I have built an Iron golem farm : The Iron Titan from Tango Tek, but I have been experiencing issues with Iron golems not spawning in water.
Attached are some screenshots of the Farm itself, a golem in the water (Block version) and a before and after golem on land on the same server.
Edit: This should not be seen as a duplicate of
MC-60792 is about golems not able to spawn with blocks next to their head.
Mine is about golems not able to spawn in water. Which was possible in older versions.