Why is there a large sphere in my water? And flat patches of water too

I am pretty sure the flat patches of water in this image are just a result of slow rendering, so I am less concerned about that than I am the large bright orb in the water. I cannot interact with it and I cannot seem to remove it. I do not know what it is, or how it got there. I want it to go away. I am trying to build a lake of sorts and this is the only instance of this very large orb I can find. Please help me.