The followers of water worship the elemental force of Water.
Water is a True neutral force.
Priests are usually Clerics; many are multiclass Cleric/wizard/Sorceror/DragonDiciple.
Followers can be of any alignment.
Cleric domains: Water, Animal, Death, Destruction, Good, Knowledge, Magic, Plant, Protection, Strength, Travel, Trickery, War
Forbidden Domain: Fire