What are the radical names?
In my opinion, 三点水 and shui3 are all correct names for 氵, so for 饣.

Actually, 氵is also 水, just in another face. 
You can know this by comparing Chinese Seal Character(小篆)
河:http://www.zdic.net/z/1c/zy/6CB3.htm
水:http://www.zdic.net/z/1c/zy/6C34.htm

三点水 is more formal, shui3 is most used in computer world.

Hope my explanation can help you understand this further.