All good suggestions above.
during really cold spells I’ll give my flock wet mash (feed + water to a batter consistency), they get water that way. We also find they drink fresh water best- so when we put fresh water into the waterer they are very thirsty then.
once we had a bucket de-icer. It went into the plastic bucket and was meant to just keep the water from freezing (so not warming the water much beyond 40F). But the cage around me the heating element was welded with a rusting material, so the water was rusty...very quickly even after it would get changed. The girls would not drink the rusty water. So we got a bucket heater for livestock (rated for a 5 gallon bucket). WOW-it made the water quite warm and the girls would not drink that either.
I egg production quickly suffers when water consumption is low. So, if there has been a recent reduction in egg production that could be an indicator of not drinking enough water.
Good luck.