Bees are often seen winging down to a backyard pool for a drink. This is a guide about keeping bees away from a pool.
Wendy from Las Vegas
In the heat of the summer, bees use water to cool down their hives. They deposit drops of water around their hives and fan the water with their wings. This causes the water to evaporate, raises the humidity inside their nest and cools things down. When you think about it, it makes perfect sense. After all, a nest made out of waxy combs would melt quickly under in the summer heat. Bees also use water to dilute the honey they feed to their offspring. They generally collect water from a source as close as possible to their hives. Unfortunately, once they start using a source, it can be difficult to get them to stop.
I would suggest looking around your yard again to see if you can find the hive. If you can't find it, at least try to track which direction the bees are coming from. Then set up a small birdbath on that side of your yard, preferably as far from your pool as possible. Bees are not particularly fussy about where they collect their water from, so if you can offer them a new water source on their way to your pool, you should be able cut way down on their numbers, if not eliminate the problem entirely.
Bees prefer standing water, so if you have jets in your pool, you might also try adjusting them to create turbulence on the surface of the water. This should be enough to prevent most bees from landing and send them off looking for another source.
Bees don't alway build a hive where one can see it. I have found yellow jacket hives in the ground where they fly out of a small hole in the ground, I have found their nests in side of trees, behind my electric meter and inside my phone box attached to the side of my house. Not always a hive hanging in a tree.