If the pools are kiddie pools. You have NOTHING to worry about.
This is my Silkie hen in the ducks pool the other day. She LOVED it. If the water is lower than the the chicken's heads, they will be just fine. My chickens even swim in our larger pool.
I found that the ducklings pooped in the chickens drinking water, so in order to prevent problems later on down the track , I separated them. I'm not concerned about full grown chooks drowning, I thought we were discussing " chicks " and a chick can drown in 2 inches of water.
I had a kiddie pool with steps so the ducks could get out... Much deeper than silkiesforever and I found my six week old barred rock at the bottom one morning. Very sad. My ducks and chickens have been seperated ever since. It might work just fine half full but rouens LOVE going all the way under and swimming around so I gave them their own private area and the same for the chickens.
I lost my rooster in a larger pond. Took it out and put a kiddle pool in and non of the chicks have tried to get in it. They drink from the outside but never climb in. They were about 7/8weeks old when we pit the pool in.
Baby chicks fall into water and drown, this can even happen with their drinking water but I have never had a pullet or adult chicken drown in a pond or a wading pool, Our current flock has had access to our pool over a 3' fence but I have never seen them go in or fall in and actually seldom even go in the deck around it. Maybe it's because we make sure they always have access to clean drinking water.
You guys have given me something to think about. We have a spring fed watering trough in our barnyard about 2-3feet deep. I was thinking my chickens might use it for a waterer during the day free ranging. My guys are just 3 weeks now and haven't been out there yet. I was thinking in terms of when they are full grown. Might need to make some modifications.
Once they are older you shouldn't have any problems, but for now a brick or some strategically placed flat river stones will go a long way towards saving your little ones, if they get into trouble.
i have 2 ducks with a kiddy pool along with 12 chickens and they do fine chickens may hop up on pool to drink but haven't fell in pool so far the ducks love it to bathe in and for a treat sumtimes I put live minnows in the pool for the ducks and they go crazy over it I have a Cayuga and khaki cambel duck which are laying eggs now sumtimes I get double yolk eggs from them