It’s a common question. “My child has a surgically placed feeding tube. Can they go in the water?” To answer there’s some context required so it’s best to consult with your physician. This is especially true if the tube site is less than 6 months old. Assuming the tube site has completely healed from the surgery and the stoma is well established, the rest of the post applies to you.
If your child gets in the water and the water goes through his stoma it lands in his stomach which is the exact same place it would end up with any other child. There are plenty of places where swimming is simply a bad idea. Lakes can grow many different types of bacteria which can make you sick. If you’ve been swimming in a lake your whole life you’ve probably already been exposed to whatever is in it and it’s unlikely you’ll get sick. A child who has never swum there before might get very sick from that same bacteria.