Blinded by the light
An LED street light in downtown Coeur d’Alene. - Photo by MATTHEW BALL.
A high pressure sodium, or HPS, streetlight on a residential street in Kootenai County. - Photo by MATTHEW BALL
NASA Earth Observatory images by Robert Simmon and Jesse Allen This image of the city lights of the U.S. at night is a composite assembled from data acquired by the Suomi NPP satellite in April and October 2012.
On a clear night during the summer and winter, the bright band of the Milky Way spreads its stars arcing from south to north across the sky.
Because of wasted lighting, though, most Americans and Europeans can no longer see it.
At the turn of the 20th century, much of the night sky, including what observers can see from Coeur d’Alene and North Idaho, was strikingly visible. Now looking up in the sky at night in Coeur d’Alene reveals relatively few stars.
While children used to marvel at the Milky Way, now it remains invisible to most people in town.
Dark skies at night had significant impacts on human cultures throughout history. Starry nights inspire popular mythological characters and stories, according to North Idaho College astronomy instructor Casey Hallett. She also noted that dark skies permitted ancient peoples to create famous constellations like Orion the Hunter.
Today, observers must travel to the mountains east of Coeur d’Alene to see the Milky Way and its thousands of stars, according to Hallett.
Art like Vincent Van Gogh’s Starry Night would not be possible if the artists lived in areas with high levels of light pollution, nor could humans sail the oceans or travel to the moon if they could not view the stars.
So says the International Dark-Sky Association, or IDA for short, an organization dedicated to the preservation of the night sky and education about the impact of light pollution.
It defines light pollution as “the inappropriate or excessive use of artificial lights.”
TOO MUCH LIGHT
Light pollution, while not as well-known as air and water pollution, has significant consequences just like many other forms of environmental hazards.
The IDA expresses concerns about the effects of wasted lighting on economies, safety, health, ecosystems and cultures.
Coeur d’Alene resident Ed Buchler believes light pollution is a serious issue. Buchler belongs to the Coeur d’Alene chapter of the National Audubon Society, and has been an amateur astronomer for more than 50 years.
He’s concerned that Coeur d’Alene’s plan to replace the old streetlight bulbs with Light Emitting Diodes, LEDs for short, will increase light pollution in the Coeur d’Alene area.
He believes replacing the High Pressure Sodium (HPS) bulbs with LEDs in Coeur d’Alene will increase the wasted light amount, which will cost more money and make the streets more dangerous.
Buchler isn’t alone. Residents who live in the Garden Neighborhood near downtown have expressed concern about plans to bring LED streetlights to their area.
According to City Engineer Chris Bosley and City Planner Hilary Anderson, Coeur d’Alene is implementing a plan to have Avista and Kootenai Electric replace HPS lamps with LEDs, which are more energy efficient and last longer.
Anderson and Bosley said the city researches what types of light works best where. For example, local utilities install LED lights near schools and certain residential neighborhoods.
The “cool white” LEDs emit light at a temperature of 4000 Kelvins, according to Avista Senior Communications Manager Debbie Simock. She said the new bulbs’ greater efficiency and directional shielding address the issue of light pollution. Simock said LEDs burn at the same intensity as the HPS they’re replacing.
HIGH COST
OF WASTED LIGHT
But according to the IDA, bulbs at that temperature produce 2.5 times the light pollution as HPS light sources.
IDA states that nationwide, the average city wastes about one-third of the light emitted from streetlights. In a typical year, according to city officials, Coeur d’Alene pays more than $500,000 in electric bills to Avista and KEC. If Coeur d’Alene experiences the average amount of wasted lighting, then light pollution may account for more than $165,000 in unnecessary expenses to the city and residents.
Light pollution does more than waste money. Despite popular belief, studies have shown that brightening cities does not make it safer to travel at night. The Journal of Epidemiology and Community Health conducted a study of lighting in England and Wales in 2015. It found no difference in safety issues no matter what kind of light was used.
The Chicago Alley Light Project, published in 2000, revealed light pollution can make traveling at night dangerous. Criminals can see their targets more easily, whether a person or property. Also, many acts of vandalism occur at night in areas of high light pollution.
Buchler agrees with these studies. He said Coeur d’Alene and area homeowners install bright LED and mercury vapor lights on their houses in an attempt to deter burglars. The new lights only darken shadows.
Driving through areas lit by poorly designed lighting can also be dangerous, according to the American Medical Association in a 2012 report. The glare from overly bright light fixtures can reduce contrasts and hide obstacles from drivers and pedestrians.
According to Buchler, auto manufacturers that install LED bulbs in vehicle headlights exacerbate the glare problem.
The AMA released an additional report in 2016 where it expressed concern about the effects light pollution has on human health. It found that bright lights, especially from blue-white LED fixtures, interfere with sleep. People exposed to the light coming from the LED bulbs experience five times more disruption of their sleep cycle than from HPS lights.
Besides insomnia and lost production, the AMA linked poor lighting to an increased risk of cancer, diabetes and heart disease.
According to the IDA, light pollution also negatively impacts plants and animals, including birds.
Many bird species feed or migrate at night. With bright city lights, traveling avians can get lost or crash into buildings and other artificial structures.
IDA believes not all is lost. Locally, residents can help by installing IDA-approved fixtures on their homes, educating themselves on the impacts of light pollution, getting involved in convincing leaders to enact light pollution measures and visiting and appreciating places which feature dark skies.
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“For my part, I know nothing with any certainty, but the sight of stars makes me dream,” — Vincent Van Gogh.