Placing string in water causes a visual glitch

I was playing on my friend's realm and I was building in a snow biome so I was useing string and placing it in the water so it would not freeze when I did so it was fine for a bit untill I placed the string next to a solid block and it caused a visual glitch in the water makeing the water disappear only leaveing a few particles of water behind 

 

I have a picture of it