After pushback from environmental groups, Kansas City makes adjustments to its streetlight conversion plan
In January, the Kansas City Council voted 11-1 to replace 84,000 of the city’s streetlights with energy-efficient LED bulbs. The ordinance contracts Black & McDonald to conduct the replacement beginning in May. The large-scale change is expected to last three years.
The LED lights are just one of the projects Kansas City is pursuing to become a more environmentally conscious city.
The high-pressure sodium lights that the city currently uses emit an orange-yellow glow at night. LED lights have a whiter and brighter glow, which concerns some environmental groups.
Though LED lights are more energy-efficient, the city was initially planning on using a 4000 Kelvin color temperature (the high-pressure sodium lights use about 2200K). That high-intensity light is believed to have a negative impact on health and safety.
Choosing a healthy color temperature is vital to residents of the city and the animals that will be affected by the lights. As the color temperature rises, the lights transform from the amber color of traditional lights to a cool white or blue light.
Some might believe that high-intensity LED lights would help road safety, but they can actually increase hazards. According to the American Medical Association, “intense, blue-rich LED lighting can decrease visual acuity and safety, resulting in concerns and creating a road hazard.”
DeAnn Gregory, a member of the local Sierra Club, is concerned about the rapid increase in Kansas City’s light pollution if the city switches to 4000K LED lights.
“We’ll still have all the other light pollution in our community from our commercial buildings and residential homes,” Gregory says. “But because we’re changing to LEDs, we will almost be doubling our skyglow from the streetlights.”
Mary Nemecek, conservation chair for the Burroughs Audubon Society of Greater Kansas City, experienced these hazards while driving in the northland, where she lives. The city has already installed 4000K lights along Barry Road, and the brightness can cause obstacles to drivers.
“I was driving home one night and streets were wet. It’s like driving on the surface of the sun. With the glow from the streets being wet, I could not have seen a child or deer or something,” Nemecek says.
“Bright lights create walls and corners and you can’t see beyond that.”
Nemecek is also concerned about the effect high-intensity bulbs will have on animals. Birds, she says, will be some of the most affected.
Due to its proximity to the Mississippi and Missouri rivers, Kansas City is a major flight path for migratory birds. A recent study from Cornell ranked KC seventh in spring and eighth in fall as most dangerous for migrating birds. Nemecek says that will only get worse if the city increases its existing skyglow with 4000K lights.
“It’s a phenomenon of birds being attracted to light. During migration, they’re going to see that sky glow and be attracted to it,” says Gregory. “That will increase the damage to migration.”
Dr. Vayujeet Gokhale, associate professor of physics at Truman State University and board member of Missouri’s chapter of the International Dark Sky Association, believes the problems with high-intensity LED lights outweigh the benefits. He is concerned with how the bright lights affect all living creatures and their natural rhythms. LEDs that emit a bright white or blue light harm the sleep cycles of those in proximity to the lights—from insects to humans living or working near the streetlights.
“We are completely disrupting that rhythm by introducing artificial light and, in particular, light that contains a lot of blue color,” says Dr. Gokhale. “Pretty much all living things recognize that blue color in a way, shape or form, as associated with daytime.”
After receiving input from environmental activists like Gregory and Nemecek and having conversations with other city leaders across the country that have already switched to LED streetlights, the City Manager’s office is moving forward with only 3000K, dark sky-certified bulbs on all streetlights.
Maggie Green, media relations manager for Kansas City, said there were many reasons the city ultimately chose to move forward with 3000K lights instead of the 4000K that was initially proposed.
“We do have a desire to create a more natural light—on the actual color scale the 3,000k is warmer or more natural than 4000K,” says Green. “Another reason was wanting to have a unified color temperature across all the streetlights and the conversion project instead of a hybrid between two. And, of course, minimizing the impact and interruption to wildlife is another reason that we ultimately decided to pursue 3000 Kelvin.
Green says the city took calls from Lawrence and Overland Park to hear about what worked for those specific cities during their respective streetlight conversions before making their decision to use only 3000K lights.
Gregory was elated to hear that the city was moving forward with a more environmentally-friendly choice in color temperature.
“Kansas City’s choosing better fixtures and warmer white lights will make it easier to see at night by reducing disability glare,” Gregory says. “Informed choices on key infrastructure items like this help reduce unintended negative impacts, conserve the night sky for kids as a natural resource, and reduce harm to bird migrations. Kansas City had an amazing opportunity here and it looks like we’re stepping up to the plate to meet our sustainability goals.”
Seeing how the city responded to environmental concerns and chose the scientifically recommended option was inspiring to Nemecek.
“Every time a small group of citizens makes a difference I am awe-struck, but big credit also goes to the city for listening and stepping up to take another look at the project from all environmental aspects,” Nemecek says.
Switching to LED bulbs would mean saving 2,500 tons in carbon emissions in the first year and 20,000 after three years, according to Public Works. After six years, Public Works estimates that the city will save 28,700 in carbon emissions each year.
Though these benefits exist regardless of the color temperature of the LEDs used, choosing 3000K lights decreases the harm on KC’s natural environment and introduces even more environmental benefits to the switch.
Converting the 84,000 lights to LEDs would also save Kansas Citians’ money, according to a news release from the city. Currently, it costs taxpayers approximately $13 million per year to power and operate and replace the 98,000 total lights in the city. While high-pressure sodium lights last about four years, LED lights last for 10 years or more and use up to 50% less energy than the current bulbs.
It will cost about $21 million to replace the lights, but the city believes that cost will pay for itself in 7-8 years. In the first through third year, the LEDs will save the city $500,000, $1,5 million, and $2.5 million, respectively. After the lights are completely converted, the operations and maintenance savings will be more than $3 million annually from years four-10.
Ultimately, switching to LED lights will help save $27 million over 10 years.
Pending a vote on the budget, work on the conversion project will begin in May of this year.