I don't have experience using it with livestock/chickens, but I do with people.
If you really want to do this, and I don't think I ever would even tho' I'm on a well, I can offer this info:
I would first get a swimming pool test kit (or better) specifically for chlorine.
Most
city water , when tested, barely registers as a trace of chlorine with a test kit. In most areas, it's supposed to be .02ppm (parts per million) when it leaves the treatment plant, so it's usually lower when it gets to the homeowner, but that also depends on how far it travels, the condition of the pipes, etc.
As a comparison, a public swimming pool should not be over 2ppm as anything beyond that causes eyes to burn, itchy/burning skin, and can cause stomach upset,
but is not
harmful to
humans at that level. As mentioned already, several things cause chlorine to dissipate; heat, sun, time...
When my Sailors or Marines had field exercises, we'd have them treat their 'buffalo's", one of their big water tanks on a trailer (400 to 600 gals), with a small coffee cupful of bleach (8 oz), and even then it was usually a little strong for the first day; just to give an idea of how little is needed by volume IF your water is considered potable to start with (city or an approved well). I also took into account that my beloved Devil Dogs often picked up a dirty garden hose and dropped it into the buffalo to fill it...
So we're talking about an almost 200lb human vs a less than 10lb chicken that eats dirt...
Sorry! Prolly more than you wanted to know,
but sometimes it helps me to have a reference point when I have questions! Hope this helps your decision...