We have new LED street lights in Flagstaff, Arizona, which is a Dark Sky City. The city installed them in my neighborhood 1st and wanted feedback. They are yellow or orange in color and are not supposed to effect the night sky. We have the Lowell Observatory here so that is important.
I don't know yet if they actually do affect the night sky. Can you trust the city? I have been taking readings and can't get readings as dark as I used to but it could be because it is winter and we have neighborhood smoke and snow and Christmas lights that might also affect the sky.
Yes, the LED lights can be turned down but they haven't done that. They did it on one light in our neighborhood as a test and it was somewhat less bright. Some noticed it and some didn't so the dimming isn't substantial and this is on level 0. The lights are a lot brighter than what we had and when my wife and I go for walks at night we don't like all the glare. Not much we can do. I have been working with the city and there is the possibility of only using lights at intersections for our neighborhood but this depends on feedback from the community and I have my doubts that most will want this even in Flagstaff. People seem to feel safer with more light.