There are several reasons why you're getting water blisters on your body.
Water blisters which are fluid filled blisters can occur on your body due to certain medical conditions, infections, allergic reactions, burns and even friction.
Friction is a common cause of getting water blisters on your body.
Repeated rubbing of the skin that causes friction such as from tools or poor fitting shoes can lead to friction blisters or water blisters on your feet.
Burns such as from exposure to heat, chemicals or even the sun including sunburn can lead to water blisters on the body as a protective response.
Certain infections such as viral infections like shingles, herpes and chicken pox can also cause water blisters to form on your body.
Even bacteria infections like impetigo can cause water blisters to appear on your body.
Allergic reactions to things like certain chemicals, insect bites or poison ivy, poison oak etc can also cause water filled blisters on your body.
And some medical conditions like dyshidrosis which is a form of eczema can cause water blisters on your body and water blisters and blisters in general can also form on the body from frostbite or if a small blood vessel near your skins surface ruptures.
Chickenpox which is a viral infection can also cause water blisters or blisters and itchy red spots on the body which is common in children although adults can also get chickenpox.
Cold sores are small blisters which appear on your lips or around your mouth and is caused by a virus.
Herpes which is an STD or sexually transmitted infection can cause painful blisters that often appear in your genital area.
Shingles which is a reactivation of the chickenpox virus causes a painful rash with blisters on the skin as well.
Contact dermatitis which is a skin reaction to something you've come into contact with such as plants, certain chemicals and soaps may also cause skin rash and water blisters or blisters in general to appear on your skin.
Most blisters on the skin are nothing to worry about and will eventually go away on their own but if not you should see a doctor and have them checked out.