are complete shall not exceed that on the site before the modification, or that permitted by this code, whichever is larger.

Resumption of Use after Abandonment. If a property or use with nonconforming lighting is abandoned, nonconforming situations, then all outdoor lighting shall be reviewed and brought into compliance with this code before the use is resumed.

Existing Lighting.

Public Roadways. In general, this code does not apply to city and state rights-of-way or the Union Pacific rail yard but efforts will be made to discuss and bring the rail yard into line as much as possible. However, all such street lights must be fully shielded.

The penalty for violation of any portion of this chapter shall be: