Chicago plans to replace 270,000 streetlights in the city with LED bulbs, but some experts say that might not be such a bright idea.
To help address those concerns, the city recently extended the public comment period about the new LED lights to Monday, Jan. 9, 2017.
WBEZ’s Monica Eng joins Morning Shift to explore how something as seemingly innocuous as street lights can impact residents’ health and well-being.
Why is Chicago changing its street lights?
Monica Eng: A lot of cities across the nation are changing them because LEDs are really energy-efficient and our old, high-powered sodium lights aren’t. And we’re going to have this master control center where we can see which lights are out and which lights are fine. We can dim them. And the city says that a lot of time is spent just getting complaints from citizens; this way they say they’ll know from a central level when the lights are out.
How long has it been since Chicago changed its lights?
Eng: By most accounts it’s been about 50 years with these high-powered sodium lights. We will be keeping this ‘cobra-head’ look of Chicago lights, but it’s just the actual lights inside (that) will become LEDs. (The new lights) will be more recessed. They sort of pop out now. (The new lights) will be more inside.
If the new lights are more efficient and more controllable, what’s the problem?
Eng: Over the years there’s been a growing body of science looking at blue light and its effects on our sleep, even on the effects of certain cancer drugs to be effective for people. And this growing body of science shows that blue light exposure at night is not good for our health; it can disrupt our circadian rhythms, it can do all sorts of things that they’re learning [about] day to day.
And did you know Chicago was voted by some studies as the most light-polluted city in the world through satellite imaging? A lot of star watchers say this is a great opportunity to finally tell our children, “Look up. Stars.” So that’s an issue too.
How long does someone need to be exposed to blue light before negative effects set in?
Eng: Well, the big studies have been done on night workers and the different health conditions they suffer, they believe, because of that exposure at night. But you’re right, a lot of us don’t walk around looking up at the street lights at night. What people are worried about is something called “light trespass,” where it actually goes inside your bedroom window, even if you have the blinds down or if you have a curtain.
How has the city responded, outside of extending the comment period to Jan. 9?
Eng: They also said, “Hey look, we saw this American Medical Association recommendation that came out this summer advocating 3,000 Kelvins or less, and guess what, our proposal is for 3,000 Kelvins or less.” I talked to Rose Jordan, who is a consultant to the city on this, and she said if light bleeds into people’s windows, she said we can dim it and we can also retrofit it with some shielding right down to the ground where it should go. And there are pros and cons to that. They say that if we reduce the Kelvins we might not have the crispness that would allow for - what some people say - greater visibility or safety.
There is this [question]: “Will brighter streets mean safer streets?” The jury’s still out on that.
Where can citizens preview the new LED street lights?
There’s seven sites out there where you can see what these are going to look like.
This interview has been edited for brevity and clarity. Click the ‘play’ button above to listen to the entire interview.