the devil may be in the details.............................
note that if that "water" is in a swimming poolthere are restrictions as shown in 680.8.
I strongly recommend these Meltric plugs and receptacles if you do go ahead, they are rated for wet locations and the receptacle has a permanent spring loaded cover to protect the receptacle when the plug is not installed.
http://www.meltric.com/html/decontactors.html