Breaking Sign that is Supporting Water then replacing the sign create's a source of water on the floor

I was in the End and I jumped down to go to my server's Enderman Spawner so I jump down to a Water source supported by a sign...

Then I looked it and for some stupid reason broke it, Then realized that it would make water go everywhere, So I replace it...

Then I look down and a Source Block of Water was on the floor (Flowing) and I had to place a book on the Water to stop it...